Epson PX-8 User Manual

EPSON

USER'S

MANUAL

FEDERAL

COMMUNICATIONS

COMMISSION

RADIO FREQUENCY INTERFERENCE

STATEMENT

"This

equipment generates and uses radio frequency energy and

if

not

installed and used properly, that is, in strict accordance with the manufacturer's instructions, may cause interference

to

radio and television reception.

It

has been type tested and found to comply with the limits for a Class B computing device in accordance with the specifications in Subpart

J

of

Part

15

of FCC Rules, which are designed to provide reasonable protection against such interference in a residential installation. However, there

is

no guarantee

that

interference will

not

occur in a particular installation.

If

this equipment does

cause interference to radio

or

television reception, which can be determined

by turning the equipment

off

and on, the user is encouraged

to

try

to

correct

the interference by one

or

more

of

the following measures:

reorient the receiving antenna relocate the computer with respect

to

the receiver move the computer away from the receiver plug the computer into a different outlet so

that

computer and receiver

are on different branch circuits.

If

necessary, the user should consult the dealer

or

an experienced radio/television technician for additional suggestions. The user may find the following booklet prepared by the Federal Communications Commission helpful:

"How

to Identify and Resolve Radio-TV In-

terference

Problems."

This booklet

is

available from the

US

Government Printing Office,

Washington,

D.C.,

20402, Stock No. 004-000-00345-4."

Also, only peripherals (computer

input/output

devices, terminals, printers,

etc.) certified

to

comply with the Class B limits may be attached

to

this

computer. Operation with non-certified peripherals

is

likely

to

result in

interference to radio and TV reception.

USER'S MANUAL

Trademark Acknowledgments

CP/M® is a registered trademark

of

Digital Research™.

1983

by Microsoft

and

Epson) is upward

compatible with the BASIC-80 specifications

of

Microsoft, Inc.

MICROCASSETTE™

is

a trademark

of

OLYMPUS

OPTICAL

CO., LTD. Portable WordStar™

is

a trademark

of

MicroPro International.

NOTICE

•

All

rights

reserved.

Reproduction

of

any

part

of

this

manual

in

any

form

whatsoever

without

EPSON's

express

written

permission

is

forbidden.

•

The

contents

of

this

manual

are

subject

to

change

without

notice.

•

All

efforts

have

been

made

to

ensure

the

accuracy

of

the

contents

of

this

manual.

However,

should

any

errors

be

detected,

EPSON

would

greatly

appreciate

being

in-

formed

of

them.

•

The

above

notwithstanding,

EPSON

can

assume

no

responsibility

for

any

errors

in

this

manual

or

their

consequences.

©

Copyright

1983

by

EPSON CORPORATION.

Nagano,

Japan

TABLE

OF

CONTENTS

Chapter 1 OVERVIEW

..............................................................

1-1

1.1

Unpacking Notes

.........................................................

1-1

1.2 Hardware Configuration

...............................................

1-2

1.3 Software Configuration

................................................

1-10

Chapter 2 STARTING

UP

AND OPERATING

THE

PX-S

..............

2-1

2.1

Starting Up

................................................................

2-1

2.2 Operating the Computer

...............................................

2-11

Chapter 3 OPERATING

THE

COMPUTER UNDER

CP/M

............

3-1

3.1

What

is

CP/M?

..........................................................

3-1

3.2 Files and File Names

....................................................

3-3

3.3 Starting to Use

CP/M

..................................................

3-6

3.4 Using the Keyboard Under

CP/M

..................................

3-10

3.5 Printing When on the

CP/M

Command Line

...................

3-12

3.6 The Concept

of

Logical and Physical Devices

...................

3-13

3.7 The

CP/M

Built-In Commands

......................................

3-16

3.8 Using Utilities and Application Program with

CP/M

.........

3-32

3.9 Communications

.........................................................

3-75

3.10 Other

CP/M

Transient Programs

...................................

3-91

3.11 Finding Out More

About

CP/M

....................................

3-93

Chapter 4

INPUT

AND

OUTPUT

DEVICES AND OPTIONAL

ADDITIONS

TO

THE

PX-S

.........................................

4-1

4.1 Storage

of

Files and Data

.............................................

4-1

4.2 RS-232C Interface

.......................................................

4-22

4.3 Serial Interface

...........................................................

4-29

4.4 Using Printers with the PX-8

.........................................

4-31

4.5 Speaker

.....................................................................

4-34

4.6 Analog Interface

.........................................................

4-36

4.7 Bar Code Reader Interface

............................................

4-37

4.8 The Universal Unit

......................................................

4-38

4.9 System Bus Interface

....................................................

4-39

4.10 Acoustic Coupler

.........................................................

4-42

Chapter 5

THE

SYSTEM INTERFACE

...........................

· ..

····

.. ·· ..

5-1

5.1

The

CP

1M

Configuration

.............................................

5-1

5.2 The IOBYTE

..............................................................

5-2

5.3 The File Control Block (FCB)

................................

········

5-3

5.4 BDOS Function Calls

...................................................

5-4

5.5 Zero Page Locations

....................................................

5-8

5.6 The BIOS Interface

.................................

············

.........

5-9

5.7 The Entry Address

of

the BIOS Subroutines

.....................

5-10

Appendix A PX-8 CONSOLE ESCAPE SEQUENCES Appendix B DRIVE NAME ASSIGNMENTS Appendix C

THE

BATTERIES

Appendix D KEYBOARD LAYOUTS

BY

COUNTRY

Appendix E ASCII CODE TABLE AND INTERNATIONAL

CHARACTER SETS Appendix F MEMORY MAPS Appendix G HARDWARE SPECIFICATIONS Appendix H SOME

EXAMPLE

PROGRAMS

Appendix I

CP

1M

ERRORS AND MESSAGES

Index

Chapter 1 OVERVIEW

II

Chapter 2 STARTING

UP

AND

OPERATING

THE

PX·8

Chapter 3 OPERATING

THE

COMPUTER

UNDER

CPIM

Chapter 4 INPUT

AND

OUTPUT

DEVICES

AND

OPTIONAL

ADDITIONS

TO

THE

PX

8

Chapter 5 THE

SYSTEM

INTERFACE

Appendices

I

•

Chapter 1

OVERVIEW

The PX-S

is

a portable computer which has more facilities

than

many desk

top

computers. This chapter will give you an idea

of

the general capabilities

of

the

computer. The next chapter explain the features

of

the PX-S so that they can

be exploited

to

the full and you as a user can obtain maximum benefit from them in operating the computer. Some features are necessary for running the PX-S normally and would be familiar

to

the user

Who

has handled a microcom-

puter before, but others have been added

to

increase the power

of

the PX-S.

1.1 Unpacking Notes

When you unpack your PX-S package you should find the following items. Confirm that the following are contained in the package. Please keep the packing materials in case the PX-S needs

to

be returned for any reason.

PX-S AC adapter User's Manual (this manual) BASIC Reference Manual Command Summary End-User License Agreement Programmable Function-Key Label

1-1

1.2 Hardware Configuration

This section describes the hardware components

of

the PX-S. All the hardware components required for basic operation are built into a single unit. These include the central processor units (CPUs), memory, keyboard, display, microcassette tape deck and interfaces for a printer and serial communication with other devices including disk drives.

Figures

l.la

to

l.lc

show the appearance

of

the PX-S from several viewpoints.

Fig.

1.1a

1-2

0

] 0

[J

I

CJ

0

I

[I

0

AC

adapter

jack

Fig.

1.1b

Battery

cover

/

0

If

0

IL

0

'--o®.-

CJ

0

z

..

~

CJ

DIP

switch

cover

0

Fig.1.1c

1-3

1.2.1 Configuration diagram

1::

0

0.

U

N

(')

N

en

1:: 1::

1::

II:

0 0

0

;s

0. 0.

0.

U

...J ...J

N N

«

~

(')

ir

N N

II:

en

w w

Cf) Cf)

II:

0 0 0 0

~ ~

~

N

Pi

~

* * * *

1-4

~

p.

~

-;

1-:

-,

I·

1fJ!

I-~

r

r-~

1IfJ)!

t;,

~

r

6!

r-~

:r~

~I

~

--'

el

.~

I

~

~I

c

,

~Ii

N

C, I ?

.....

t;;

L~

.

9'

aL

c;

L.~

,

L~

,-

L.,

~r

rA,

-l-

...

-~

~L.~

..

L.,

;L~

eLi

L

'~

6Y~

~J

1.2.2 The Carrying handle

The handle enables the PX-8

to

be carried easily like a briefcase.

It

is

possible

to

slide the handle up

to

the main body

of

the computer when not in use.

To

extend the handle, place the index finger

of

each hand

on

the serrated por-

tion

of

the handle, and pull it gently towards you,

as

shown in the diagram.

To retract it, simply push the handle towards the computer using even pressure.

Fig.

1.3a

Fig.

1.3b

1-5

1.2.3 The keyboard

The keyboard

is

accessed by removing the protective cover.

To

remove the cover, hold the PX-8 with the keyboard cover towards you and

uppermost, preferably

on

a level working surface.

Fig.

1.4

Place the thumb

of

each hand

on

the

top

of

the cover, with the other fingers

on

each side

of

the cover. Press gently with the index fingers to release the catch

in the

top

centre (see the arrow in the diagram). Now pull the whole cover

towards you using the

both

hands so

that

it slides off.

To

replace the cover, place it centrally over the keyboard, so

that

the edges

of

the cover fit evenly

on

the guides. Push the cover home using the thumbs

applying pressure evenly at

both

ends. Take care

that

the cover moves along

the guides. Do not try to force it vertically down.

If

the cover

is

not in the guides,

take it

off

and try again. Make sure the cover

is

fully up against the LCD screen

and the catch has fitted firmly.

The layout

of

character keys

on

the PX-8 keyboard varies from country to coun-

try. The layouts available are as follows.

ASCII (USA) French German English Italian

Danish Swedish Norwegian Spanish

1-6

It

is

possible

to

change the display to

that

of

any other country

both

by setting

a

DIP

switch and under software control.

In

this manual, the ASCII keyboard

is

used as the standard for explanation.

The PX-8

is

equipped with folding legs which makes

it

possible to change the

keyboard angle. Opening these legs will make the keyboard easier

to

use when

working with the PX-8

on

a table

or

desk.

Fig.

1.5

1-7

1.2.4 Display

The PX-8 uses a large LCD display

of

80 columns x 8 lines,

on

a hinge which

can be folded down

to

protect the display when

not

in use.

Unlock the display by pressing the switch

on

its right toward the rear. When

the display pops

up

slightly, open it by hand.

i.

PUSH

UNLOCK

ITEJI

Fig.

1.6a

The view angle control

on

the front

of

the display makes it possible

to

obtain

the optimum contrast.

EPSON

~~,

,,~

~~~

"'''~

~

',,,

,

" "

I

"

'-",'

I

;

.

.0

20

.

;,

.0

.

.;,

;0

.0

CDI[J

VIEW

ANGLE

PX-8

Fig.

1.6b

1-8

1.2.5 CPU and memory

The PX-8 has three central processor units. The main

CPU

is

a Z80 compatible

microprocessor. This controls the programs which are run

on

the PX-8. A slave

CPU

6301

is

used for display and

Input/Output

(I/O)

control, i.e. communication with other devices such as printers, disk drives, the internal speaker, cassette drives etc. The sub

CPU

7508 controls interfacing with the keyboard and

the Analog/Digital

(A/D)

converter which allows signals from other devices

to

be read as voltages and converted into numbers the PX-8 can understand.

The main

CPU

controls 64K bytes

of

RAM and 32K bytes

of

ROM. The slave

CPU

has

6K

bytes

of

RAM (used as video RAM) and 4K bytes

of

ROM.

All RAM

is

backed

up

by built-in batteries so

that

the contents can be retained

when the power switch

is

turned off.

1.2.6 Microcassette tape deck

The PX-8

is

equipped with a microcassette tape deck which can be used for

saving

data

and program files sequentially. The micro cassette tape deck

is

con-

trolled manually

or

by software.

MICROCASSETTE

L--_----,==;-'-'=="'--.JlJlJUJUlJIJUI..U-"'-"--'

I

=CAPS

18

c5

i""'l

a 0 ["']

['5

0 a

:~:

Fig.

1.7

The maximum number

of

files which can be stored in a microcassette

is

12.

This restriction

is

due to the size

of

the directory

on

the cassette tape.

1-9

1.3 Software Configuration

1.3.1 Operating systems

The operating system

of

the PX-S

is

an extended version

of

CP

1M

which

is

one

of

the most popular operating systems for small business computers and

personal computers.

CP

1M

is

an abbreviation for Control Program for Microprocessors. This operating system was developed by Digital Research and is

a very popular operating system

on

microcomputers because programs deve-

loped under

CP

1M

can be used with minimum modification

on

any computer

using the

CP

1M

operating system. This makes a vast library

of

application pro-

grams for this system instantly available commercially, whereas with a new oper-

ating system they would have

to

be written specifically for the operating system.

EPSON has added a variety

of

useful functions

to

CP

1M

version 2.2 in de-

veloping the PX-S operating system. Further details

of

the use

of

CP

1M

on

the PX-S are given in Chapter

3.

1.3.2 Utilities

The PX-S has the ability to use programs loaded from the built in microcassette tape or from floppy disk (using the optional disk unit),

but

it has a more

powerful facility

to

use programs which reside in ROMs which can be plugged

into the sockets underneath the computer. This

is

a more convenient method

of

storing programs than either tape or disk, since the programs are available

almost immediately, whereas with disk

and

tape it can take a noticeable time

to load them into memory.

• BASIC

The PX-S

is

equipped with a powerful BASIC interpreter which

is

an extended

version

of

Microsoft BASIC which

is

a language widely used for personal com-

puters. Programs can be written by the user and are also available commercial-

ly. There are also listings

of

such programs printed in books and magazines

which can either be typed in and run directly, or will require a minimum

of

modification. Extra commands have been added to cater for the added features

of

the PX-S.

For details

of

BASIC, refer to the BASIC Reference Manual.

1-10

• Portable W ordStar™

The word processor WordStar™

is

one

of

the most popular wordprocessing

programs available

on

microcomputers. Portable WordStar™

is

an enhanced

version

of

the Micropro WordStar™ which been specially modified to take ac-

count

of

the features

of

the PX-S. Whereas the PX-S can be used directly as a wordprocessor with the WordStar ROM installed, the files can be transferred to

other computers using the built in communications

port

of

the PX-S. This means that the PX-S can retain its portability where necessary and another computer used for the main processing.

• Portable Calc™ Apart from use as wordprocessors, the other main impact

on

the business world

made by microcomputers has been in the area

of

electronic spreadsheet pro-

grams. The Portable Calc™ program

is

a ROM based program in this category.

• Portable SchedulerTM

Because

of

the built in clock facility

of

the PX-S, the computer

is

ideal for keep-

ing a diary. The Portable Scheduler™

is

a program which keeps a diary which

not

only allows a record

of

the users appointments to be kept,

but

also enables

the time

to

be signalled using the ALARM function

of

the PX-S.

These utility programs are available as optional ROM capsules.

For

details

of their use refer to the reference manual for each utility program. They represent a small proportion

of

the software available. Please consult your dealer for the

particular application you require.

1-11

Chapter 2

STARTING

UP

AND

OPERATING

THE

PX-8

The first section

of

this chapter describes how

to

set up your PX-8 for the first

time. The remainder

of

the chapter deals with the general functions

of

the

computer.

2.1 Starting Up

2.1.1 Precautions

a) The computer The PX-8

is

a precise machine and in order

to

achieve the best performance,

you should observe the following points:

i) Avoid using or leaving the PX-8 in a place exposed to direct sunlight.

ii) Avoid using or leaving the PX-8 in a

damp

place.

iii)

Avoid using

or

leaving the PX-8 in a place exposed to strong vibration.

iv) Avoid using or leaving the PX-8 in a place exposed

to

high temperatures.

v)

Do not allow the PX-8 to be subjected to shocks

of

any kind.

b) The

AC

adapter

An

AC

adapter

is

provided with the PX-8

to

re-charge the built-in batteries.

When using this AC adapter:

i) Avoid plugging the adapter plug into the AC adapter jack

of

the PX-8

without plugging the adapter to an

AC

outlet.

ii) The shape

of

the power plug differs according

to

the country for which the PX-8 has been shipped. In certain countries there may not be a power plug attached. Your dealer will be able to advise you on the correct plug in this case.

iii)

The PX-8 will take approximately 8 hours

to

charge

if

the PX-8

is

switched

off. However,

if

the power switch

is

ON the time will be greater (at least

11

hours

if

no access

is

made to any device including the keyboard).

2-1

•

iv)

If

you use the PX-8 while charging it

at

the same time, you will

not

be

able

to

use it for as long as you might expect.

If

you intend

to

use the PX-8 from the battery alone, the adapter should be removed from the PX-8 and then reinserted in order to ensure it will fully charge. You should then ensure

that

it

is

left for

at

least 8 hours before use in order to achieve the

maximum length

of

use.

v) The maximum length

of

use

on

battery power

is

15

hours without In-

put/Output

operation.

vi) There are special circuits

to

prevent overcharging

of

the battery.

/I\.

WARNING:

W Never use any

AC

adapter other than that provided.

2.1.2 Before switching

on

Your PX-8 cannot be used immediately after unpacking. The following procedures must be carried

out

before turning

on

the power switch.

Your dealer will probably have carried

out

the procedures in this section when

you receive the computer, in which case you can go

to

section 2.2

to

see how

to

operate the computer.

a) Inserting and charging the battery The PX-8 has been designed as a portable computer powered by rechargeable internal batteries. There are two battery units, main and backup. When the main batteries have insufficient power remaining

to

allow continuous operation, a

message appears

on

the screen for 20 seconds:

CHARGE

BATTERY

then the power

is

automatically turned

off

and the backup

ba~tery

takes over

so

that

the program

or

work in progress

is

retained until the batteries can be

re-charged.

If

the computer

is

not switched

on

the batteries are used to retain

the contents

of

the memory.

It

is

possible, therefore, for the batteries to be-

come discharged.

In

order to prevent this the computer will normally be shipped

with no main batteries. You should therefore proceed as follows:

i) Insert the batteries as described in the addition sheet,

or

as described in

Appendix C.

2-2

ii) Plug the

AC

adaptor

power cable into

an

AC

outlet.

iii)

Plug the

AC

adaptor

output

cable into the PX-8 adaptor jack.

-'"

fFIg.2.1

iv)

About

8 hours (or

11

hours

if

the power switch

is

left on) are required to

fully charge the battery units.

If

when you come to switch

on

the computer

the'

'CHARGE

BATTERY" mes-

sage comes

up

on

the screen, it

is

still possible to use the computer while it

is

charging. IF

NO DISPLAY IS VISIBLE

WHEN

YOU FIRST SWITCH

ON

THE

COM-

PUTER

the batteries may be discharged. This can occur

at

any time. Simply

plug in the charger, wait 10 seconds and then switch

on

again.

IF

NO DISPLAY IS VISIBLE

AT

THIS STAGE, the batteries are so low

that

all the power

is

being used to charge them and there

is

no additional power

available to perform the normal functions

of

the computer. Switch the power

switch off, wait a few minutes and try again.

b)

DIP

Switch settings

As mentioned in Chapter

1,

all

of

the layouts

of

character keys shown in table

2.1 are available with your PX-8 regardless

of

the markings

on

the key tops.

The keyboard layout can be altered by means

of

the

DIP

switch (SW

4)

which

lies under a cover beneath the PX-8 near the keyboard (see fig 2.2).

It

is

also

possible to alter the character set by means

of

software. This

is

described in

Appendix A 'ESC codes' using ESC

"c"

and Chapter 3 under the CONFIG.

Open the

DIP

switch cover underneath the PX-8 (fig 1.1c) and check

that

the

DIP

switch settings correspond to the characters for the country you require,

2-3

as follows:

When you open the

DIP

switch cover you will see a silver flexible flap. Lift

this out

of

the way

and

the

DIP

switch will be seen

on

the left (if the

DIP

switch

cover

is

towards you

as

you are looking

at

the base

of

the PX-8). The

DIP

switch

can then be set. The indivisual switch

is

in the

ON

position when it

is

towards

the side which

is

marked ON.

Only the first four positions

of

the

DIP

switch are used for the character sets. The settings for various keyboard layouts are shown in table 2.1. The switches can be changed with the tip

of

a ball point pen

or

a matchstick.

0 0

0

ROM

2

ROM 1

Fig.

2.2

Table 2.1

Keyboard

DIP

switch position

Layout

1

2

3

4

USA

(ASCII)

ON

French

OFF

ON

German

ON

OFF

ON

English

OFF

ON

Danish

ON

OFF

ON

Swedish

OFF

ON

OFF

ON

Norwegian

OFF

ON

OFF

Spanish

OFF

ON

Italian

ON

OFF

ON

NOTES:

i)

IMPORT

ANT.· Altering the settings will

not

cause any change to occur un-

til

the reset procedure outlined in section 2.2.5

is

carried out.

2-4

'1'

)

ii)

Other

DIP

switch settings are used

for

different purposes. The position

of

switch 5 is used to decide whether a

RAM

check should be carried

out

if

an Intelligent

RAM

disk

is

connected. Switch 6

is

concerned with certain

characters output to the printer when a screen

dump

is carried out. Both

of

these will be explained in Chapter

4.

iii)

Switches 7 and 8 are

not

used. They should be left in the OFF position as

set in the factory.

2.1.3 Initialization

There are a number

of

times when it is necessary

to

reset the system. There

are three different ways

of

resetting the system.

The

action

of

these three reset

modes are summarised in section 2.2.4.

A complete reset (resetting the sub-CPU) and initialisation must be carried out if:

i)

The batteries have been changed

or

inserted for the first time

on

purchasing.

ii) The system has become so corrupt as

to

leave no alternative

but

to

carry

out

a complete reset. This

is

a very rare occurrence

and

there are less dras-

tic ways

of

resetting the computer. The complete reset procedure should

only be attempted as a last resort. See section 2.2.4 for a comparison

of

the different reset situations.

iii) The optional expansion unit has been installed. (e.g. RAM Disk Unit)

a) Resetting the sub-CPU The procedure for resetting the 7508 sub-CPU is as follows:

i)

Turn

off

the power switch.

Fig.

2.3

2-5

ii) Open the plastic switch cover

on

the base

of

the PX-8.

Fig.

2.4

iii) Press the push

button

reset switch near the

DIP

switch. The switch

is

co-

vered to present accidental resetting

of

the sub

CPU.

It

has a hole in the

top through which it

is

possible to push the switch. Do not use a conduc-

tive implement to push the switch,

or

one whose end can break

off

(e.g.

a pencil).

SW4

.~

0 0

1=

€])

0

ROM 2

ROM 1

Fig.

2.5

2-6

iv) Replace the cover.

Turn

the PX-8 over and switch the power back on. The

following message will then be displayed

on

the LCD screen:

SYSTEM

INITIALIZE

ENTER

DATE

TIME (MMDDYYhhmmss)

000000000000

Fig.

2.6

This display image

is

the same as,

that

displayed after system initialization

described in Section 2.2.5b.

The display shows the first

of

a series

of

questions. These set the date and time,

and

the organization

of

the memory.

The first question the display shows allows the date and time

to

be entered.

The expression:

MMDDYYhhmmss

shows the order in which the items have to be entered. The number

of

items

corresponds

to

the row

of

zeroes to the right

of

the message. The first zero

is

covered by a flashing block. This

is

the cursor, which

is

used throughout the

operation

of

the computer to show the position

of

the next character to be print-

ed.

It

can sometimes be moved by using the cursor keys which are the keys

marked with

an

arrow

on

the right

of

the keyboard. This movement

is

under

the control

of

either

an

applications program

or

the overall controlling pro-

gram

or

operating system which

on

the PX-8

is

called

CP

1M.

The use

of

CP

1M

is

discussed in Chapter 3.

In

this particular case only two

of

the cursor keys are active. They are the right and left pointing arrows which allow movement of

the cursor within the bounds

of

the row

of

zeros. By using these keys the

flashing cursor can be placed over

anyone

of

the zeros and when you have chosen a particular position the value can be altered by pressing the appropriate numerical key. The cursor then moves

to

the next position

to

the right.

The various letters correspond to the date and time as follows:

MM: month (e.g.

01

for January and

11

for November)

DD: day

of

the

month

YY: year (e.g.

84

for 1984)

2·7

hh: the

hour

(on a 24-hour clock basis) mm: minutes past the hour ss: seconds past the minute

When these figures have been typed in, any mistake can be corrected by mov-

ing the cursor

to

sit over the incorrect number

and

then retyping

that

number.

The complete values

of

the time and date are

not

entered into the memory

of

the PX-S until the key marked I

RETURN

I

is

pressed. You should check

that

the

values are absolutely correct before pressing the

I

RETURN

I key. Leading zeros

must be added

if

the

month

etc

is

less

than

10. Failing

to

do this will result

in the information being

out

of

sequence.

~

WARNING:

W The date and time

are

not actually updated until the day is input.

It

is possible to update the time and date using either the CONFIG program (see

Chapter

3)

or using the TIME$ and

DATE$

commands in

BASIC

(see

the

BASIC

Reference Manual). These give accurate updating

of

the

time.

When I

RETURN

I

is

pressed, the next question comes

up

on

the screen:

ENTER

DAY (9 to 6)

The cursor

is

flashing over a single zero this time, waiting for a number from

o to 6

to

denote the day

of

the week. The days are represented numerically in

the order:

9 Sunday

1 Monday

2 Tuesday 3 Wednesday 4 Thursday 5 Friday 6 Saturday

The day

is

not

changed in the memory

of

the PX-S until the I

RETURN

I key

is

pressed. The day

is

then stored

and

the next question

is

asked.

The third question

is

ENTER

RAM DISK SIZE

2-8

The PX-S allows

part

of

the memory to be reserved to store programs and data.

It

can be used as

if

it were a disk drive. Since the memory used

is

the standard

Random Access Memory used to

run

programs

and

store working data, the

part

of

memory used as a pseudo-disk drive

is

known as the RAM disk.

In

ac-

cessing the drive under

CP

1M

the drive A:

is

assigned

to

the RAM Disk as

described in Chapter 3. It

is

also possible to have

an

additional block

of

memory

which gives a further 60

or

120 kilobytes

of

storage which plugs into the back

of

the PX-S. Further details are given in Chapter 4.

If

this extra item, the Intel-

ligent RAM disk,

is

attached this particular question will not be asked because

no internal memory can then be allocated for use as a RAM disk.

The cursor lies over the first digit

of

the default value

of

9 kilobytes (9K) ex-

pressed in the form

"09".

Default means the value the PX-S thinks you would

normally expect

to

use, and which it will set unless you change this value.

Up

to

24K

of

RAM can be reserved for the RAM disk.

SYSTEM

INITIALIZE

ENTER

DATE

TIME

(MMDDYYhhmmss)

000000000000

ENTER

DAY

(0

to

6)

0

ENTER

RAM

DISK

SIZE

09

Fig.

2.7

The procedure for entering the size

of

RAM disk you require

is

the same as

with the previous questions. Since the value entered

is

that

displayed, simply

press the

I

RETURN

I key

if

you wish to use the default value

of

9K

bytes.

If

you

wish

to

chan~e

the size

of

the RAM disk, alter the value

and

press the I

RETURN

I

key. The RAM disk size can only be set in

lK

byte units and the value 0 and

2 to 20 can be input.

When the RAM disk size has been set the next question is:

ENTER

USER BIOS SIZE 99

This

is

a facility for advanced programmers. The cursor will be positioned over

the first digit

of

a pair

of

zeros. Unless you have a specific need to use the USER

BIOS area simply press the

I

RETURN

I key

at

this stage.

The use

of

the USER BIOS

area

is covered in the OS Reference Manual. The

location

of

the USER BIOS

area

can be seen in the memory map (Appendix

F). The number entered in response

to

this question denotes the number

of

256

2-9

256 byte blocks. Note

that

if

USER BIOS area is reserved, the

total

area

of

the USER BIOS plus the RAM disk

cannot

exceed 24K bytes.

If

U is

the

num-

ber entered for the USER BIOS and R

is

the number entered for the

RAM

disk,

then

U/4

+ R must

not

exceed 24. This is because the

RAM

disk is assigned

in units

of

lK

and

the USER BIOS in units

of

114 K.

Before the USER BIOS question has been answered the display will show

SYSTEM

INITIALIZE

ENTER

DATE

TIME

(MMDDYYhhmmss)

000000000000

ENTER

DAY

(0

to

6)

0

ENTER

RAM

DISK

SIZE

09

ENTER

USER

BIOS

SIZE

00

Fig.

2.8

On

pressing the I

RETURN

I key it will clear

and

ask a further question.

RAM

DISK

FORMAT

(YIN)

?

Formatting a disk makes it possible for programs

and

data

files

to

be stored

as

if

the

RAM

disk were a conventional floppy disk. Until it is formatted

data

cannot be written

to

the disk. There are times when it

is

necessary

to

go through

the initialization procedure when the disk contains files.

In

this case only is it

permissible

to

say

'N'

to

this question. The disk will

not

be formatted,

but

there

is no guarantee

that

the files will be intact

or

that

the RAM disk can be read.

When the Y key is pressed, the

RAM

disk will be formatted

and

the display

will change

to

show the

MENU

screen.

A typical

MENU

screen would be:

***

MENU

screen

***

03/01/84

(WED)

04.26.07

54.5k

CP/M

C:PIP C:PIP

COM

C:STAT

COM

C.SUBMIT

COM

C:FILINK

COM

C.TERM

COM

C.CONFIG

COM

Fig.

2.9

ver

2.2

PAGE

1/1

C.XSUB

COM

B.BASIC

COM

This type

of

screen makes it easier

to

run

programs

and

saves typing. The set-

ting up

and

use

of

the

MENU

screen

is

described in section 2.2.3d.

2-10

2.2 Operating The Computer

2.2.1 The Keyboard

If

you are used

to

using a normal typewriter

or

another computer, you will see

that

the keyboard is similar. You will already have used the keyboard

if

you

have set

up

and

initialized the PX-8,

but

in order

to

use all

of

its facilities you

will need

to

study this section

to

understand the special keys

and

key combina-

tions. There are also special key combinations which only apply

if

you are us-

ing

CP

1M,

the BASIC language

or

a particular applications program. Special

use

of

certain keys

and

key combinations under

CP

1M

are explained in Chapter 3, and under BASIC in the BASIC Reference Manual. Consult the appropriate Manual for any applications software.

a) Alphanumeric keys Most keys

on

the keyboard generate characters, alphabetic, punctuation and

numerals

or

graphics characters. These keys are called auto-repeat keys. Each

auto-repeat key generates a certain character code repeatedly

if

it

is

pressed and

held

on

for more

than

a specified period

of

time. This normally causes a charac-

ter

to

be printed

on

the screen. Some keys are switch keys which alter the charac-

ter code

output

by

the character keys, for example

to

allow one key

to

output

either upper

or

lower case characters. Other keys are special keys which allow

insertion

and

deletion

of

characters, for example.

D

:.

Auto-repeat keys

_ :

Switch

keys

Fig.

2.10

The time before starting repetition

and

the repetition interval can be set by the

2-11

user by means

of

an

ESC code sequence. See Appendix B.

If

you are not familiar with a computer with auto repeat keys, you may hold

them down

too

long initially, although you will soon adjust to the response

time.

If

the key

is

held down past the repetition time, the character

will

be printed

more

than

once and this could cause a program

to

respond in a way you might

not

expect.

For

example the System Display uses the I ESC I key

to

move back

through the various levels, and also as the exit key.

If

you hold down the key

for too long it

is

possible to exit when you did not mean to.

Sometimes a key may

not

appear to respond. This

is

because a program

is

processing data. Do not press the key again as the key you have pressed

is

stored

in a buffer and will be retrieved when the program

is

ready to use your input.

Continued pressing

of

a key may cause action to occur which you did not intend.

b)

Switch keys

Switch keys allow the other keys to perform more

than

one function.

For

example, they can allow upper and lower case (capital and small letters)

to be obtained from the alphabet keys.

I SHIFT I : Pressing this key together with a key other than a switch

ls:ey

enters

the alternative code assigned to that key. The

I SHIFT I key should be held down

before the other key

is

pressed. Thus if any numerical key

is

pressed whilst hold-

ing the

I SHIFT I key down the alternative character above the numeral

on

that

key will be printed. The

I SHIFT I key also allows upper and lower case letters

to be obtained from the alphabetical keys.

I

~t~

I : Pressing this key makes the alphabet keys enter upper case letters

without pressing the

I SHIFT I key. The lock

is

removed by pressing the key

again. When the I

~t~

I

is

set the LED marked

"CAPS"

at the top

o~

the key-

board

will be lit.

If

the I SHIFT I key

is

pressed when the Caps Lock IS set, the

lower case character

is

printed instead.

I CTRL I : There are two I CTRL I keys, one to the left

of

the keyboard above

the

I SHIFT I key,

and

one to the right

of

the space bar. They are equivalent.

Pressing either key makes it possible to enter control codes from the keyboard. Control codes are characters which are not printed. Some correspond to characters such as a carriage return, line feed, etc., others are used by applications

software packages to perform such functions as clearing the screen

or

going

to the end

of

the text. Control codes are normally associated with alphabetic

keys and are indicated by the word

"Control"

followed by the associated let-

ter, for example,

"Control

C".

This

is

often abbreviated with the

"CTRL"

2·12

joined to the letter by a hyphen.

For

example pressing the I CTRL I and the

(g

key

at

the same time could be written I CTRL

1-

(g

. Another common way to

show a control character is to place a

,,""

character in front

of

the letter. Thus

I CTRL 1 -

(g

could also be written as

""C"

. This will be printed

on

the screen

if

a control character is entered

on

the command line in

CP

1M.

To obtain a

control character the

1 CTRL 1 key should be held down and then the alphabetic

character pressed.

I

G~~~H

I : This key has two functions. Pressing a character key together with

this key enters the graphic character code assigned

to

the key.

Not

all keys have

graphics characters assigned to them.

It

is

also possible to have user defined

characters. Those are defined

in

the codes indicated in ( ).

Fig.2.11a

ASCII keyboard

If

the

IG~'i~1

key

is

pressed while the I SHIFT I key

is

held down, a block

of

keys can be used as a numeric key pad. The key layout

is

as follows:

Fig.2.11b

ASCII keyboard

2·13

When the PX-S

is

in the numeric keypad mode the LED at the top

of

the key-

board marked

"NUM"

will be lit. Pressing this key together with the

1

SHIFT

1 key when the PX-S

is

in this mode returns to the normal state.

c) Special keys

There are a number

of

special keys some

of

which allow control

of

the cursor

and also simplify operation

of

the PX-S. Some

of

them also allow interruption

of

the computer so that, for example, the screen can be dumped

to

a printer.

The CURSOR KEYS are the keys marked with arrows on the right

of

the key-

board. They are used to move the cursor

on

the screen under control

of

the applications program. As was seen in the initialization, they may not all be active at once and may only allow movement within certain limits. The cursor keys are not supported by

CP/M.

1

RETURN

I:

This means carriage return, and

is

normally used to place the cur-

sor at the beginning

of

a line. Since this would place the cursor

on

top

of

the characters already printed, a line feed

is

normally added to a carriage return

by the software. The

1

RETURN

1 key

is

also used

to

signal the end

of

entry when

a sequence

of

characters are being entered into the computer, otherwise the soft-

ware has no way

of

knowing when the user has finished. Until the carriage return

character

is

entered, the software will wait for the next character, unless a sin-

gle

character entry

is

required. The ASCII code for a carriage return

is

13

decimal

(OD

hexadecimal), which corresponds to a 1

CTRL

1-

IMl

.

1

STOP

I:

In

CP/M

pressing this key clears the keyboard buffer and makes

a warm start

of

the system. In BASIC it

is

used

to

stop a program.

1

CTRL

1 and 1

STOP

I:

Pressing these keys simultaneously immediately terminates

I/O

operation, and makes a warm start

of

the system.

1

ESC

I:

Pressing this key enters

an

ESCAPE code (ASCII code

27

decimal).

It

is

used frequently

to

exit from many

of

the special function programs

of

the

PX-S.

1

PAUSE

1 : Pressing this key enters a PAUSE code (ASCII code

19

decimal) which

can be used

to

stop printing to the screen. For example

if

there are too many

files

on

a disk

to

be displayed on the screen

at

one time pressing thel

CTRL

Ikey

can temporarily stop the printing

of

the filenames. The effect

of

a pause can

be reversed by pressing any other key.

2-14

1

CTRL

1 and 1

ESC

1 or 1

PAUSE

1 : Pressing the 1

CTRL

1 and 1

ESC

1

or

[PAUSE]

keys calls

a subroutine specified.

1

HELP

I:

Pressing this key enters al

HELP

Icode (ASCII code 0). This is some-

times used in applications software

to

show a table

of

commands etc. On the

PX-S the main use

of

the key is in combination with the 1

CTRL

1 key

to

enter

the System Display.

1

CTRL

1 and 1

HELP

I:

Pressing these keys simultaneously turns

on

the System

Display. This

is

described in full in section 2.2.2.a.

1

TAB

I:

This

is

a key which moves the cursor

to

pre-set positions across the

screen. These are normally in steps

of

S characters. When the TAB key

is

pressed

it generates an ASCII code 9.

~:

Pressing this key enters

a~character

(ASCII code

127

decimal).

It

is

usually used to delete the character under the cursor. However, some ap-

plication programs use it in different ways.

It

has a special use on the

CP/M

command line and this will be explained in Chapter 3.

1

CLR

I:

This

is

obtained by

USi,g

the

IL~

key with

the[QKJkey.

Both

keys must be pressed even

if

the

~~~

key

is

active.

It

enters a -

which has the ASCII code

12

decimal.

If

used in

an

applications program it

normally clears the screen.

1

INS

I:

Pressing this key enters

an

ASCII code

IS

decimal. Normally this

is

used

to

allow characters

to

be inserted. Its use

on

the

CP/M

command line

is

described in Chapter 3, as it has a different function.

1

SCRN

I:

This key

is

used

to

change the cursor tracking mode. The PX-S displays a window on a virtual screen. The cursor moves over the virtual screen. Normally the window follows the cursor. This

is

called tracking mode. The

key (obtained by pressing the

1

INS

1 and 1

SHIFT

1 key)

is

used to turn the track-

ing mode on and off.

If

thel

SCRN

Ikey

is

pressed while the PX-S

is

in tracking

mode, the window will be frozen over a particular portion

of

the virtual screen.

This

is

known as the non-tracking.mode. Pressing thel

SCRN

Ikey

when the PX-S

is

in this mode will turn the tracking mode

on

again and move the window

on

the virtual screen so that the cursor

is

displayed in the window.

rID:

This key causes the cursor to Back -Space and delete the last charac-

ter. It enters a BACKSPACE character (ASCII code

S).

In

some applications

2-15

software, and

on

the CP

1M

command line, it

is

the only way

to

delete a

character.

I

HOME

I:

The L!,!OME I key

as

the name suggests moves the cursor

to

the top

left hand corner

of

the virtual screen (not the window).

KEYS

~

TO I PF5 I : The Programmable Function keys

These are a set

of

keys which enable the user

to

enter a string

of

characters

which will be printed when the key

is

pressed. This

is

as

if

they had been typed

in by the user

at

the keyboard. The PX-8 is programmed with a default set

of

characters which allow the most common

CP

1M

commands to be input with

one keystroke. Also when BASIC

is

entered, a default set

is

available, which

corresponds to the common BASIC commands.

The strings are altered by means

of

the CONFIG program in

CP

1M, which

is

described in Chapter

3.

The BASIC Reference Manual describes how

to

alter

them in BASIC.

Pressing a programmable function key together with the

I

SHIFT

I key enters

a different user defined string. The names PF6

to

PFIO are given

to

the shifted

keys

I

PF1

I

to

I PF5 I , i.e. a value

of

5 is added

to

the number

of

the program-

mable function key

if

it

is

shifted.

Since there are ten function key strings

it

is

sometimes difficult

to

remember

which key has which string associated with it. The strings assigned

to

each func-

tion key can be displayed

on

the eighth line

of

the screen.

If

the eighth line

shows the following display:

dir

Idump

type

Isubmit

stat

Iddt

pip

Iterm~

config~/filink~

Fig.

2.12

This means function key lliIJ will print the characters

"dir"

when pressed,

and

"dump"

when pressed with the shift held down (i.e. the I PF6 I key

is

pressed)

and so

on

across the screen. The "

.J

"character

means that the equivalent

of

pressing the I

RETURN

I key

is

also added

to

the characters printed. A I

RETURN

I

is

not added with the characters

if

it

is

likely that other commands

or

parameters

2-16

need to be added.

The assignments can be changed using the CONFIG program described in Chapter

3.

This also has

an

option

to

switch the display

of

these function key assign-

ments on and off.

Pressing a programmable function key (

LfITJ

to I PF4 I ) together with the

I CTRL I key calls a subroutine specified by the user.

If

no subroutine

is

speci-

fied, nothing happens.

Pressing the

I CTRL I and I PF5 I keys simultaneously outputs, the contents

of

the

display screen to the printer.

2-17

2.2.2 Switching the PX-8

on

and

off

The PX-S has a power switch

on

the right hand side (see fig 2.3) which

is

the

normal way the computer

is

switched

on

and

off

at

the beginning and end

of

a session

of

using the PX-S. However, the PX-S

is

not switched

off

completely

as a mains operated computer would be

if

the power was turned off. The pow-

er switch can be thought

of

as a means

of

temporarily halting the operation

of

the computer, so that the batteries are conserved. As soon as the power

is

turned

on

again it

is

possible

to

begin exactly where you left off, even

if

you

were in the middle

of

typing a word

or

running a program.

The power switch

is

not the only means by which the power can be switched

on

and off. The power switch

of

the PX-S

is

controlled by the computer, and

can and

is

switched

off

under software control. Thus,

if

it

is

not used for a

length

of

time (which can be set by the user using the CONFIG program

described in Chapter 3), it will switch itself

off

to

conserve power. The user

can also program the computer

to

switch itself

off

at

specific times. Furthermore the PX-S can switch itself on, run a particular program and then switch itself

on

again

to

run the same

or

another program. This ability

to

switch itself

on

and

off

is

a powerful feature

of

the computer.

To

switch the power

on

when the switch is already in the

on

position, switch

it

off

and on again. This means, holding the computer with the keyboard nearest

to

you, moving the switch towards you and then away from you again.

To switch the computer

off

when it is already in the

off

position, switch the

power switch

to

the

on

postion and then

off

again.

Because the computer can switch itself

on

and off, the power switch position

may not reflect the true state

of

the power.

For

example

if

the PX-S switches

itself off, the power switch will still be in the

on

position, even

th~ugh

t~e

po~

er

is

off. Similarly,

if

the PX-S switches itself on, the power

sWItch

wIll

be m

the

off

position even though the power

is

on. Holding the PX-S normally with

the keyboard towards you, the power switch

is

on

the right hand side

of

the

computer. The ON position

is

towards the back

of

the computer. The OFF po-

sition

is

towards the front

of

the computer.

2-18

There are also two

ways

to switch the power off: the restart and continue modes.

The selected mode

is

determined by the conditions prevailing at the time the

power

is

turned off. When the power

is

switched

off

in the restart mode, the

Menu or CP

1M

command line display

will

be activated when the power

is

turned

on

again. When the power

is

switched

off

in the continue mode, the operation

which

is

being executed when the power

is

turned

off

will be continued when

the power

is

turned on again.

i)

Conditions under which the restart mode

is

selected:

- When the power switch

is

turned off.

- When system initialization

is

performed.

- When the sub-CPU is reset.

- When the BIOS POWEROFF r:outine

is

called. (See Chapter

5)

ii) Conditions under which the continue mode

is

selected:

- When the power switch

is

turned

off

while pressing the I CTRl I key.

- When the auto power

off

time

is

reached, because no key has been

pressed. (See Chapter 3.)

- When the main battery voltage drops below a certain level (power failure).

- When the BIOS POWEROFF routine

is

called.(See Chapter

5)

2-19

SWITCHING

THE

PX-8 ON

As can be seen from the above explanation, when the PX-8

is

switched on, a

number

of

routes can be taken by the operating system.

If

the power was

switched

off

in the continue mode, operation will continue

at

the point at which

it was switched off.

If

the PX-8 was simply switched

off

in the restart mode,

there are a number

of

options possible. These also vary with the way the com-

puter

is

switched

on

(Le. manually

or

under the control

of

the PX-8).

In

order

to understand these possible situations,

an

overview

of

the operating system

is

necessary. However,

to

keep the information together for reference, the fol-

lowing summary

of

what can happen when the PX-8

is

switched

on

is

given

at this point, even though some

of

the concepts have not been covered

at

this

stage in the Manual.

i)

If

the Password has been set the PX-8 will ask for the Password

to

be

en~

teredo

It

will not be possible

to

operate the system any further without en-

tering the correct Password.

ii)

If

the PX-8 has been switched

off

in the continue mode, the program which was being used, will continue at the point it had reached when the PX-8 was

switched off. Thus if the program was waiting for input, or

was

process-

ing information, this would continue.

iii)

If

the PX-8 was switched

off

in the restart mode, either the MENU page

or the

CP/M

command line would be displayed.

iv)

If

BASIC was in use when the PX-8 was switched off, it

is

possible

to

re-

enter BASIC.

If

the MENU

is

switched on, this

is

done simply by pressing

the

I

RETURN

I key.

If

the MENU

is

switched off, it would appear not

to

be present.

It

can be retrieved (see the SAVE command in Chapter 3), but

you may not remember that you were using BASIC.

It

is

wise to set the

MENU

on

before switching

off

when using BASIC, so that it

is

evident

that BASIC was in use, and

to

prevent any loss

of

programs stored in the

five program areas.

IF YOU SWITCH

THE

COMPUTER ON AND NO DISPLAY APPEARS:

First check that the view angle

of

the LCD

is

set so that you can

see

the screen

display.

If

there

is

still no display, the battery needs recharging. Plug in the AC charg-

er, wait a few seconds and then switch

on

again.

2-20

2.2.3 The PX-8 operating system modules

The operating system

of

the PX-8

is

functionally divided into several units which

are referred to

as

modules. Some

of

them are part

of

the

CP/M

operating sys-

tem and others supplement it.

i) System Display module

This module enables the microcassette tape

to

be operated manually and

also

to

check and reset some

of

the system parameters. This module can

normally be operated while applications software

is

running. Many

of

the following modules have parameters which can be changed by using this module.

ii) Password module

This module makes it possible

to

stop unauthorised users from using the

PX-8 without knowing an entry password.

iii) MENU module

This module displays program files and data files

on

the screen and makes

it easier for the user

to

run any program file by selecting it

on

the screen,

using the cursor keys rather than having it to type the full name.

iv) Screen dump module

This module

is

used

to

make a copy

of

the current screen

on

a printer.

v)

Console Command Processor (CCP) This

is

the part

of

the

CP/M

operating system which interprets command

strings typed

on

the keyboard. This module includes the

CP/M

built-in

commands (DIR, TYPE, REN, ERA, SAVE and USER).

vi) Basic Disk Operating System (BDOS)

This

is

the part

of

the

CP/M

operating system which manages disk files.

It

also treats the ROM capsule and RAM as disk devices.

vii) Microcassette Tape Operating System (MTOS)

This module manages microcassette tape files.

viii) Basic

Input/Output

System (BIOS)

This part

of

CP/M

which acts as the interface between the operating sys-

tem and

input/output

devices e.g. the screen, keyboard and RS232 in-

terface.

ix) Microcassette

Input/Output

System (MIOS)

110

interface between MTOS and microcassette firmware

x)

Clock module This module controls the alarm and wake functions and updates any time displays.

xi) System activator

This module controls system activation, deactivation, the auto-start function and initialization.

2-21

The best way

to

understand the operation

of

the modules which are directly

under the control

of

the user is

to

check

and

alter the status

of

the parameters

involved using the System Display module.

a) System Display module The System Display

is

brought

on

to

the screen

by

pressing the I

CTRL

I

and

I

HELP

I

key simultaneously. The screen is

then

changed

to

show a display similar

to

one

of

the following:

***

SYSTEM

DISPLAY ***

03/01/84

(THU)

12:01:34

<MENU>

<RAM

DISK>

009

kb

<AUTO

START>

<USER

BIOS>

000

256 b <MCT

MODE>

stop,

nonverify

<COUNT>

65535

<MENU

DRIVE>

CBA

<MENU

FILE> 1 .COM

2 3 • 4 •

-

Select

number

or

ESC

to

exit.

l=password

2=alarm/wake

3=auto

start

4=menu

5=MCT

«-

I

<-

Imount

Ilf/dirinit

-»

lerase

0001

***

SYSTEM

DISPLAY

***

<RAM

DISK)

009

\<b

<USER

BIOS>

000

256

b

<MENU

DRIVE>

CBA

Fig.

2.13a

03/01/84

(THU)

12:01:34

<AUTO

START)

(MCT

MODE)

stop,

nonverify

<COUNT)

65535

<MENU

FILE> 1 .COM

2.

3 • 4

-

Sel

act

number

or

ESC

to

e>:

it.

l=password

2=alarm/wake

3=auto

start

4=menu

5=MCT

«-

I <-

Imount

'

./dirinit

-»

lerase

0001

Fig.

2.13b

This screen image is referred

to

as the System Display.

It

shows a

number

of

items

of

information which would be

hard

to

determine except

by

running a

separate program

to

interrogate the system. Since the System Display can be

obtained even in the middle

of

an

applications program it is a fundamental

part

of

the PX-8 which you will be using regularly, so

try

altering as many

of

the

parameters as possible

to

see what they do.

Looking

around

the screen you will see the following:

The

first line shows the title "SYSTEM

DISPLAY"

in the

top

left

hand

corn-

er. Followed

by

the date

and

time.

It

may show one

or

other

of

the words

"<MENU>"

and

"<PASSWORD>".

Figs 2.13 a

and

b show cases with

and

without these options displayed. These are visible

if

the corresponding op-

tions have been set.

The second line shows the

ALARM

or

WAKE time together with the appropri-

ate string.

If

this option has

not

been specified, the line will be blank.

2-22

The third line shows the size

of

the

RAM

disk as set

on

initialization

or

using

the

CONFIG

program (see Chapter 3). Next

to

it

will be

an

Autostart string

if

one has been specified. The title

"'<AUTO

START>"

will still be present

even

if

there is

no

string specified.

The

fourth line shows the size

of

the USER BIOS, in 256 byte pages as set

by

initialization

or

the

CONFIG

program.

To

the right

of

the

line are a series

of

parameters associated with the Microcassette drive.

The

fifth line is concerned with the MENU.

The

drives from which the files

will be taken are displayed next

to

the" < MENU

DRIVE>

" title

on

the left.

The

right

hand

side

of

the line shows which file extensions are

to

be chosen

for display

on

the

MENU.

The

sixth line shows the

prompt

string

and

flashing

prompt

to

enable one

of

the

options

on

the seventh line

to

be taken'.

The eighth line shows

the

strings associated with

the

programmable function

keys which are used

to

control the Microcassette drive.

If

a cassette has been

mounted, only the

I

PF6

I (shifted I

PF1

I ) key will be active.

The following items

CANNOT

be changed

by

using the System Display:

1)

Month/Day/Year

(Day

of

week)

2) Hour: Minute: Second

3)

RAM

disk size

4) Size

of

USER BIOS area

(1st line) (1st line) (3rd line) (4th line)

They are changed either by the initialization procedure,

or

the

CONFIG

pro-

gram described in Chapter 3.

The following sections explore the use

of

each

of

the

modules which can be

changed

by

using the System Display.

NOTE:

System Display cannot be entered during

PASSWARD

or

ALARM/WAKE

display.

2-23

b) Password module The Password module makes it possible

to

prevent the computer system from

being used by unauthorised people.

It

should be used with care.

It

is

not

possi-

ble for the Password

to

be determined once it has been assigned.

If

the Pass-

word

is

being used, make sure

that

all

data

and

programs including those in

the RAM disk are saved

to

disk

or

Microcassette tape before switching off.

If

it

is

necessary to break the Password, all

data

and

programs will be lost.

From the System Display press the [j]key and lines 6 and 7 will change to:

***

SYSTEM

DISPLAY

***

<RAM

DISK>

009

kb

<USER

9105>

000

2~6

b

<MENU

DRIVE>

C9A

03/01/84

(THU)

12:01:34

<AUTO

START>

<MCT

MODE>

stop,

nonverify

<COUNT>

65~3~

<MENU

FILE> 1 .COM

2.

3 • 4 •

-

Select

number

or

ESC

to

return.

l=off

2=assign

Fig.

2.14

i) Setting a password

To assign a password, press

the~

key and the prompt will change to:

***

SYSTEM

DISPLAY ***

<RAM

DISK>

009

kb

<USER

9105>

000

256

b

<MENU

DRIVE>

C9A

03/01/84

(THU)

12:01:34

<AUTO

START>

<MCT

MODE>

stop,

nonverify

<COUNT>

65~3~

<MENU

FILE> 1 .COM

2.

3 • 4 •

-

Input

password,

ESC

to

cancel.

Fig.

2.15

with the cursor

on

the seventh line awaiting the password. Type in your pass-

word (this

is

limited to 8 characters) and press the I

RETURN

I key when you have

typed in all the characters. Remember the password you have typed because there

is

no way

to

find out what it

is

once you have pressed I

RETURN

I .

The System Display screen will show the

word" < PASSWORD>

" in the

top

right hand corner as soon as the I

RETURN

I key

is

pressed after the password

has been entered.

Having entered a password, switch

off

the PX-8, wait a

few

seconds and switch

it

on

again. The screen will now show:

2-24

PASSWORD

Fig.

2.16

The system cannot be used unless the correct password

is

typed from the key-

board. Type the password and press the

I

RETURN

I key. The letters you type will

not

be displayed

on

the screen.

If

the typed word

is

incorrect, the cursor will

be returned to the starting position. When the correct word

is

entered, the speak-

er will beep

and

the display will change

to

either the MENU page

or

the

CP

1M

command line display.

ii)

Removing the

PASSWORD

Press the I

CTRL

I and I

HELP

I keys to go back to the System Display again. This

time after pressing

1,

remove the password by pressing 1 again.

If

you had

pressed 1

to

change the password status and then decided not to do so, the

I

ESC

I key could be used

to

return

to

the options choice line. In general, press-

ing

I

ESC

I anywhere in the System Display will successively take you back a

level, so that you eventually leave it altogether.

The user will be asked

to

supply the password under the following conditions,

not

just when the PX-8 is switched on:

a)

If

power

is

turned

on

by the power switch

or

the wake time

is

reached with

the password mode specified.

b)

If

the alarm

or

wake mode

is

activated while the password

is

still being en-

tered, both will be treated as an alarm string.

NOTE:

The P X-8 will only treat the wake string as

if

it

were an alarm string

if

the Pass-

word

is

activated. The user will then be asked

for

the password again after press-

ing

I

ESC

I to exit

from

the alarm/wake message.

c) Pressing the reset button will return the user to the password screen.

The password mode

is

terminated in one

of

the following cases:

2-25

a) When the password

is

typed correctly.

b) When power

is

turned off.

c) When the auto shut-off time

is

reached.

d) When power failure

is

detected.

The password mode

is

interrupted when the alarm/wake time

is

reached.

WARNING: The only way to exit

from

the password

if

it is

not

known is

to

initialize

the system

by

either pressing the reset button with the right-hand I

SHIFT

I

and

Ilt~~~HI

keys held down or

by

doing

afull

system reset, as when start-

ing the up the system

for

the first time.

In this case all

your

programs will be lost

and

also anything stored in the

RAM

disk area.

2-26

c) Clock module - the

ALARM

and WAKE functions

The clock module manages the software clock

and

controls the ALARM and

WAKE functions which allow the PX-8

to

switch

on

and

present a message

or

start a program running.

If

the computer

is

in use, and alarm

or

wake time

is

reached, the program being

run

will be interrupted. The screen will clear and

show the message.

In

order to familiarise yourself with the possible ways

of

setting and using the

ALARM and WAKE functions press I

CTRL

I and I

HELP

Ito

turn

on

the System

Display and then press option 2

to

change the ALARM and WAKE options.

Lines 6 and 7

of

the screen then change to:

***

SYSTEM

DISPLAY ***

03/01/84

(THU)

12:01:34

<MENU>

<AUTO

START>

<RAM

DISK>

009

kb

<USER

BIOS>

000

256

b

<MENU

DRIVE>

CBA

<MCT

MODE>

stop,

nonve~ify

<COUNT>

65535

<MENU

FILE) 1 .COM

2.

3 • 4 •

-

Select

numbe~

o~

ESC

to

~etu~n.

l=off

2=ala~m

3=wake

4=message/st~ing

Fig.

2.17

It

is

not possible

to

have

both

the ALARM

and

WAKE functions operating

together.

If

option 2

is

taken it will cancel any WAKE setting and replace it

with

an

ALARM. Option 1 switches

off

whichever

of

the ALARM and WAKE

has been set, and the message string (option

4)

is

used with both the ALARM

and WAKE functions in a slightly different way.

i)

SETTING

THE

ALARM

Before looking at the various options for setting the ALARM, the following example shows how to set the ALARM simply to switch

on

the computer and

display a message

at

a specific time and date.

Press the

~

key and the

prompt

changes as follows.

***

SYSTEM

DISPLAY

***

<RAM

DISK>

009

kb

<USER

BIOS>

000

256

b

<MENU

DRIVE>

CBA

03/01/84

(T~U)

12:01:34

<MENU>

<AUTO

START)

<MCT

MODE>

stop,

nonve~ify

<COUNT>

65535

<MENU

FILE> 1 .COM

2.

3 • 4 •

-

Set

ala~m

time,

ESC

to

cancel.

MMDDhhmm

Fig.

2.18

2-27

The cursor

is

to the right

of

the prompt string. The PX-8 now expects you to

type in the time

at

which you wish the alarm to sound. The prompt shows the

order in which the date and time should be entered:

M: Month D: Day h:

Hour

m: Minute

Care should be taken to ensure that a leading zero

is

added to a single digit value.

In order to have the alarm sound within a reasonable time, so that more examples can be tried, set the date to that shown

on

the top line

of

the System Dis-

play, and the time to two minutes later. As

an

example

if

the date and time

shows

"01/18/84

(WED) 11:38:45" enter "01181140" for the ALARM time.

This ensures that the alarm will sound

at

"11:40"

on

the same day. When you

reach the last character, the cursor will flash over this character,

to

show you that you are in the last position; otherwise the cursor will move to the next position.

If

you decide you do not want

to

enter a value, simply press the I ESC I

key.

If

one or more

of

the characters are wrong, you can move back and forth

along the line using the cursor keys. When you press the

I

RETURN

I key, the

ALARM time will be entered onto the second line

of

the System Display.

The label

"<

ALARM

MSG>

" will appear

to

the right

of

the alarm time, but

the rest

of

the line will be blank until a message string

is

inserted. As you have

been returned

to

the prompt line shown in fig 2.17, press the

[1]

key so that

a message string can be inserted. Write a message

of

up to

40

characters, for

example "Time to telephone home". When the

I

RETURN

I key

is

pressed the mes-

sage string will be entered next to the

"<

ALARM

MSG>"

label.

When the alarm time

is

reached the speaker will sound a warbling note and

the screen will clear

to

show the display

of

fig 2.19.

<ALARM

TIME)

03/01

06:00

(ALARM

MSG)

good

morning

Press

ESC

key

Fig.

2.19

2-28

If

no message string was entered, the rest

of

the line after the

"<

ALARM

MSG>"

label will be blank.

You can return to whatever was happening when the alarm sounded by pressing the

I ESC I key. The alarm might also have occurred when the PX-8

was switched off. In this case the speaker would sound in exactly the same way and the power switched

on

to

display the same screen. As this can happen when

you might not be near the computer and the battery could be discharged, the

auto power

off

time will decide when to switch the power

off

(see section 2.2.2

and the CONFIG program

of

Ch~pter

3....()r

details

of

how to set this).

The PX-8 will exit from the ALARM screen when:

• The

I ESC I key

is

pressed.

• Fifty seconds has passed.

• The power switch

is

turned off.

• The battery needs recharging.

Unless the power

is

switched

off

the PX-8 will revert

to

the state it was in im-

mediately before the alarm was sounded.

ii)

Ways

of

setting the

ALARM

The example above showed how to set the alarm

to

go

off

at a specific time

on

a specific day. There are a number

of

ways that the alarm can be set, for

example to repeat

at

specific intervals. This involves the use

of

wildcards. When

an

ALARM date and time

is

input, the PX-8 compares the current date and

time with the string

of

characters input character by character.

By

using an aster-

isk

or

question mark as a wildcard in the ALARM string, the comparison will regard the position where the wildcard character was inserted as always matching.

For

example, type

"*

* * * 0930" into the string following the

"MMDDhhmm"

prompt when taking the ALARM option. This will change

the alarm time following

the"

< ALARM

TIME>

" label to " * * / * * 09:30".

It

will cause the alarm

to

sound every day

at

9.30 am. The wildcard option

is

not completely flexible.

It

can only set the alarm

to

go

off

at

intervals

of

one

minute, ten minutes, one hour, twenty four hours and monthly.

It

is

also pos-

sible to set the ALARM

to

go

off

at

specific intervals in a given period e.g.

every ten minutes for an hour. The following table

is

a summary

of

how to

use the wildcard.

2-29

TYPE

IN

DISPLAY READS

NOTES

Every minute:

********

*

*1*

*

*:

* *

sounds every minute

Every

10

minutes:

*******5

*

*1*

*

*:

*5

whenever the 5 matches i.e. at

05, 15,

25

minutes etc

Every hour:

******21

*

*1*

*

*:21

sounds

at

21

mins past

every

hour

Every

24

hours:

****1730

*

*1*

*

1 7

:30

at

17:30 every day

Every minute for ten

****093

*

*1*

*

09:3

*

from 9.30 am to 9.39 am

minutes: Every minute for

an

****14**

*

*1*

*

1 4 : * *

from 14.00 to 14.59

hour: Every minute for ten

******3

*

*1*

*

*:3

*

from 30 minutes to

39

minutes ten every hour:

minutes ten past the hour every hour:

Once a month:

**151015

* *

II

5

1 0

:1

5

On

the 15th

of

the month

at

10.15 am

Every day for a month:

06**1415

061*

*

1 4

:1

5

At

14.15 every day in June

A specific time:

11111111

1 1

II

1

1 1 : 1 1

On

Nov

11

at

11.11

NOTE:

Only the asterisk or question mark should be used

as

a wildcard character.

The time should be checked before exiting from the System Display

as

the PX-8

carries out a comparison between your string and the string output by the clock.

If

the alarm does not go

off

when you expect it to, check the System Display

to

see

that the time you entered was correct.

iii)

Setting the WAKE junction

The wake function makes it possible to automatically turn on the power

and/or

start a program

or

execute a command

at

any desired time.

Note that the WAKE or ALARM cannot be used together.

The procedure for setting the WAKE time

is

the same

as

that for setting the

ALARM time, except that option 3

is

taken instead

of

option 2 (Fig 2.17). All

the wildcard options can be used in the same way.

2-30

The message string (option 4 Fig 2.17)

is

used

to

name a program which

is

to

be run.

It

is

used in a similar way

to

the AUTO START string (see the next

module). The string input into the WAKE message

is

used as

if

the characters were typed from the keyboard when the WAKE function switches the PX-8 on. Thus the message

"A:PROG"M"

will run the

CP/M

COM file

"PROG"

on

drive A: when WAKE switches the PX-8 on. The two characters

at

the end

are a CTRL-M written as

""M".

This

is

the carriage return character. Just

as nothing will happen

if

you do not press the I

RETURN

I key when typing in

a file name, so missing the

""M"

from the end

of

a file name in a message

string

will

normally cause the PX-8

to

wait until the auto power

off

time

is

reached and then switch off.

For

the options and rules

to

be followed in setting up a WAKE string,

see

the

next module (the AUTO START string). Note

that

the WAKE string

is

entered as a message under the ALARM/WAKE option and NOT under the AUTO START string. The AUTO START string does not operate

if

the WAKE

is

ex-

ecuted.

When you

tryout

the WAKE function, remember that it won't work unless

you switch

off

the PX-8 before the WAKE time

is

reached. Set

aWAKE

time

for a couple

of

minutes ahead and then enter a WAKE string. As an example

you could use

"DIR"M"

to display a directory

of

the current drive. Make sure

you have switched

off

the MENU for this experiment

or

one

of

two error con-

ditions will arise. First,

if

BASIC

is

resident when you switch off, it will still

be there when the PX-8 WAKEs up. When the string

"DIR"M"

is

encoun-

tered it will not be recognised by BASIC

'Ok'

prompt.

Refer to the rules in the next section on setting the AUTO START string for details

of

how

to

overcome this.

IMPORTANT: In adding the" "M" to the end

of

the message string in WAKE,

the

"M"

must be upper case.

If

the message string following

the"

< WAKE

STRG>"

label has a

"-"

character

at

the end you have entered

"m"

and

not

""M"

.

The action taken when the WAKE time

is

reached differs according

to

the state

of

the PX-8 when the wake time

is

reached.

•

If

the power

is

turned on:

The WAKE behaves as

if

it were

an

ALARM. This is

to

prevent the program

initiated by the WAKE string from interrupting the task in hand when the WAKE

2-31

time

is

reached. The speaker warbles and the display changes in the same way

as

if

an alarm was sounded. Instead

of

the WAKE string being a command

string it

is

simply printed as a message string. The screen shows that a WAKE

time (and not

an

ALARM time) has been reached when it appears as shown

in Fig. 2.20, for example.

***

MENU

screen

***

00/00/00

(SUN)

00:12:24

54.5k

CPIM

ver

2.2

PAGE

1/1

B:BASIC Good

morning!

B:BASIC

COM

Fig.

2.20

The appropriate action can be taken, treating the WAKE as an alarm message. The same criteria apply for termination

as

apply

to

the ALARM time being

reached.

•

If

the power

is

turned off:

The action taken will depend

on

the state

of

the PX-8 when switched off.

•

If

the PX-8

is

in the continue mode:

The power will be turned

on

and the program which was interrupted by switch-

ing

off

will be continued. There will be no message, the computer will simply

behave

as

if

it had been turned

on

manually. ANY WAKE STRING WILL BE

IGNORED.

•

If

the PX-8

is

in the restart mode:

a) The power will be turned

on

and the WAKE string executed as

if

it had been

typed in

at

the keyboard.

b)

If

no WAKE string

is

specified the situation will be equivalent

to

the power

being switched

on

manually, except that it will have been switched

on

automatically. Although the speaker will sound, there may not be anyone near the computer

to

notice that this has occurred. The PX-8 will then switch

itself

off

when the auto-power-off time

is

reached.

c)

If

no WAKE string is specified

but

an AUTO START string has been en-

tered, the AUTO START string WILL BE IGNORED.

iv)

AUTO

START

string

The AUTO START string

is

used

to

set a string which will be entered as

if

it

had been typed from the keyboard when the PX-8

is

switched on.

2-32

The AUTO START string will be ignored

if

the PX-8

is

switched

on

in the con-

tinue mode. When the computer has been switched

off

in the continue mode,

this

is

because the computer has been stopped in the middle

of

a program exe-

cution. To start up again with a new program could destroy valuable data.

To

set the AUTO START string, press the

@l

key when the System Display

is

as shown in Fig. 2.13a

or

b. '

The prompt changes as follows.

***

SYSTEM

DISPLAY

***

03/01/84

(THU)

12:01:34

<MENU>

<RAM

DISK>

009

kb

<AUTO

START>

<USER

BIOS>

000

256 b <MCT

MODE>

stop,

nonverify

<COUNT>

65535

<MENU

DRIVE>

CBA

<MENU

FILE> 1

.COM

2.

3 • 4 •

-

Select

number

or

ESC

to

return.

<AUTO

START>

l=off

2=assign

Fig.

2.21

To assign the string, press the

[1J

key and the prompt changes as follows:

***

SYSTEM

DISPLAY ***

03/01/84

(THU)

12:01:34

<MENU>

<RAM

DISK>

009

kb

<AUTO

START>

<USER

BIOS>

000

256 b <MeT

MODE>

stop,

nonverify

<COUNT>

65535

<MENU

DRIVE>

CBA

<MENU

FILE> 1

.COM

2.

3 • 4 •

-

Input

auto

start

string,

ESC

to

cancel.

Fig.

2.22

As an example

of

how

to

use the AUTO START string from the System Dis-

play type 3

to

select the AUTO START option.

When lines 6 and 7 show the options as in Fig 2.21 take option 2 and then type in the following string: "B:BASICI\M". This assumes the BASIC interpreter ROM

is

in the socket assigned

to

drive

B:

and should be changed

to

"C:BAS-

ICI\M"

if

it

is

in the C: drive socket.

Press the

I

RETURN

I key when the string has been correctly entered.

Now ensure that the MENU

is

off

by entering option 4

on

the System Display

and then taking option 1. MENU

is

described in the next module.

Switch the PX-8

off

in restart mode, i.e. simply switch

off

WITHOUT holding

down the

I

CTRL

I key.

2-33

Wait a

few

seconds then switch it

on

again. The screen will clear and place you

on

the

CP/M

command line and the characters

"B:BASIC"

will be printed next to the system prompt. Since the carriage return has been added by the PX-8 from the

"AM"

characters

at

the end

of

the

AUm

START

string, this will then be executed and about ten seconds later the BASIC program menu will be displayed.

To cancel the auto start string, press theWkey when the display

is

as shown

in Fig. 2.21, and the display will change as shown in Fig. 2.13b.

To change the AUTO START string, carry

out

the procedure for assigning a

string. The previous string will be displayed and can be edited.

It

is

possible

to delete the character to the left

of

the cursor but not to insert characters. Typing

over a character replaces it. In many cases it

is

simpler

to

cancel the string and

then reassign another one.

v) Rules

for

setting

up

AUTO

START

and

WAKE

Strings

1)

If

no carriage return

is

entered

at

the end

of

a string meant to be executed,

the PX-8

will

wait for the next character to be typed manually when switched

on. This

is

the case either when the string

is

a WAKE string

or

an

AUTO

START string. A carriage return should be entered as the pair

of

characters

"AM"

and not

as

a lower case

"Am".

If

the characters have been entered

as

"Am",

the string will

show"

-"

instead

of

the correct

"AM"

.

If

the carriage return

is

not present, the PX-8 will wait until the auto-power-

off

time

is

reached and then switch off.

2)

If

the WAKE string switches

on

the PX-8 the AUTO START string will be

ignored even

if

the WAKE string

is

blank.

3)

If

the PX-8 is restarted, either manually

or

by the WAKE function, and the

computer

is

in the continue mode the WAKE

or

AUTO START strings will

be ignored.

4)

If

the PASSWORD

is

set the PX-8 will not be able to AUTO START or

use the WAKE string until the password has been correctly entered.

5)

If

the MENU (next module)

is

set then the AUTO START

or

WAKE string

will be printed next

to

whatever is on the command line. When the carriage

return

is

entered the complete string on.the command line is executed. Since

this includes the file name which

is

in the top left hand corner

of

the menu

2-34

list,

an

invalid command will almost certainly be present.

This can be overcome

if

the AUTO START

or

WAKE string backspaces over the file name entered onto the command line by the MENU. The control character for a backspace

is

CTRL-H. Thus

if

the MENU

is

likely to be set when the WAKE or AUTO START strings are used, add the following characters to the string:-"AHAHAHAHAHAHAHAHAHAHAH". Eleven characters are needed. Thus to run BASIC as in the example above, the WAKE or AUTO START string should be "AHAHAHAHAHAHAHAHAHAHAHB:BASICAM".

As

with

the <:arriage return the characters should be

"AH"

and not

"Ah".

It

will not matter

if

this string

is

entered when the MENU

is

inoperative, and

the PX-8 WAKEs

or

AUTO STARTs

on

the

CP/M

command line.

The best course

of

action

is

to

switch

off

the MENU

if

a WAKE or AUTO

START string

is

used.

6)

There

is

one case when it

is

not necessarily beneficial to switch

off

the MENU.

This

is

when BASIC

is

resident in memory and a number

of

programs are

loaded into the five BASIC program areas.

In

this case the AUTO START

or WAKE string would be set up either

to

run one

of

the loaded programs,

or to load a program from one

of

the disk drives.

The BASIC Reference Manual gives details

of

how to set up AUTO START

and WAKE strings under the AUTO START and ALARM commands

of BASIC. These examples can be used in the same way to enter AUTO START and WAKE strings directly through the System Display.

7)

Control Codes

OOH

to

1FH can be set using the combination

of

"A"

and

ASCII codes (40H to 5FH).

WARNING:

It

BASIC

is

resident and the A

UTOSTART

or

WAKE

string is not a BAS-

IC

program name (or even requests

BASIC

to be loaded),

an.

error will

be generated. Thus

in

setting up

WAKE

and A

UTOST

ART

strings, note

should be taken

of

the way tlie system

is

set up.

It

is best to set the system

up specially

for

the A

UTOSTART

or WAKE, so that errors do not occur.

2-35

d)

MENU module

When switching

on

the PX-8 it

is

sometimes difficult to find a particular pro-

gram among a number

of

others

on

a disk device. Many

of

them may not be

be relevant.

In

many cases the same program is used over and over again, and

like using the

PF

keys it

is

easier

to

press one key

to

load the program. The

MENU module simplifies the selection

of

a program by allowing the types

of

file names which are displayed to be limited, and allows programs from a mix-

ture

of

drives

to

be displayed together.

It

also allows the programs to be selected by movement around the displayed files using the cursor keys, and then running the program simply by pressing the

I

RETURN

I key.

The MENU

is

controlled by option 4

of

the System Display. Press the I

CTRL

I

and I

HELP

I key

to

turn

on the System Display. Now press the ~ key and lines

6 and

7 change to:

***

SYSTEM

DISPLAY

***

<RAM

DISK>

009

kb

<USER

BIOS>

000

256

b

<MENU

DRIVE>

CBA

03/01/84

(THU)

12:01:34

<AUTO

START)

<MCT

MODE>

stop,

nonverify

<COUNT>

65535

<MENU

FILE> 1 .COM

2.

3 • 4 •

-

Select

number

or

ESC

to

return.

<MENU>

l=off

2=on

3=drive

4=extl

5=ext2

6=ext3 7=ext4

Fig.

2.23

Press the ~ key and note how the label

"<

MENU>"

comes up

on

the

top right

of

the screen

on

the first line.

It

can be switched

off

using option 1

at

this level. Before actually displaying the MENU, it

is

necessary to select which

drives the files are to be chosen from and also which types

of

files are

to

be

chosen from those drives. Chapter 3 explains the types

of

files. As a first illus-

tration

of

the use

of

the MENU, choose option 3 and type

"BC"

and press

the

I

RETURN

I key. Note that these letters appear after the

label"

<MENU

DRIVE>

" on the left

of

the fifth line and mean that files will be chosen from

the

B:

and C: drives, i.e. the ROM drives.

In

order to select a type

of

file, take

option 4 and type

"COM"

and press the I

RETURN

I key. Note how the fifth line

has changed so that the first file name extension (next

to

the label

"<

MENU

FILE>")

has changed

to

"COM".

Now press the I

ESC

I key and the System Display returns to the first state. The

MENU mode

is

set and the MENU screen will be displayed when the power

switch

is

next turned on, or a warm start

is

made.

2-36

Turn

off

the power switch and then turn it

on

again. The speaker beeps and

the following screen

is

displayed:

***

MENU

screen

***

03/01/84

(THU)

12:00:52

54.5k

CPIM

C:PIP C:PIP

COM

C:STAT

COM

C:SUBMIT

COM

C:FILINK

COM

C:TERM

COM

C:CONFIG

COM

Fig.

2.24

ver

2.2

PAGE

1/1

C:

XSUB

COM

B:BASIC

COM

The MENU screen

is

divided into three sections as shown below.

1 line Header

~--------------------------------------------~

1 line Command line

~--------------------------------------------~

6 lines

File name area

Fig.

2.25

Header section The header section consists

of

the title

"*

* * MENU screen * * *

",

date,

day

of

the week, time, CP 1M comment, current menu page and number

of

menu

pages.

If

the number

of

files' excedds

120,

"*"

will be displayed

at

the end

of

header section.

Command line The command line section displays the currently selected file name, adding any

COM file name

if

the file selected requires a COM file for execution. The Sys-

tem Display

is

used

to

decide exactly what

is

printed

on

this line for each file,

and the method

of

setting it

is

explained in the next few pages.

File name area The lower part

of

the screen shows all the file names set up on the System Dis-

play, chosen from the selected drives and the selected file extensions.

i)

Using

the

MENU

The command line duplicates the name

of

the file in the top left

of

the file area

and,

to

highlight the selected file, the name in the file area flashes.

It

is

possible

to

change the selected file by using the cursor keys. Pressing the right arrow

key moves

to

the right along a row, and then from left

to

right

on

the next

2-37

line. When the last filename

is

reached, the first one

of

the next line

is

selected

to be displayed on the command line. The left arrow moves

to

the left in the

same way. The up and down cursor keys allow movement in a column but

do not move into another column. '

When a file name

is

on the command line, simply pressing the I

RETURN

I key

will run that particular program. As

an

example, move the cursor keys until

~he

file STAT

is

on

the command line. As will be seen in Chapter 3, STAT

IS

a program which gives STATistical information about the status

of

the com-

puter and the disk drives. When STAT.COM (with its appropriate drive name

prefix)

is

flashing, note that the drive name followed by STAT

is

printed on

the command line. Press the

I

RETURN

I key. The screen clears and the STAT

program shows information such

as

the following:

A)C:STAT

A:

R/W,

Space:

81:

C:

RIO,

Space:

331:

H:

R/W,

Space:

291:

A)

Fig.

2.26

The second line

of

the screen shows the

CP

iM

prompt and then the command

line

as

would have been typed in had the STAT program been run directly from

CP

1M. This display shows a situation with the

CP

1M

utilities in drive C: and

thus the drive name C: would be displayed before the filename. After a

few

s~conds,

when the program has collected the information, the other lines are

dIsplayed. These show the space left

on

the various drives and whether they

can be written to

(R/W)

or

are read only (RIO). The

CPIM

prompt

"A>"

is

then followed by the cursor.

NOTE: In this case ending the program has returned the user to the

CPIM

command

line. Sometimes when a program ends it will return to the MENU.

If

the

STAT

program had returned

you

to the MENU, all the information would have been

erased from the screen before it could have been read.

Return to the MENU by using either the

I STOP I key or I

CTRl

I -

[g

and again place the STAT program on the command line. When the selected file has been placed

on

the command line, the cursor

is

placed

to

the right

of

the file name

and

is

seen

as

a flashing underline character. This allows further parameters

to

be added from the keyboard. As an example

of

this use

of

the MENU, with

2-38

the STAT program

on

the command line, type in DEV: and then press the

I

RETURN

1 key. As

is

explained in Chapter 3, this shows the physical devices as-

signed

to

the four logical devices. As before the screen will clear and show the

command as

if

it were typed in from the

CP

1M

command line, before display-

ing the information a

few

seconds later. A possible display

is

shown in fig 2.27

below.

A)C:STAT

DEV:

CON:

is

CRT:

RDR:

is

UR1:

PUN:

is

UP1:

LST:

is

LPT:

A)

Fig.

2.27

ii) Setting the file extensions on the System Display

In setting the file extensions

on

the System Display care has

to

be taken in set-

ting up files which are

to

be run

as

subsidiary files

of

a main COM file. The

most common case

of

this

is

the use

of

BASIC files with the extension" .BAS" .

Other examples

of

extensions

to

filenames which denote subsidiary files are

".OVR"

and

".DAT".

Attempting

to

run these files without the appropriate

COM file will result in

an

error. As an example

of

setting up the MENU

to

run subsidiary files, the following procedure should be used to set up BASIC

files. Enter the System Display and choose option 4, the MENU option.

Now edit the second extension by choosing option

5.

To specify the subsidiary file type its extension (for BASIC files the extension is

".BAS")

followed by the filename

of

the COM file

of

which it

is

a subsidi-

ary files. This

is

the reverse

of

normal

CPIM

conventions, but

is

necessary

to

display the extension correctly

on

line 5

of

the System Display. Lines 6 and

7 would thus display:

2-39

***

SYSTEM

DISPLAY ***

03/01/84

<THU)

12:('1:34

<MENU>

<RAM

DISK>

009

kb

<AUTO

START>

<USER

BIOS>

000

256 b (MCT

MODE>

stop,

nonvRrify

<COUNT>

65535

<MENU

DRIVE>

CBA

<MENU

FILE> 1

.COM

2.

3 • 4 •

-

Input

extention

name

2,

ESC

to

cancel.

BAS

Fig.

2.28

When the

L!!rt![1!&]

key is pressed, the right

hand

side

of

the fifth line will show

<MENU

FILE>

1.COM

2.BAS

3 .

4.

However,

if

a file name is chosen with the extension

".BAS",

for example

"a:ZZZZ.BAS"

the command line will show

b:basic

a:ZZZZ.BAS

and

when the I

RETURN

I key is pressed, BASIC will be loaded first

and

then the

subsidiary file

run.

WARNING:

If

the

MENU

is used to run a program this way, since the

BASIC

inter-

preter

is loaded as

well,

any programs which

are

in the five program areas

will be lost.

A way to overcome this is described in the following section.

iii)

Using

BASIC

from

the

MENU

Details

of

using BASIC

on

the PX-8 are given in the BASIC Reference Manu-

al. When BASIC has been loaded

and

the PX-8 is switched

off

the

first file

from the disk drives will

not

be flashing. Instead the file area will show

"BASIC

(resident)" in the

top

left corner which will be flashing,

and

the command line

will be blank. Simply pressing

I

RETURN

I

at

this stage will cause the BASIC

Pro-

gram Menu

to

be turned

on.

Any

programs in the five program areas can be

run

as described in the BASIC Reference Manual.

If

BASIC

is

resident, the above method

of

selecting a BASIC

program

from

the

MENU

will load the BASIC interpreter

and

destroy the programs in the five BASIC program areas. The following method will allow a BASIC program to

be selected

from

the

MENU

and

run

while BASIC is resident.

i) Use either the

MENU

or

the

CP/M

command line

to

load BASIC.

2-40

ii) Login

to

one

of

the

program

areas

and

type

"system"

or

use PF8 (shifted

PF3)

to

return

to

the

CP

1M

command line

or

the MENU.

iii) Either

on

the

MENU

or

CP

1M

command line type:

SAVE 9 A:GO.COM

The reason for doing this is explained in Chapter 3 under the SAVE command.

iv) Enter the System Display

and

using option 5

on

the MENU, alter the ex-

tension

to

read:

BAS A:GO

This uses the

COM

file

"GO"

as the main file, with the BAS file as the subsidi-

ary file.

When a file with the

"BAS"

extension is chosen from the MENU,

if

AND

ONLY

if

BASIC IS RESIDENT, the

MENU

command

line will show:

A:GO A:ZZZZ.BAS

when the file

"A:ZZZZ.BAS"

is chosen from the menu,

and

the program will

run

directly in BASIC in program

area

one.

Note however,

that

there is no need

to

resort

to

this method

if

BASIC is resi-

dent

and

the WAKE

or

AUTO

START strings are used.

The

MENU

module is activated under one

of

the following conditions:

1)

The MENU mode is specified

and

the

AUTO

START string is

not

specified in the System Display,

and

power is

turned

on

by the power

switch

or

when the wake time is reached.

2)

The

I STOP I

or

I

CTRl

I

and

[g

keys are pressed together when

an

appli-

cation program which has been entered from the menu mode

is

being

executed

or

the

"SYSTEM"

statement

is

executed in the BASIC mode.

2-41

Operation

of

the MENU module is interrupted in one

of

the following cases.

1)

When the alarm or wake time

is

reached.

2)

When the I

CTRL

I and I

HELP

I keys are pressed together. (The system

module

is

activated.)

3)

When the I

CTRL

I and I

PF5

I keys are pressed together. (The screen

dump module

is

activated.)

The MENU module

is

started

at

the state

at

which

it

was interrupted when the

MENU mode

is

returned

to

from one

of

the above conditions.

The MENU mode is terminated in one

of

the following cases:

1)

When

an

application program

is

selected and the I

RETURN

I key

is

pressed.

2)

When the AUTO POWER OFF time

is

reached.

3)

When power failure

is

detected.

4)

When the power switch

is

turned off.

5)

When the I ESC I key

is

pressed. (The screen clears and the

CP

1M

system

prompt appears

on

the screen.)

2-42

e) Microcassette mode The System Display

is

used

to

operate the Microcassette drive manually and

also

to

check on the Microcassette mode settings. Full information

on

the

Microcassette drive

is

given in Chapter 4.

i)

Setting the Microcassette mode

To specify the Microcassette mode, choose option 5

on

the System Display by

pressing the

lID

key.

Lines 6 and 7

of

the screen then change to:

***

SYSTEM

DISPLAY ***

03/01/84

(THU)

12:01:34

<MENU)

<AUTO

START)

<RAM

DISK)

009

kb

<USER

BIOS)

000

256

b

<MENU

DRIVE)

CBA

<MCT

MODE)

stop,

nonverify

<COUNT)

65535

<MENU

FILE) 1 .COM

2 .BAS

3.

4 .

-

Select

number

or

ESC

to

return.

<MCT)

l=stop

2=nonstop

3=verify

4=nonverify

Fig.

2.29

The stop and nonverify modes are automatically set after system initialization. Pressing the

[)

key sets the stop mode, pressing the ~ key sets the nonstop

mode, pressing the

@]

key sets the verify mode and pressing the ~ key sets

the nonverify mode. Full details

of

the significance

of

these terms are described

in Chapter 4 where the operation

of

the Microcassette drive

is

covered in depth.

The current settings for the Microcassette operation are shown

on

the right

of

the fourth line

of

the System Display, following the

label"

< MCT

MODE>

" .

This line also shows the position

of

the tape counter, following the

" <

COUNT>"

label.

To return to the screen shown in Fig. 2.13b, press the

I ESC I key.

ii)

Manual operation

of

Microcassette drive

The System Display

is

also used

to

allow the Programmable Function keys

to

operate the Microcassette drive manually. The function assigned to each

of

these

keys

is

indicated

on

the 8th line

of

the system display shown in Fig. 2.13b.

Two

of

the keys are assigned for fast winding

of

the tape forward and back-

wards. These are the

i

PF1

I and I PF4 I keys which wind the tape

on

« < - )

and rewind the tape

on (-> > ) respectively.

The

I PF2 I key

is

used

to

play the tape at normal speed through the speaker.

2-43

The I PF7 I (shifted I

PF2!

) key

is

used to mount a tape, i.e. make it ready to

be read from

or

written to by reading the directory into memory. When the

tape

is

used first, the I PF8 I (shifted I PF31 ) key can be used

to

initialize the tape

by storing space for a directory.

It

is

equivalent to formatting a conventional

disk. The

I PF91 (shifted

,PF4')

key

is

used to erase data from a tape. It does

this from the current position

of

the tape.

The

I

PF5!

key

is

used

to

reset the tape counter

to

zero. The current position

of

the counter can be seen

on

the right

of

line 5

of

the System Display next

to

the"

<COUNT>"

label.

The

I PF31 key marked with a

1m

character

is

the key

to

stop the cassette.

TO STOP

THE

MICRO CASSETTE IN

AN

EMERGENCY press the I CTRL !

and I

STOP

! keys together.

If

a Microcassette has been mounted, the only key which is assigned

is

,PF6

I

(shifted

~

). This will show the string

"remove"

which will allow the tape

to be removed from the cassette drive. It

is

worth getting into the habit

of

check-

ing the status

of

the cassette tape in the Microcassette drive, by inspecting the

System Display BEFORE removing a tape from the drive.

If

a tape has been

mounted, the eighth line will only show the word remove.

If

a tape has been mounted, when the I PF6 ! (shifted , PF1 I ) key

is

pressed, the

screen will clear and show the message

"remove"

in the top left hand corner

of

the screen.

If

the tape has simply been read this will flash up momentarily,

and the System Display will be redisplayed but with the eighth line showing

the assignments for an unmounted tape.

If

the tape has been written to, the revised directory on the tape will have to

be written back

on

to the tape from memory. The tape will thus wind back

to the beginning, and then record the updated directory. When this has been

carried out, the System Display

will

be redisplayed but with the eighth line show-

ing the assignments for an unmounted tape.

/I\.

WARNING:

W

Do

not

change a tape

and

attempt to write to another one, without first

removing the first tape and mounting the new one. Failure to observe this

will almost certainly mean that data on both tapes will

not

be

able to be

read,

and may also remove valuable data

from

the second unmounted tape.

2-44

f)

The screen dump module

The screen dump module outputs the contents

of

display screen to a printer.

It

is

activated by pressing the I PF5 I key together with the , CTRL I key

or

calling

the BIOS SCRNDUMP routine in

CP

1M

mode. In screen modes

0,1

and 2 data

is

sent to the printer in ASCII format, and in screen mode 3 in bit image format.

Printing stops when the ,

CTRL I and,

STOP

Ikeys

are pressed simultaneously, the

power switch

is

turned

off

or power failure

is

detected.

If

the printer

is

not ready, the module waits until it becomes ready.

NOTE: If

there is

no

printer attached to the PX-8, this creates a lock-up

of

the sytem.

If

this happens, press ,

CTRL

!

and

,

STOP

I keys together. User can resume his ses-

sion with

no

loss

of

data.

2-45

2.2.4 Alternative reset sequences

Situations occasionally arise where the PX-8 ceases

to

respond to any instruc-

tions from the keyboard when you expect it would. Even the I

STOP

Ikey

does

not appear to work. The computer

is

said

to

be

"hanging".

This should not

be confused with the situation where a program

is

processing data and takes

seconds

or

even a minute

to

reach a situation where the user can input data

again. When the system appears

to

have hung, it

is

sometimes possible to gain

control by switching off, waiting a

few

seconds and switching

on

again.

However, in most cases it

is

necessary to RESET the computer. There are a

number

of

methods

of

resetting, which affect the system parameters to a differ-

ent extent.

a) SUB-CPU RESET

This

is

the most drastic reset procedure and

is

carried out as described in

sec-

tion 2.1.3.

It

must be carried out

if

the battery

is

changed,

or

if

all other reset

methods fail.

b) INITIALIZATION RESET

This reset

se

uence

is

achieved by holding down the right-hand SHIFT

and

G~~~

keys while pressing the reset switch

on

the left

of

the PX-8

using the tip

of

a ball point pen

or

other similar implement. See fig. 1.1c for

the position

of

the reset switch.

This method

of

resetting,

is

for practical purposes as drastic as the sub-cpu reset

and will cause loss

of

the current program, data and possibly destroy the RAM

disk. When this reset method

is

used, the initialization procedure outlined in section

2.1.3 from item

v)

onwards will have to be carried out.

c)

SIMPLE

RESET

The least drastic method

of

resetting the PX-8

is

to simply press the reset switch

on

the side

of

the computer using the tip

of

a ball point pen etc. In most cases

very little harm will have been done

to

data, and most

if

not all variables in

a program will probably still be intact. A number

of

system parameters

will

be changed and details

of

these are shown in table 2.3.

This method

of

resetting should be tried first.

2-46

d) Summary

of

RESET actions

In

resetting the computer it

is

as well to be aware

of

the parameters which are altered by the reset action. The following table shows which settings are altered. Since these are normally the default settings

of

the system, these are shown also.

Table 2.3

SIMPLE

NUM/

SUB-CPU CHANGE

RESETPARAMETER DEFAULT

GRPH

RESET

WITH

ALARM/WAKE

off

-

d

d s,b

AUTO

POWER

OFF

10

mins

-

d

d c,b

AUTO

START

off

-

d d

s,b

CHARACTER SET

DIP

switch setting

d d d

CURRENT DRIVE

A: d

d

NOTES

CURSOR

TYPE

flashing block

d d d

c,b

DATE/TIME

NOTE 1 -

u

u c,b

DISK ASSIGNMENTS NOTE 2

d d d c

PF

KEY DISPLAY

off

d

d c,b

PF

KEY STRINGS

NOTE 3 d

d

d c,b

I/O

BYTE (03H) 1OI0100lB

d d d NOTE 9

KEYBOARD

NOTE 4 d

d

d NOTE 4

MENU

on

-

d d s

MENU DRIVES

CBA

-

d

s

MENU FILE

EXT

.COM

-

d d s

MICROCASSETTE

COUNT

-

destroyed destroyed s,b

STATE

unmounted d d d s,b

STOP MODE stop

d

d s,b

VERIFY MODE

non-v~rify

d d d s,b

PASSWORD

off

d d d

s

PRINTER

RS232C d

d

c

RAM DISK SIZE

9K

-

u u

c

RS232C

NOTES

d

c

SCREEN MODE

mode 0 d d d c,b

SERIAL INTERFACE

NOTE 6 d

d

c

USER BIOS SIZE

o pages

-

u u

c

USER DEFINED CHARS

EO,EI

del, cr symbols d

d d NOTE 7

E2 -

FE

NOTE 7

- - -

WINDOW

tracking mode d

d.

d s,c,b

..

KEY

TO

abbreVIations:

d

= default mode u = set by user on reset

s

= System Display c = CONFIG program b = BASIC

* Some functions can also be changed using ESCAPE code sequences as

described

in

Appendix A.

2·47

NOTE

1:

The DATE and time are set

to

the default 00/00/00 00:00:00 with the day as

zero (Sunday), and the user

is

asked to change them on reset.

NOTE

2:

The disk assignments for the default mode are shown in the explanation

of

the

CONFIG program in Chapter 3. NOTE

3:

The default Programmable Function strings are shown in the explanation

of

the CONFIG program in Chapter

3,

and in section 2.2.1 above.

NOTE

4:

The default setting

of

the keyboard has the auto repeat start time set

at

650

ms and the repeat interval

at

75

ms. The keyboard

is

normal, in that all CAPS

LOCKS etc are switched off. Any jumps to user functions using the

I

CTRL

I

keys and the I ESC I ,I PAUSE' and

'PF1

,

to

'PF4

I keys are set to a return.

NOTE

5:

The default RS232C settings are shown under the CONFIG program

of

Chap-

ter

3.

NOTE

6:

The default setting

of

the Serial Interface are given in the explanation

of

the

use

of

the CONFIG program in Chapter

3.

NOTE

7:

The User Defined Characters ASCII codes 224

to

254 (hexadecimal

EO

to

FE)

can be set using control code sequences

as

described in Appendix A. They can

also be set from BASIC, and a program

to

do this

is

shown in Appendix H

of

the BASIC Reference Manual.

The first two characters 224 and

225

(EOH

and

EIH)

have the default symbols

for delete

".1"

and a carriage return assigned

to

them. These characters are

also frequently reset to the defaults

at

other times for example

on

power up. The character defined into ASCII code 226 (E2H) may also be corrupted on a reset.

NOTE

8:

The current drive

is

set by the applications program or from the

CP/M

com-

mand line. NOTE

9:

The use

of

the

I/O

byte

is

described in Chapters 3 and

5.

2-48

Priority

of

system reset

When a lock-up

of

the system occurs, reset the sytem according to the follow-

ing priority.

1.

Press I

STOP

I key.

2.

Press'

CTRL

, - I STOP' keys.

3.

Press Reset switch

on

the left hand.

4.

Press Reset switch while holding down ,

SHIFT'

-

IG~~WHI

keys.

(or press Sub

CPU

Reset switch)

2.2.5 Changing parameters

For

a description

of

how to change the parameters

see

the CONFIG program

in Chapter 3, and section 2.2.3a. Details

of

which parameters are changed by the CONFIG program and which by the System Display can be found from table 2.2.

2-49

2.2.6 The Screen

of

the PX-8

When you view the LCD screen

of

the PX-S, you are looking

at

a window

on

a much larger screen. The screen displayed

on

the LCD

is

known

as

the real

screen. This

is

S lines high by

SO

columns. The operating system works with

a much larger screen, a screen

of

up

to

40

lines and

SO

columns. The real screen

then displays a window

on

this larger screen (the virtual screen), which

is

called

the virtual screen window.

Virtual screen

window

Real sc reen

Function key display area (optional)

There are also four different screen modes (including a graphics mode) which

show different types

of

display. In all but the graphics mode there are two vir-

tual screens.

This section outlines the different screen modes and shows how

to

use them. Changing between different screen modes can be achieved using the CONFIG program described in Chapter

3.

It

is

also possible

to

change the screen modes using BASIC commands, and the BASIC Reference Manual contains a practical guide to the screen modes in section 2.14.

It

is

unlikely that you will use the different screen modes in the

CP

1M environ-

ment unless a particular applications program has made use

of

them. However,

there are certain benefits

to

be obtained by learning

to

use the tracking and non-tracking modes, and to understand the virtual screens. As these would be utilised mainly in screen mode 0, a detailed explanation

is

given in the follow-

ing outline

of

this screen mode.

2-50

i)

The Screen Modes

There are four screen modes possible with PX-S. Three

of

them are text only

screens, and the fourth

is

a mixed text and graphics mode. The difference be-

tween the modes

is

primarily the way the real screen presents the information

written

on

the virtual screens.

a) Screen mode 0 (the 80 column text screen mode) This screen mode has two virtual screens each with

SO

columns. The number

lines

on

these screens can be set by the user provided that the sum

of

the num-

ber

of

lines does not exceed

4S

and there are at least S lines (i.e. one real screen-

ful

of

lines) on each screen.

n1

Virtual Screen 1

1----

80

columns

-----0-1

r

n2

lines

Virtual Screen 2

+-----80

columns

---

......

0011

1.L..-----...J

Conditions: n 1

2:

8

n22:8

h=7

or 8

n1

+n2;::;;48

The virtual screen window moves over the virtual screen

to

display a part

of

the virtual screen on the real screen. This movement

is

known

as

scrolling. When

the real screen moves over the virtual screen, scrolling with the cursor, this

is

known as tracking mode. Tracking mode can be switched

off

by pressing the

I SCRN I key

(I

SHIFT

1+

I INS

I).

When this

is

done the cursor moves over the

virtual screen while the real screen stays

at

the same place

on

the virtual screen.

The real screen becomes locked in a particular position

on

the virtual screen.

The following illustration will show the effect

of

scrolling in the tracking and

non-tracking modes.

It

assumes that the virtual screen size

of

24

lines

on

each

2-51

screen has been set. The CONFIG program described in Chapter 3 can be used to check this and reset it

if

necessary.

Go to the System Display and switch

off

the MENU. Exit from the System Dis-

play to display the

CP

1M

command line.

If

the screen

is

not

clear, it may be cleared by pressing the I CLR I key

(I

SHIFT I

+[QKJ),

or

typing CTRL-L by holding down the I CTRL I key while pressing

the

"[!J"

key. In either case the display will show

"I\L"next

to

the

CP/M

sys-

tem prompt. Thus

if

the currently logged in drive

is

A:, the following will be

displayed:

When the

I RETURN I key

is

pressed, the screen will clear and show a question

mark in the

top

left hand corner. This

is

because

CP

1M

does not understand

I CTRL I -

[!J

, as a command. After printing a blank line the system prompt

is

printed again, with the cursor to the right

of

it.

Now obtain a directory

of

the utility ROM by typing

"DIR

C:"

if

the ROM

is

in ROM socket 2,

or

"DIR

B:"

if

it

is

in ROM socket

1.

For the purposes

of

this illustration it will be assumed

that

it

is

in ROM socket 2 as supplied.

The display will show:

?

A>dir

c::

C:

PIP

COM

STAT

C: FILINK

COM

TERM

A>_

COM

SUBMIT

~OM

XSUB

COM

CONFI6

COM

Because only two lines and a

new

system prompt have been written on the screen,

the screen has

not

needed to scroll. However

if

the command

is

typed again,

the

"?"

will scroll

off

the

top

of

the real screen, and show the following:

A>dir

c::

C:

PIP

COM

STAT

COM

:

SUBMIT

COM

XSUB

COM

C:

FlUNK

COM

TERM

COM

:

CONFI6

COM

A>dir

c::

C:

PIP

COM

STAT

COM

:

SUBMIT

COM

C:

FlUNK

COM

XSUB

COM

TERM

COM

:

CONFI6

COM

A>I

2-52

The

"?"

is

still the first character on the virtual screen. This can be seen in

one

of

two ways. Pressing the I CTRL I and

[!]

cursor key will display the first

lines

of

the virtual screen because these keys move the real screen backwards

one page (i.e. one real screen)

on

the virtual screen. Pressing the space bar (or

any other key) will return

to

the original display. Alternatively the screen can

be scrolled up by pressing the

I SHIFT I and

[±]

cursor key. Again pressing

the space bar or another key will return the real screen

to

show the cursor.

To show the effect

of

this sequence

of

operations in non-tracking mode, first

clear the screen again using

I CTRL I -

[!J

or

the I CLR I key. Then press the

I SCRN I key

(I

SHIFT I +

~).

Nothing will appear

to

happen. Now obtain

two directories

of

the utility ROM in drive

C:

by typing

"DIR

C:"

as before.

The screen will show:

?

A>dir

c::

c:

PIP

COM

STAT

COM

SUBMIT

COM

,

XSUB

COM

C:

FlUNK

COM

TERM

COM

CONFI6

COM

A>dir

c::

C:

PIP

COM

STAT

COM

SUBMIT

COM

XSUB

COM

C:

FlUNK

COM

TERM

COM

CONFI6

COM

Note how the

"?"

on the first line remains visible in contrast to the same se-

quence

of

operations in the tracking mode. This time the cursor and

CP

1M

system prompt has disappeared

off

the real screen. They are further down the

virtual screen just outside the window. They can be seen by pressing the

I SHIFT I

+

[±]

cursor key

to

move the screen up. This leaves the real screen window

locked on these particular eight lines, so that typing

"DIR

C:"

again will write

the directory outside the real screen. Pressing the

I SCRN I key again will cause

the tracking mode

to

be restored and the screen will move up to show the cur-

sor. When returning to tracking mode the cursor

is

positioned in the centre

of

the screen and so the screen will appear as follows:

A>dir

c::

C:

PIP

COM

STAT

C:

FILINK

COM

TERM

A>

•

COM

SUBMIT

COM

XSUB

COM

CONFI6

COM

2-53

COM

Now press the I RETURN I key ten times. This will almost reach the bottom

of

the virtual screen. Press the I CTRL I and

[!]

key to move

to

the bottom

of

the virtual screen. Note

that

there are still two free lines

of

the virtual screen

with nothing printed

on

them.

Move to the top

of

the virtual screen by pressing the I CTRL I and

[!]

key twice.

Note

that

the first character the

"?"

is

still present. Lock the screen into non-

tracking mode by means

of

the I SCRN I key. Now type

"OIR

C:"

again. This

will write the directory

of

disk C:

on

the bottom

of

the virtual screen next to

the cursor,

and

then print a new

CP

1M

system prompt. However, as there are

not

enough lines

on

the virtual screen the whole virtual screen must scroll up

one line. This causes the window

at

the

top

of

the screen to change. The line

containing the

"?"

character

is

pushed

off

the cap

of

the virtual screen, and

lost forever. The

top

8 lines

of

the virtual screen are still displayed

on

the real screen, but they are 8 new lines now that scrolling has occurred. Return to tracking mode by pressing the

I SCRN I key again and the bottom

of

the virtual screen,

containing the cursor will be shown, with

the

directory

of

drive C: and the new

CP

1M

system prompt.

So far only one virtual screen has been used.

It

is

possible

to

move onto the

second virtual screen by using the

I CTRL I and 8 key,

and

back

to

the first

virtual screen using the

I CTRL I and

[B

key. The two screens can be written

to

independantly, although there

is

no

guarantee

that

all applications software

will allow you

to

use the second virtual screen

or

scroll or go into non-tracking

mode.

Switch

to

the second virtual screen using the I CTRL I and 8 keys. The screen

should be blank. Type

"OIR

B:"

and contents

of

the directory

of

the

B:

drive

will be printed.

If

you switch back to the first virtual screen using the I CTRL I

and

[B

keys, the screen will be exactly as you left it. Clear it with a

I CTRL I -

[IJ

or by using the I CLR I key and then go back

to

virtual screen 2

using the

I CTRL I and 8 key. Note that the display has not been changed.

One use

of

the two virtual screens

is

to store data. For example, frequently one

needs to know the contents

of

the directory

of

a disk.

Go

to

virtual screen 2,

and

print the directory

of

the disk there.

If

the program will allow it (and the

CP

1M

utilities such as

PIP

will) you can easily look

at

the second screen to

inspect the directory by using the

I CTRL I and 8 keys, and then return to

the first virtual screen to continue with the program. In both cases the previ-

ously displayed screen, normally where the cursor lies, will appear in the real screen area.

2-54

It

is

not

advisable

to

enter a program command

on

the second virtual screen

if

the previous command was executed

on

the first virtual screen.

b) Screen Mode 1 (39 column Split screen text mode)

This screen mode splits the real screen into two halves, each

of

39

columns with

a boundary

of

two characters in the centre

of

the screen. There are two virtual

screens

but

they must

both

have the same number

of

lines. The number

of

lines

in

the virtual screens must be in the range

16

to

48. Only one virtual screen

can be displayed

at

a time. The real screen can be thought

of

as a screen

of

39 columns,

16

lines long which has been split into two blocks

of

eight lines

which are displayed

on

the two halves

of

the real screen. The bottom

of

the

left half

of

the screen

is

continued

on

the

top

of

the right half

of

the screen.

Boundary

I

~

39

columns

+

h L

Virtual screen

window

(left side)

i

l

(Continued on right side)

1------

39

columns

-----<--I

n

Virtual

screen 1

Conditions:

16:5

2n

:5

48

h=7

or

8

n

2-55

39

columns

t

(Continued

from

left

side)

Virtual screen

window

(right side)

39

columns

lines

Virtual screen 2

If

the sequence

of

clearing the screen and printing two directories

of

the C:

drive

is

performed with screen 1 turned

on

(it can be chosen by using the CONFIG program described in Chapter 3), then the screen will show the following output.

I

,~,

XSUB

COM

A}dir

'"

C:

FILINK

COM

TERM

COM

CONFIG

C:

PIP

COM

STAT

COM

SUBMIT

COM

:

XSUB

COM

A>

•

C:

FILINK

COM

TERM

COM

CONFIG .

COM

A>dir

c:

C:

PIP

COM

STAT

COM

SUBMIT

Tracking and non-tracking modes can be set with the SCRN key, and the two virtual screens can be displayed using the

I

CTRL

I and 8 and I

CTRL

I and

EJ

keys just as with screen mode

o.

c)

Screen Mode 2 (the Dual screen mode)

In this screen mode, the real screen

is

divided into two halves. There are two

virtual screens, and each

of

the virtual screens are displayed in the two halves

of

the real screen. While the contents

of

the two screens can be seen at the same

time, they are also independent

of

one another, and so can be scrolled separately.

They canot be set in the tracking and non-tracking mode independently.

The number

of

lines

of

the two virtual screens must be in the range 8

to

48,

and must be the same in both virtual screens. The number

of

columns and the

boundary character can be set by the user. The totalnumber

of

columns must

equal 79, and there must be at least one column in one

of

the screens. The CON-

FIG program described in Chapter 3, can be used

to

set these parameters.

2-56

1

ml

columns

h

lines

1

Screen

window

1

Virtual screen 1

Conditions:

ml

+m2 = 79

h=7

8:sn:s24

n

80

columns

"I

m2

columns

Screen

window

2

t

Boundary

.....

-----

m2

columns

-------l

Virtual screen 2

d) Screen Mode 3 (the graphic screen mode) This mode enables graphics

to

be displayed. Text can also be displayed

on

this

screen. There

is

only one virtual screen whose size

is

the same as the size

of the real screen. Thus scrolling the real screen over the virtual screen and setting the tracking and non-tracking modes do not apply.

2-57

I-

80

columns

8th

lines

Virtual screen

=

Real

screen

Function key display area (optional)

The screen allows individual dots

of

the screen to be lit (bit image mode). This

is

only possible by means

of

software. The most convenient way

to

understand

this mode

is

to use BASIC.

If

this mode

is

used other than in BASIC, it will be with special applications software and the appropriate manual should be consulted for its use.

2-58

Chapter 3

OPERATING THE COMPUTER

UNDER

CP/M

Chapter 2 discussed the operation

of

the computer

at

the simplest level. This

chapter deals with the operation on a day to day level.

It

mainly covers using

the operating system

CP

1M,

housekeeping

of

files and using the utility and ap-

plications programs.

For

a complete guide to the operation

of

an

applications

program,

see

the appropriate manual for that program.

3.1 What

Is

CP/M?

CP

1M

is the most popular operating system for microcomputers. An operat-

ing system

is

a collection

of

computer programs which have been assembled

to

make it easy for the user

to

run programs, handle saving and loading

of

data

and generally allow easy transfer

of

information between software and hard-

ware. The popularity

of

CP

1M

is

due

to

the fact that it can be used

on

a large

number

of

machines.

To understand what an operating system does, consider the analogy

of

a tele-

phone system linked

to

the switchboard

of

a large company.

If

anyone dials

into the company the public telephone network handles the connection

to

the company. The switchboard in the company then directs the caller to the person to

which he wishes

to

speak. Similarly,

if

a person inside the company wishes to callout, he again goes through the switchboard to reach the public telephone system.

CP/M

is

very much like this except that there are a number

of

'switchboards'

for different parts

of

the hardware, e.g. the disk, Microcassette and devices

such as the keyboard and screen.

An"yone

writing software for a

CP

1M

based

machine only has

to

use the equivalent

of

the public telephone system in this

analogy. This means that having written a program such as a word-processor,

it requires little

if

any further programming

to

allow the program

to

be run

on

a computer other

than

the one for which it was originally designed, provid-

ing both computers use the

CP

1M

operating system. All interfaces between the

3-1

software and hardware are handled by the different versions

of

CP

1M

written

for the different computers. This

is

the reason why

CP

1M

has been chosen as

the operating system for the PX-S. The huge library

of

CP

1M

based software

can be installed

on

the PX-S, making it easy for the user

to

find the particular

application he requires. This increases the power and versatility

of

the com-

puter since it

is

only a machine to run software - a tool to extend the mind much

as a hammer

is

a tool to extend the body.

If

you are a beginner to computing,

CP

1M

can be a little frightening. You will

find that the terms used

to

communicate ideas to the computer are not as near

to

normal human communication as one would like. There are a number

of jargon words which will have to be learnt. This chapter has been written in such a way that as far as possible you only have

to

think about the current task.

If

necessary, use the index

to

direct you to the appropriate part

of

the chapter

to

find

out

about anything you do not understand. Any difficulties you

ex-

perience will disappear with practice, and you will find using

CP

1M

will soon

be second nature to you.

The only way

to

learn to use CP

1M

is

to

tryout

the examples given. This manual

cannot hope

to

cover the finer points

of

the system, but fortunately there are

a number

of

books which describe all aspects

of

CP

1M

at

all levels, from the

absolute beginner to the most advanced user. A list

of

some

of

these are given

at

the end

of

Chapter 3.

3-2

3.2 Files And File Names

In a standard CP

1M

system each drive holds floppy disks which are used to store programs. The PX-S has some drives which do not contain floppy disks. For

the purposes

of

using them under

CP

1M,

the RAM disks, Microcassette

drive and the ROM drives behave

as

if

they were standard disk drives. There

are a

few

specific differences, e.g. the ROM drives cannot be used to store in-

formation. The use

of

the Microcassette drive

is

described in Chapter

4.

The programs and data are stored in files. A file

is

simply a collection

of

infor-

mation which

is

related as a unit. Files fall into two main categories. Program

files are a set

of

instructions, for example a wordprocessing program. Data files

store information which

is

used by a program, for example text used by the wordprocessor or the information used by an accounts program. Files are stored by name. To make

it

easier

to

understand which files are which, the name

is

divided into two parts. The first part consists

of

up

to

eight characters which

are used to give a distinctive name

to

the file.

All

of

the printable characters can be used except:

< > , . ; : = ? * [ ] and the space character

The secondary part

of

the name

is

used

to

describe what type

of

file

is

stored.

Secondary names are frequently referred to

as

file types

or

extensions. This part

of

the name

is

used in the MENU

to

select the type

of

file

to

be displayed

on

the MENU in the file name area.

It

is

possible

to

store a file without an exten-

sion but this can cause problems. Applications programs frequently add the

exte~sion

to

the primary name you have given the file so that you know which

files belongs to that program. The extension

is

separated from the primary file-

name by a full stop. Examples

of

file names with extensions are:

BASIC.COM STAT.COM SAMPLE.ASM MEMO.DAT

Note that all filenames are given in upper case letters. Even

if

you type them

in lower case, they are stored

on

the disk

as

upper case.

If

you are using the

filename,

CP

1M

will understand

if

you type the file you want in lower case

or

even a mixture

of

upper and lower case. Note also that the separator in front

of

the extension

is

printed next

to

the primary file name. This may not always

3-3

be so

if

the computer prints

it

out.

Some extensions are standardised and are recognised by

CP

1M

or

particular

programming languages

or

applications languages.

Examples

of

common extensions are:

.ASM .BAK .BAS .COM .DAT .DOC .MSG .OBJ .SUB .TXT .$$$

ASseMbly language source file

BAcKup file BASIC program source file Directly executable COMmand file DATa

file

DOCument file A MeSsaGe file OBject

code for machine code program Command file for use with the SUBMIT program TeXT file Temporary file

Some terms used in this list which are commonly met are:

SOURCE CODE. This

is

text which

is

converted

or

interpreted by a program

to create machine readable codes.

It

is

in a form which

is

understandable provid-

ed you can understand the language it was written in.

OBJECT

CODE. This

is

code directly readable by the computer as a set

of

instructions.

COMMAND

FILE

or

COM FILE. This

is

the most important file you will

meet under the

CP

1M

operating system.

It

is

basically a program file which

is

loaded into memory

to

execute a set

of

instructions. There are a number

of

commands built in to

CP/M.

A COM file

is

sometimes known as a TRAN-

SIENT COMMAND since it

is

temporarily loaded into the TRANSIENT PRO-

GRAM

AREA

or

TPA,

i.e. the

part

of

the computer's memory set aside to

run

programs.

3.2.1 Referring to file names (ambiguous/unambiguous file names and wildcards)

In

many cases

CP

1M

or

a program requires you to use the complete, exact file

name.

In

this case there

is

no

doubt

which file

is

being referred to. The name

is

UNAMBIGUOUS as there

is

only one file

of

that

name. Sometimes you may

3-4

wish

to

refer

to

several similar file names.

For

example they may be all the files

beginning with the letter

"E"

or

all the files with

extension"

.COM".

In

this

case the file name

is

AMBIGUOUS.

In

references

to

CP

1M

you will frequently

see these terms abbreviated:

ufn afn

means means

Unambiguous File Name Ambiguous File Name

In

using ambiguous file names, you need

to

tell

CP

1M

some further informa-

tion, so

that

it can have a precise idea what you mean.

In

order to do this you

can use the

"?"

characters to denote

"any

character"

and

the"

*"

to

denote

"any

group

of

characters". The

"?"

and"

*"

characters are known as WILD-

CARD characters.

For

example:

*.COM

NAME. *

Warning:

means any file name with the extension .COM means all the files with the primary name

"NAME"

but

with any extension,

ego

NAME.COM, NAME.BAS, NAME.DAT means any file name beginning with E which has the extension .COM means all files beginning with E no matter what their extension

you

cannot use:

*P.

* to mean all the files ending

in

the letter

"P".

CPIMwill

treat this

as meaning every single file. This is important to remember

if

you

are

erasing files from a disk.

????????

.COM

????COM

A???*

?S???BAS

?????ROP.*

*.B??

means any file with the extension

.COM

because there are eight (i.e. the maximum) wildcard characters. means any file

of

not more

than

four characters in length, which has the extension .COM. means any file beginning with the letter

"A"

which has

not

more

than

four characters.

means any file whose second character

is

"S",

which

has five

or

less characters, and has the .BAS extension.

means any file ending in the characters

"ROP".

means all files whose extensions begin with the charac-

ter

"B".

3-5

3.3 Starting To Use

CP

1M

Although the MENU

is

an aid to using

CP

1M,

it

is

not a replacement.

To

use

the MENU effectively, a working knowledge

of

CP/M

is

required.

An

under-

standing

of

how to use

CP

1M

is

also required to make effective use

of

the

CP

1M

utility programs.

3.3.1 Disk drive names

Switch

off

the MENU from the System Display (section 2.2.3) and the screen

will clear to show the system

prompt

"A>".

All drives are given

an

identifica-

tion letter.

It

is

possible

to

change the relationship between the actual physical

drives and the identifying letter on some

of

the drives. This can be done with the CONFIG program described in section 3.8. When you initialize your PX-8 the drives are specified as follows:

Identifying letter

A:

B:

C:

D:

E:

F:

G:

H:

Physical Drive RAM disk ROM 1 ROM 2 Floppy Disk Drive 1 Floppy Disk Drive 2 Floppy Disk Drive 3 Floppy Disk Drive 4 MICROCASSETTE DRIVE

The default drive

is

set

to

drive A: which

is

why the system prompt said

"A>".

Notice

that

apart

from the system

prompt

the drive name

is

followed by a col-

on(:). Since file names and commands consist ofletters,

CP/M

has

to

have some

means

of

recognising when you are talking about a disk drive identifier. The

colon

is

always used in

CP

1M

to denote a drive. The system

prompt

always

includes the default

or

currently "logged

in"

drive as a reminder

to

you which

drive

is

currently logged in. Unless you specify another drive, all access to drives

(saving and loading

or

simply inspecting the contents

of

the drive) will be made

to

that

drive. To use the currently logged in drive, you need not type in its iden-

tifier. This can be seen with the following sequence

of

operations:

Type the command DIR next to the system prompt and press the

I

RETURN

I key.

This means

"show

me all the files stored on the currently logged in drive".

If

there are no files on the disk the screen will show:

3-6

A)DIR NO

FILE

A)

You can specify another drive by adding the drive name after the

DIR

com-

mand as follows when the screen will show:

A)DIR c: C:

PIP

COM : STAT

C: FILINK COM:

TERM

A)

COM

SUBMIT

COM:

XSUB

COM

CONFIG

COM

Rather

than

type the command DIR, you can press the Programmable Func-

tion Key

I

PF1

I . This will print the command

"dir

" , including the required

space.

To

change the logged in drive, type the name

of

the new drive and press the

I

RETURN

I key.

For

example

to

change the logged in drive

to

drive C: type the

two characters

"C:"

and press I

RETURN

I . The

prompt

then changes to

"C>".

Now simply using the

DIR

command will give a directory

of

drive C:,

and

then

return to show drive C:

is

the currently logged in drive.

If

you do this the screen

will show:

A)C: C)DIR C:

PIP

COM : STAT

C: FILINK COM:

TERM

C)

COM : SUBMIT

COM:

XSUB

COM : ·CONF

I G

COM

3-7

COM

Drive name can be used in combination with the file name described in section

3.2

as

follows.

x:

xxxxxxx.xxx

LJ

\ I

L--.J

Drive Primary file type

name file name (extension)

'w",,"·

B:

BASIC. COM

or

A: SAMPLE.BAS

3.3.2 Changing disks, tapes and ROMs - warm starts

On a conventional

CP

1M

system the disks in the drives could, and indeed would

be changed regularly.

If

you have additional disk drives you will experience the

same problems as

on

a conventional

CP

1M

system

if

you do not change the disks in a correct manner. On the PX-8, unless you have additional floppy disk drives, only Microcassette tapes and ROMs will be changed.

It

is

more impor-

tant

to

obey the rules in changing tapes, as data you have saved may not be

readable

at

all unless you remove the tape in the correct manner.

When you change disks, you must let

CPIM

know you have done so. This

is

because certain disk directory information

is

stored in memory

at

all times, which

is

used to allocate space

on

the disk. When a disk

is

changed, this information

must be replaced by the information from the new disk.

If

you change a disk

without telling

CP

1M

you have done so, it

is

possible

to

lose data from the

new disk, and also files may not be closed properly

on

the old disk making

it difficult

to

read them.

IF YOU CHANGE FLOPPY DISKS always press

1 CTRL

1-

[g

or the 1

SlOP

1 key

after you have done so.

ALWAYS EXIT A PROGRAM IN AN ORDERLY MANNER by taking the EXIT option.

In

some cases there will be a specific command to do so, in others

you can use

1

CTRL

1 - @ .

3-8

A WARM START restores the internal information which

CPIM

uses to re-

orientate itself. This

is

normally when disks have been changed

or

you have

exited from a program.

If

the MENU

is

switched on, and you exit from a pro-

gram

if

it does a warm start, the MENU will be displayed.

If

a program leaves

the

CP

1M

prompt

on

display and the MENU

is

switched on you should carry

out

a warm start by pressing 1 CTRL 1 -

[g

or

the 1

SlOP

Ikey.

There may be a

reason for the

CP

1M

command line being displayed, most probably because

there

is

information to be read from the screen which would disappear before

you could read it,

if

the MENU came up straight away.

3.3.3 Changing ROMs

Details

of

physically changing over ROMs are given in Chapter 4. Since ROMs behave like write protected disks, when changing ROMs you must also carry out a warm start.

3.3.4 Changing microcassette tapes

The Microcassette drive has been designed to operate as a disk drive. However, because it

is

physically different it cannot be treated quite the same.

It

should become a habit to change a Microcassette tape through the System Display. Otherwise it

is

possible

to

not only make the removed tape unreadable, but also

the one onto which you are writing the new data. Full details

of

using the

Microcassette Drive are given in Chapter 4.

WARNING:

A Warm start does

not

update the directory on a Microcassette tape.

Al-

ways change tapes through the System Display. This can be done in the

middle

of

an applications program

by

pressing 1

CTRL

1 and the 1 HELP 1 key.

On completing any changes via the System Display, control will be returned to the applications program

at

the

point

where

you

left

off

3-9

3.4 Using The Keyboard Under

CP/M

Since

CP

1M

has been designed as a universal operating system, it does not neces-

sarily allow all the special keys

on

the PX-8

to

function as they do in BASIC

or

in some applications programs. In particular the cursor keys are

not

sup-

ported by

CP/M.

Some

of

the special keys behave differently. The following

summarises the use

of

the different functions available form the keyboard when

the PX-8

is

on

the

CP

1M

command line. They do not hold for the MENU com-

mand line.

3.4.1 Using the programmable function keys

The keys ~ to

I PF5 I and their shifted counterparts can be used

to

print the

common

CP

1M

command words, thus preventing errors and saving time. When

setting them up, it

is

worth ensuring

that

trailing spaces are included

to

con-

form with the requirements

of

CP

1M.

The key display

is

normally absent from

the lowest line

of

the screen

but

can be switched on using the CONFIG pro-

gram. Another alternative in deciding which key provides which string

is

to

use the attached Programmable Function key label. The CONFIG program also allows alteration

of

the strings given by each key.

3.4.2 Line termination commands

When you have entered a command, you must tell

CP

1M

that you have finished.

There are three key commands to do this:

The

I

RETURN

I key

is

the simplest way

to

enter a command.

A

I

CTRL

I -

[MJ

is

equivalent to a pressing the I

RETURN

I key.

A

I

CTRL

I -

QJ

is

equivalent to a line feed.

On

the

CP

1M

command line it

also causes the command to be entered as though you had pressed the

I

RETURN

I

key.

3.4.3 Character deletion commands

If

a mistake

is

made, it

is

necessary to correct it. This can be done in two ways,

but

the CURSOR KEYS CANNOT BE USED.

I

CTRL

I -

[Hl

or the

BS

(backspace) characters delete the character

to

the left

of

the cursor from the screen and move the cursor one step back.

The

[QKJkey

causes the key

to

the left

of

the cursor to be deleted,

but

also

repeats the deleted character on the screen.

lethe ~ or I

CTRL

I -

[Hl

is

used

3-10

to delete another character it will place the cursor one place

to

the left

of

this

deleted character because any characters deleted by

the[QKJkey

do not exist

except

on

the screen.

3.4.4 Line deletion commands

Sometimes it

is

necessary to delete a whole line when a mistake

is

made or for

other reasons. There are two ways

to

do this:

00

will backspace

to

the beginning

of

the line, erasing all

of

the text.

I

CTRL

I -

[Q]

will place a " # " character

at

the end

of

the line and then place

the cursor

on

the next line ready

to

start over again. This

is

useful, because

the incorrect command

is

still present on the screen, although it has been erased.

3.4.5 Display control commands

There are a number

of

control key sequences which can be used to handle the screen display. Again not all the special keys work, although some can be made to

perform their function to a limited extent.

The

I

CLR

I key can be used to clear the screen, although it

is

not supported by

CP/M.

It

is

equivalent to a I

CTRL

I -

UJ

. Typing either

of

these commands

causes the

CP

1M

command line to show:

Pressing the

I

RETURN

I key will clear the screen, printing a question mark in the

top

left hand corner. The system prompt will be placed

on

the third line. This

is

because

if

you give

CP

1M

a command it does

not

understand it will repeat

the command followed by a question mark and return the system prompt.

I

CTRL

\ -

[f]

can be used

to

overflow on

to

the next line before the user has

pressed the

I

RETURN

\ key. This

is

useful

if

the screen

is

split (screen mode 1

or

2), as it enables a new word

to

be written

on

to

a new line so

that

it can

be read more easily.

The"

#"

character

is

placed

at

the end

of

a

l~ne

when

using the \

CTRL

\ -

[Q]

or

I

CTRL

\ -

[BJ

command to show it

is

a terminated

line, to distinguish it from a

1

CTRL

\ -

[f]

.

I

CTRL

\ -

[BJ

is

used to repeat a line with the errors removed

if

you are a bad

typist and using the

I

DEL

I key frequently. For example

if

you type an

"R"

in-

stead

of a "T"

in the

"STAT"

command, and ha(Cdeleted the

"R"

using DEL,

and

pressed I

CTRL

\-

[BJ

keys after typing

"T"

again the screen would show:

3-11

A>

STARRT

#

STAT

The

~

key performs the same function as I

CTRL

I -

[BJ

.

The I

PAUSE

I

or

I

CTRL

1-

~

key can be used

to

temporarily halt the screen scroll-

ing.

For

example

if

a DIRectory has

too

many

files

to

fit in the screen window,

pressing either the I

PAUSE

lor

I

CTRL

I -

~

keys will stop the display until another

key

is

pressed, enabling the text

to

be

read. The shifted cursor keys can also

help with this problem as described below.

The

SHIFTED

CURSOR KEYS (

[!]

and

[IJ ) can be used

to

scroll the

real screen window

up

and

down the virtual screen. Thus

if

a long DIRectory

has scrolled

off

the real screen, these keys

can

be used

to

bring it

on

again.

The I

CTRL

I

and

CURSOR KEYS ( G

and

@ ) can be used

to

change

the

displayed virtual screen in modes 0

and 1 and

the

cursor position in screen

mode 2.

For

example a DIRectory can be stored

on

one virtual screen while

a program

is

used

on

another. Care must

be

taken

in using this facility. Full

details are given in section 2.2.6.

The! SCRN

!key

can

be

used

to

lock

the

real screen window

on

part

of

the

virtual

screen. This is described in section 2.2.6.

3.5 Printing When

On

The

CP

1M

Command Line

There are two ways

to

print when

on

the

CP

1M

command

line.

The !

CTRL

I

and

!

PF5

! key can be used

to

dump

the contents

of

the

screen

to

the

printer.

I

CTRL

I -

~

can

be

used

to

toggle the echoing

of

text

to

the printer. The first

time !

CTRL

I -

~

is

pressed anything

output

to

the screen

is

simultaneously

sent

to

the printer. Pressing ! CTR!,] -

~

a second time only sends input

to

the screen. This can be used in utility programs, but may

not

work in applica-

tions programs.

3-12

e ,

,...

~

...""

C;,

.~

~)

.~

C;,

..

~

,

3.6 The Concept

of

Logical

And

Physical Devices

As a universal operating system,

CP

1M

has

to

have a means

of

communicating

with all

the

devices associated with a computer in a general way. The software

in

each computer

is

then

connected

to

the devices which are unique

to

that

par-

ticular computer. This is achieved through the use

of

the concept

of

logical (sym-

bolic) device names in

CP

1M

being assigned

to

physical (actual) devices

supported by

the

computer. Such a concept considerably simplifies the use

of

the

computer.

NOTE: In practice assignments are carried out by the use

of

the CONFIG program

described

in

section 3.8. This allows various devices to be assigned using com-

mon names, rather than following the normal

CPIM

system. The description

outlined below

is presen

tedfor

completeness,

andfor

thosefamiliar with CPIM,

who

wish

to use the

STAT

program (section 3.8) to change assignments.

3.6.1 The logical devices

There are four logical devices in

CP

1M

which correspond

to

the types

of

devices which one would expect with a computer. They are given the symbols CON:, RDR:,

PUN:,

and

LST: from the names associated with their functions.

CON:

denotes the CONsole device, which

is

the means

of

allowing

data

to

be

input

by

and

output

to

the

user.

In

the case

of

the

PX-8 it would correspond

to

the keyboard

and

LCD

screen.

RDR: denotes

the

ReaDeR device, which receives information from another

source. The name originally derives from a paper tape reader,

but

in the PX-8

is

normally the RS-232C device.

PUN:

denotes a device

to

output

information. Its name derives from a paper

tape

PUNch.

In

the

PX-8 it is normally assigned

to

the RS-232C port.

I,s1': denotes the

output

LiST device, normally a printer.

3-13

3.6.2 The physical devices

There are many possible physical devices which can be attached to a computer. Examples

of

such devices are printers, plotters, modems, and video monitors.

They all have one thing in common, they involve the transfer

of

information

to

or from the computer. The physical devices are given symbols in

CP

1M

which

like the logical symbols relate

to

their function. A computer manufacturer may

not

support each device, and different manufacturers may give different assignments to the same device. The symbols corresponding to the physical devices are:

TTY: denotes a slow speed terminal. Its name

is

derived from the

TeleTYpewriter, which has a keyboard

and

printer as input and output devices

for the user

to

communicate with the computer.

CRT: represents a high speed console device. Its name

is

derived from the

commonest type

of

device a Cathode Ray Tube.

BAT: denotes a BATch processing device, which historically relates to devices such as punched card readers.

UCI:

denotes a User defined Console device, which allows special console

equipment

to

be used.

PTR:

corresponds

to

a Paper Tape Reader.

.

URI:

and UR2: correspond to two different User defined Reader devices. They

enable a computer manufacturer

to

provide two different high speed devices

for input

of

data.

PTP:

denotes a Paper Tape Punch device for output

of

data

to paper-punch

equipment.

UPI:

and UP2: correspond to two different User defined Punch devices. They

enable a computer manufacturer to output data

to

two high speed output devices.

LPT:

is

a Line PrinTer which allows data

to

be printed for a permanent record.

ULI:

is

a User defined List device.

It

enables the computer manufacturer to

provide

an

interface for communication

to

special devices such as plotters.

3-14

3.6.3 Physical Devices Supported by the PX-8

The PX-8 does not have all the physical devices which could be supported by CP

1M.

The physical devices which the PX-8 has are:

1)

The LCD display.

2)

The keyboard

3)

High speed serial port, which

is

used to communicate with floppy disk drives,

printers and other special devices.

4)

RS-232 serial port, which

is

used to communicate with other computers and

also printers.

A computer manufacturer has

to

modify

CP

1M

so

that

a particular physical

device corresponds

to

one

or

more

of

the names allowed by

CP/M.

A device

can correspond to more than one name, and each

of

the logical devices can

be connected to more

than

one physical device. The four logical devices can

be assigned

to

the physical devices as follows:

Table 3.1

Logical Device

1/0

Physical Device

LST:

TTY: CRT: LPT:

ULI

0

Serial (printer) LCD display

RS-232C not implemented

PUN: TTY:

PTP

UPI:

UP2:

0

not implemented LCD display RS-232C

not implemented

RDR: TTY: PTR:

URI:

UR2:

I keyboard not implemented RS-232C

not implemented

CON: TTY CRT: BAT:

UCI:

output

0 RS-232C LCD RS-232C

RS-232C

input

I keyboard keyboard

RS-232C RS-232C

3-15

3.7 The

CP/M

Built-In Commands

Built-in commands are commands which can be executed simply by typing in their name on the command line. They do

not

show

up

as files

on

the directory

(as do STAT and

PIP,

for example)

but

are

part

of

CP/M

itself. They are:

DIR

ERA

REN

SAVE TYPE USER

Display a list

of

files

on

a particular disk.

Erase a specified file

or

files. Rename a specified file. Save a portion

of

memory as a file.

Display the contents

of

a file

on

the screen.

Assign files

to

different users

3-16

3.7.1 D

IR

(Directory)

This command

is

used to display a list

of

file names stored

on

a disk. There

are various ways

of

specifying the files depending

on

the results you want. These

are achieved using wildcards (section 3.2.1).

On

a conventional

CP/M

com-

puter the

CP/M

operating system

is

loaded into the computer from disk.

It

is not displayed

on

the directory.

It

is

also possible

to

make other files non-

directory files. This can be done in two ways. Files can be set (and reset)

to

'SYS' files using the STAT program. These files do

not

appear

on

the directo-

ry

of

any user. Files can also be assigned

to

different users using the USER

command, and then only appear

on

the directory when the particular user to

which they belong

is

using the disk.

Points worth bearing

in

mind when using the

DIR

command are:

• There must be a space between DIR and the filename (if there

is

one).

• No space must be

put

between the drive name

and

filename

if

this

is

used.

• The files are

not

sorted into alphabetical order, and are usually displayed

in the order in which they were first put

on

to the disk.

If

you require

an

alphabetical list it

i~

best

to

use the STAT command.

a) List all files

on

the currently logged-in drive

The simplest way

to

do this

is

to

type DIR

on

the command line:

C>DIR C :

PIP

COM:

STAT

COM:

SUBMIT

COM:

XSUB COM

C : CONFIG

COM:

FlUNK

COM:

TERM

COM

The same result can be obtained by being more long-winded and using the drivename or wildcards:

C>DIR

C:

C >

DIR

C:???????? *

b) List all the files

on

a drive

oth~r

than

that

currently logged

in

This can be done simply by adding the required drivename to the command:

C>DIR

A:

PIP

COM

3-17

C>DIR

B:

BASIC

COM

c)

List all the files with the same extension

on

any drive

Wildcards can be very useful when this

is

required. For example, to show all

the COM files

on

the current drive:

C>DIR

*.COM

C : PIP

COM:

STAT

COM:

SUBMIT

COM:

XSUB COM

C : CONFIG

COM:

FlUNK

COM:

TERM

COM

C>DIR

A: * .BAS

NO

FILE

This message informs you

that

there are

no

files conforming to

that

name

on

the

A:·

drive. The message will appear whenever you ask for a DIRectory

of

a drive

on

which no files with the specified name reside.

C>DIR

D:*.BAS

D : TEST

BAS:

DEMOl

BAS:

DEM02

BAS

There may be other files

on

drive D:

but

as the request was only for those with

the extension BAS so they are the only ones listed.

d) Check

that

a particular file is

on

a particular drive

If

you ask for a particular file by name it

wi~l

be displayed

on

the screen.

If

it

is

not

present the

"NO

FILE"

message

wIll

be prmted.

For example:

A>DIR

B:TEXTl.DAT

A>

shows the file

is

on disk B :

A>DIR

B:TEXTl.DAT

NO

FILE

A>

shows the file

is

not present.

3-18

e)

List all the files with the same name

on

any drive

It

may be that there are files with the same name but different extensions on the same drive, for instance assembler program files, so the asterisk wildcard can again be used:

D>DIR

START. *

D:

START

ASM:

START

HEX:

START

PRN

C>DIR

D:START.*

D:

START

ASM:

START

HEX:

START

PRN

f)

List all files with similar names

on

any drive

This

is

where you can really start to use the wildcards!

For

instance:

D>DIR

S??????? *

will list all files on drive D: whose names begin with S

of

any extension;

D>DIR

C:

* .cn

will list all the files on drive C: whose extension begins with C;

A>DIR

D:DEM??BAS

will list all those files on drive D: whose names consist

of

five letters beginning

with DEM and whose extensions are BAS.

g)

Microcassette Tape DIRectories

The Microcassette drive

is

always named drive H: and

is

used in the same way

as the other drives.

H>DIR H:

TEST.BAS

If

the tape

is

mounted, the directory will be read from the directory stored in

memory, and so will be read immediately.

(

If

the drive

is

unmounted when an access

is

made the drive will wind the tape

to the beginning and mount the tape. The directory

is

then stored in memory.

It

may take a short while for the tape to be mounted.

3-19

It

is

better

to

keep to the habit

of

mounting and removing the tape through the System Display. Before carrying out a directory operation on the Microcassette drive, use the System Display

to

check

if

the tape

is

mounted.

If

it

is

not

mounted, mount it through the System Display.

WARNING: NEVER

try to obtain the directory

of

a Microcassette tape when another

tape is already mounted. The directory

of

the second tape must be loaded into memory before the directory can be printed. This can only be done by

removing the first tape and then mounting the second tape.

h) Pausing a DIRectory Either the

I

PAuSElkey

or I

CTRL

I-[§]

can be used to pause a DIRectory as it

is

displayed.

If

a directory has scrolled

off

the screen in screen modes 0,1 or

2,

it

can be seen by using the shift cursor keys ( [!] and m

).

i)

Printing a DIRectory

To obtain a hardcopy

of

a DIRectory, use I

CTRL

I -

~

before issuing the DIR

command or use the screen dump facility (

I

CTRL

I and the I PF5 I key).

j)

Stopping the DIR

If

any key

is

pressed during execution

of

this command it

is

terminated and

the

CP/M

command line reappears.

3-20

3.7.2

ERA

(Erasing files)

Files can be erased

at

any time using the ERA command. The command

is

used

in a similar way

to

the DIR command and the rules about spaces apply equally.

It

is possible to set files

to

be Read/Only files. Files which have been set to

Read/Only cannot be erased.

If

you really do want to erase them you can use

the STAT program

to

set them to Read/Write.

In

fact ERA does not really

erase the file from the disk - it simply removes the directory entry for it.

Files

on

the ROM drives cannot be erased.

If

an

attempt

is

made to erase a

file

on

a drive which

is

set

to

Read/Only, one

of

the following error messages

will be displayed:

BDOS ERROR ON dr:FILE

R/O

BDOS ERROR ON

dr:R/O

will occur. The particular drive name

"dr:"

will be printed as the drive name

accessed.

If

this does occur you should press I

CTRL

I -

(g

, I

STOP

lor I

RETURN

I .

a) Erase a specific file on any drive To

do this you simply specify the full filename and extension

of

the file you

wish

to

erase:

D > ERA TESTING. COM D>

C > ERA A:WASTE.FIL C>

If

the file

is

not present the

"NO

FILE"

message will be printed.

C>

ERA DUDFILE.COM

NO FILE

C>

\

3-21

/"-

WARNING:

W USING WILDCARDS

WITH

THE

ERA

COMMAND

It

is very easy to erase files

you

do not wish to erase from a drive by using wild-

cards with the

ERA

command.

TO A VOID

ACCIDENTS

use the

DIR

command with the same wildcard option you wish to use. The files displayed by the DIRectory will then be the ones ERAsed. This will ensure that you know what

your

action will be without caus-

ing anything drastic to happen.

IF

YOU

ARE

USING

'SYS'

FILES these will be deleted by the

ERA

command,

even though

you

did

not

see them on the directory. To avoid accidents use the

STATprogram to check the complete list

offile

names

if

you

are

using

'SYS'

files.

Alternatively delete files one

at

a time.

b) Erase all files

on

a drive

This

is

achieved by using the asterisk wildcard. Since this

is

drastic action, it

results in a question from the PX-8 asking

if

you are sure you want

to

erase

all the files:

A>ERA

*.*

ALL

(YIN)?

If

you answer N execution will be terminated, and answering Y will result in

all the files in the directory being ERAsed. Any files NOT in the directory

will

not be erased, that

is

system files and those with the

SYS

attribute set.

To erase all files

on

another drive the drivename must be specified:

C>ERA

D:*.*

ALL

(YIN)?

c)

Erase all files with the same filename

on

any drive

The asterisk wildcard can be used

to

erase all the files on a particular drive,

which have the same name but whose extensions differ.

D>ERA

START. *

will erase all those files

on

drive D: whose filename

is

START and whose

ex-

tension

is

anything, for instance, START.ASM, START.BAS or START.DAT.

C>ERA

D:START.*

3-22

will have exactly the same effect but

is

executed when C:

is

the logged-in drive

instead

of

D:.

d) Erase all files with the same extension on any drive To do this you must specify the extension in full but use the asterisk wildcard

to allow any filename:

C>ERA

*.COM

will erase all the files on drive C: having the extension COM.

C>ERA

D:*.BAS

will erase all files

on

drive D: with the extension BAS, that is, all BASIC pro-

gram files.

e)

Erase all files with similar names

or

extensions

on

any drive \ Here you can use both the asterisk and the question mark wildcards. The asterisk replaces

an

entire filename or extension and the question mark replaces in-

dividual characters in the filename or extension:

C>ERA

S?????*

will erase all files

on

drive C: with any extension and whose filename consists

of

six characters beginning with

S.

C>ERA

D:TES?????BAS

will erase all those files

on

drive D: whose extension

is

BAS and whose file-

name begins with TES.

D>ERA

A:DEMO????A

will erase all files

on

drive A: whose filename consists

of

six letters beginning

with DEMO and whose extension ends in A.

f)

Erasing Files on a Microcassette drive.

On a conventional drive when a file

is

removed from the directory, the disk is opened up for saving other files. On a Microcassette tape the files are saved sequentially as a single block. This means that the removing a series

of

files

from a tape directory does not free up the tape.

It

will

simply removes the name

3-23

from the directory.

If

the space were freed, it would be possible for a new file

to

overwrite the start

of

a current file.

If

the file

is

the last file

on

the tape,

the file space will be set free for further use.

To remove a block

of

files from the middle

of

a tape, and free the tape for

new files,

o Use the

PIP

program

to

transfer the files

at

the end

of

the tape into the

RAM disk.

o ERAse all files from the block you want

to

delete

to

the end.

o Use the

PIP

program

to

replace the end files back

on

the tape.

WARNING:

The directory is only updated in memory when disk access is carried

out. Only when the tape is removed will the directory be written to

tape.

It

is

especially important to remove a tape using the correct

procedure

if

the

ERA

command has been used on a Microcassette

tape.

3-24

3.7.3

REN

(Rename a

file)

Ii,IIII@"

REN new filename = old filename

A file can be renamed at any time by giving this command followed by the new

filename, an equals sign and the old filename. There must be a space between REN and the new filename. although it

is

optional either side

of

the equals sign.

A>REN

NEW.COM = OLD.COM

A>

has changed the filename

"OLD.COM"

to

"NEW.COM".

If

the new filename you have chosen already exists

on

that drive, the message

FILE EXISTS

is

displayed and the comIhand line reappears:

A>

REN TESTING.BAS = DEMO.BAS

FILE EXISTS

This indicates that there

is

already a file

on

drive A: called TESTING.BAS.

This can also happen

if

you specify the names the wrong way round, since a

test

is

carried out

on

the new name before carrying

out

the renaming.

If

a drive name

is

specified it must be placed before new filename:

C>REN

A:START.COM = TESTING. COM

This example will have the result

of

renaming a file

on

drive A: called TEST-

ING.COM to be called START.COM.

Bear in mind that this command only renames the file, so the old filename disappears from the directory and is replaced by the new name while the file itself remains exactly the same. Another important thing

to

remember

is

"that

you

can only rename files

on

one drive, . for example:

C>

REN A:DEMO.COM = B:TESTING.COM

is

not allowed and will result in the message:

B:TESTING.COM?

3-25

~

If

you want

to

copy a file from one drive to another and rename it at the same

time use the

PIP

program.

3-26

3.7.4

SAVE

(Save

an

area

of

memory)

First

of

all, remember

that

this

is

completely different to the SAVE command

in BASIC. The only feature they have in common

is

that

they store programs

on

disk,

but

there the resemblance ends.

It

enables blocks

of

memory to be

saved as a file

on

a disk. Normally only programmers will use this command,

but

there

is

one case where

it

may be useful

to

even BASIC programmers which

is

described below.

The format for the SAVE command

is

very simple.

SAVE n filename

The filename consists

of

a drivename (if necessary), filename and extension,

in the usual way. The

'n'

parameter denotes the number

of

"memory

pages" to be saved and

must have a space either side

of

it. The value

is

specified in decimal notation.

One page consists

of

256 bytes

of

data, so the basic method

of

calculating n

is

to

divide the number

of

bytes you want to save by 256

and

round the answer

up

to

the next integer.

For

instance,

if

you want

to

save 300 bytes the number

of

pages (n) would be 2 because 300 divided by 256

is

greater than)1lle but less

than

two.

A frequent use

of

SAVE

is

to write

to

disk a program which has been patched

using the

DDT

program (see section 3.10). When the program

is

loaded with

DDT

the address

of

the next available byte

is

shown as NEXT. You can calcu-

late the number

of

pages

to

SAVE in the following way:

1)

Round the value shown as

to

the next highest page. Taking as

an

example

if

2C5A were returned by NEXT in DDT, this would give

2DOO

(remembering

that

you are working in hexadecimal notation).

2)

Drop the zeros from the end

of

the rounded value

and

calculate the value

of

the remaining digits in decimal.

In

the example 2D becomes

45

decimal.

3)

Since

DDT

loads programs

at

the beginning

of

the first page

of

memory,

subtract 1

to

allow for this, giving 44 in the example.

If

the file

we

have just patched

is

called FREDDY.COM and lives

on

the D:drive,

the command given

to

write it back to disk will be

C>SAVE

44 D:FREDDY.COM

3-27

a) The

"SAVE 9 GO.COM"

Trick

There

is

a special trick you can play

on

the PX-8 using the SAVE command which can be very helpful in various circumstances. When you exit a program it

is

still present in memory.

For

example when exiting BASIC using the 'system' command, the BASIC interpreter and the programs in the five program areas are still existant in memory as far

as

MENU

is

on. You may then remem-

ber that one

of

the programs should have been saved, and will be lost

if

you

try

t~

restart BASIC.

Als~

you

~ight

load a program such as

PIP,

then having

used

It

once to transfer a smgle

fIle

done nothing except a DIR or ERA or other

minor operation, and then wish

to

use it again. In either case the program (the

BASIC interpreter,

PIP

or whatever) can be recalled instantly

if

you know how

instead

of

having

to

be reloaded from disk

or

even tape. In the case

of

BASIC

the five programs stored in memory can be recovered just

as

if

you had not

exited

to

CP/M.

First you have

to

create a file called GO.COM then execute it when you wish to continue with the previous program by typing GO. To create this file all you have to do

is

type:

A>

SAVE 9 GO.COM

or

A>SAVE

9 D:GO.COM

If

you want it on the D: drive, for instance. what you are actually doing with

this command

is

making a file

of

length 0 bytes and saving it on the specified

drive. When you type GO

at

the prompt the program GO.COM (of length 0

bytes)

is

loaded into memory and executed. Because the file contains 0 bytes it does not overwrite the program already in memory, so in fact the program already there

is

executed instead.

3-28

3.7.5

TYPE

(Displaying the contents

of

a file)

".UIIF"

TYPE filename

This command

is

used

to

display a file on the screen. There must be a space

between TYPE and the filename. This

is

usually an ASCII file because any other

data format results in a screenful

of

rubbish and

is

totally incomprehensible.

This

is

because as the computer reads through the file it tries to convert all the

hexadecimal numbers it finds into printable ASCII characters, and the only

files which produce anything recognisable are those which are in ASCII format. For example,if you wanted

to

look

at

a BASIC program file using TYPE, it would

have

to

have been SAVEd in ASCII format using

the"

,A"

option in BASIC.

Normally, BASIC programs are stored in compressed binary format which

will

produce some very strange results

if

it

is

TYPEd

to

the screen.

a) Displaying the contents

of

a file'to the screen

The command

is

invoked either

to

show the contents

of

a file from the current

drive:

A>

TYPE TEXT .TXT

or

for example:

C>TYPE

D:DATAFILE.DOC

will display the contents

ofthe

file DATAFILE.DOC which

is

held

on

drive D:.

The only files which you can be sure will contain data in ASCII format are those with the extensions ASM,

PRN

and DOC or TXT. Others may be in this

format, and it doesn't do any harm to look

at

them anyway

if

you want

to

in order to check. WILDCARDS cannot be used with the TYPE command.

If

the file

is

not

on

the disk the filename will be repeated

on

the next line with

a question mark after it, for example:

C>TYPE

B:TEXTl.DOC

B:TEXTl.DOC?

This would also happen

if

an

attempt was made to use wildcard characters.

3-29

)

b) Pausing the display

of

a text file.

When the text

is

displayed

on

the screen, it may be going to fast to be read.

You can pause the display by pressing the

I

PAUSE

I

or

I

CTRL

I -

~

key.

If

you

wish to see some

of

the text which has scrolled out

of

the real screen window,

but

is

still present on the virtual screen, the shifted cursor

keys

(

[!]

and [±] ) can be used when the display has been paused. To continue the display press any key other than the shifted cursor keys.

c)

Stopping the Display

Pressing any key other

than

the I

PAUSE

I , I

CTRL

I -

~

or

a shifted cursor key

will cause the TYPE command to cease displaying the file. The PX-8 will then

return to show the

CP

1M

prompt.

d) Printing a File using TYPE.

It

is

possible

to

echo the file to the printer by typing I

CTRL

I -

~

before in-

voking the TYPE command, and so produce a hard copy

of

the text.

Small passages (i.e.

of

screen size) can be printed using the screen dump, by

pressing

I

CTRL

I

and

the I

PF5

I key.

e)

Problems with

TYPE

using non ASCII files.

If

an attempt

is

made

to

view a non text file, the screen may be covered with

a garble

of

non

displayable characters. When stopped, the

CP

1M

prompt may

not

appear. In this case you will have

to

press the reset button, and in extreme

cases initialize the system.

See

section 2.1.3

if

this occurs.

3-30

3.7.6

USE

R (selecting a different user areas)

u.n@"

USER n

If

more than one person will be using the PX-8 it

is

a good idea to give each

a user number. This has the effect

of

dividing the drives into different areas,

each

of

which contains files belonging to a different user. Thus two users may

label their areas 0

and

1,

and they can both have files with the same names

because their numbers are 'invisibly' added

to

the filenames in their respective

directories. When the PX-8

is

switched on it defaults

to

user area 0, that is,

it assumes you are user number 0 unless you tell it otherwise.

If

you are user

number 2, simply give the command

C>USER

2

and

you will have immediate access to your own files. There must be a space

between USER and the area number.

If

you want to look

at

a file in another user area you can either give the USER command again with the relevant number, or use the

PIP

program using the [G) option.

To

find

out

which user numbers are active

on

a particular disk, use the STAT

program.

3-31

3.8 Using Utilities and Application Program with

CP

1M

Computers are normally used to run applications programs, for example to write text using a word processor. These programs are loaded from the disk into the memory

of

the computer when they are needed.

For

this reason they are often

called transient commands

to

contrast them with the built-in commands. Such

programs are given the file extension .COM meaning a command type

of

file.

They are executed by typing the name

of

the file without the extension as

if

they were a command. For example

to

use the file TERM. COM which

is

a pro-

gram

to

use the PX-8 as a terminal, you would simply type the word TERM

after the

CP

1M

prompt.

3.8.1 Utilities

The PX-8

is

provided with a ROM which contains a number

of

programs which

are used for common day

to

day management

of

the computer, for example

transfering

files

and changing parameters. They perform the following functions:

PIP

is

a program for copying files.

STAT

is

a program to determine the status

of

the disks and perform general

housekeeping functions.

SUBMIT

is

used

to

process a sequence

of

commands.

XSUB

is

used

to

allow input from the keyboard with SUBMIT.

CONFIG

is

used to change system parameters which are not changed often.

TERM

is

a program

to

allow the use

of

the PX-8 as a terminal.

FlUNK

is

used

to

transfer files between the PX-8 and other computers.

These programs are discussed in detail in the following pages.

Other programs are often provided with

CP

1M. These are discussed in section

3.10. Please consult your dealer for further information.

3-32

3.8.2 Application programs

You

will

also use programs such as Portable WordStar™ and Portable Calc™.

They will have instruction manuals which will give you details

of

how

to

use them. Whatever media they are provided on, ROM, Microcassette tape or floppy disk, they will have a file in the directory which

is

a .COM file

to

run them. They are executed in the same manner as the utility programs. They are transient commands

of

a different kind.

3-33

3.8.3

PIP

The

PIP

program

is

used to copy files between peripherals, e.g. from disk to

disk, disk to Microcassette tape, from a disk

to

a printer etc. The name comes

from the initial letters

of

the words Peripheral Interchange Program.

PIP

can be used with wildcards (see section 3.2.1)

to

transfer all types

of

files.

It

can also be used to perform other valuable functions such as:

• Remove

part

of

a file either from the beginning, end or the middle.

• Convert all characters into upper case or lower case

• Join a number

of

files together

• Make a backup

of

a file under a different name

• Add sequential numbers to each logical line

of

text

• Reform the page length

of

a text file

There are two ways

PIP

can be used.

1)

When only a single operation

is

required,

PIP

can be used by following

the command

'PIP'

with the command string

of

the operation you wish

to carry out.

On

completion

of

the operation the

CP

1M

prompt will be

returned or the MENU displayed

if

it

is

switched on. When using

PIP from the MENU the command string can be typed on the MENU command line, when

PIP

has been selected.

2)

When a number

of

operations are to be performed, the

PIP

program

can be loaded into memory. The

CP

1M

prompt

(A>,

B>

etc)

will be

replaced by a

PIP

prompt indicated by

an

asterisk. The use

of

PIP

in

this manner

is

essentially the same as when only one operation

is

re-

quired.

When

PIP

is

chosen from the MENU, unless

an

additional command

string

is

given, the

PIP

screen will clear and the

PIP

asterisk prompt

will appear.

Pressing the

I

RETURN

I key, the I

STOP

I key or I

CTRL

I -

(g

will return

to

the

MENU screen

or

the

CP

1M

system prompt whichever

is

set.

In

using

PIP

the command

is

written

to

perform the operation

to

a particular

drive or device, from a particular drive

or

device. The location

of

the file being

moved always comes last.

3-34

1. COPYING A

FILE

FROM

DRIVE

TO

DRIVE

Any file with a readlwrite attribute can be copied from one disk to another. For

example,

C>PIP

H:

=A:INFO.DAT

This copies the file DEMO.DAT from drive A :

to

drive H:

th<:n

returns. to

the system prompt. The same filename will appear

on

the new dnve. The fIle-

name can be changed, for example:

C>PIP

H:NEWNAME.DAT=A:INFO.DAT

By using this option to copy the file

to

the same drive, it can be used

to

make

a backup

of

a file under a different name.

Various options can be added

to

the end

of

the

PIP

command string. These

are listed starting from item 5. For example specifying the

[V]

option causes

the file to be verified as it

is

copied:

C>PIP

H:=A:INFO.DAT[V]

2. COPYING A

FILE

FROM

DISK

TO

PRINTER

This has almost the same effect as pressing I

CTRL

I -

~

then asking the com-

puter

to

TYPE a file:

C >

PIP

LST: = A:LETTER. TXT

The file will be printed character by character, and words which come at the end

of

a line are likely

to

be split in the middle

of

the word.

This command can also be used

to

list a BASIC file

to

a printer

if

you are

not

in BASIC and do

not

have the BASIC ROM installed.

C >

PIP

LST: = A:DEMO.BAS

The BASIC program

is

sent

to

the printer as

if

you had LLISTed it while in

BASIC. You MUST have saved the BASIC program as

an

ASCII file using

the"

,A"

option in BASIC.,

A refinement

of

this command

is

to

add the option [Pn] where the printer will

3-35

execute a form feed every n lines. This can be used to prevent lines being printed

on

the perforations. For example:

C>PIP

LST: =A:INFO.DAT[P60]

will force a form feed every 60 lines giving the same effect as a one-inch skip-

over

on

paper which takes 60 lines.

Another addition could be

to

echo the file to the screen

at

the same time

as

it

is

printed. This

is

achieved using the

[E)

option:

C>PIP

LST: =A:INFO.DAT[E]

If

both option are required, the command would be:

C>PIP

LST: =A:INFO.DAT[P60E]

3. C.oPYING A

FILE

FR.oM DISK T.o SCREEN

The use

of

this command

will

have the same effect

as

the

[E)

option when copy-

ing from and to any other device.

It

is also the same as using TYPE command.

The format is:

C>PIP

CON:

=A:MEMO.DOC

One

of

the options

that

can be specified here to good effect

is

[N]

or [N2]. This

causes line number

to

be added

at

the beginning

of

each line in the form

01

if

[N]

is

specified .and

ooooel

if

[N2]

is

specified:

C>PIP

CON:=A:MEMO.DOC[N2]

In

addition, all lower case characters can be converted to upper case, and vice

versa, using the

[U]

and

[L]

options:

A>

PIP

CON: = A:MEMO.DOC[N2U]

will give

C)PIP

CON:=A:MEMO.DOCCN2Ul

000001

THIS

IS

A LINE

OF

TEXT

000002

HAVE

A NICE

DAY

C)

3-36

and

A>

PIP

CON: = A:MEMO.DOC[NL]

will give

C)PIP

CON:zA:MEMO.DOCCNLl

C)

1:

this

1s A line

of

text

2:

hAve A nice

day

4. C.oPYING A

FILE

T.o AN EXTERNAL DEVICE

Files can be copied

to

external devices such as printers, disk drives and other

computers by specifying the relevant output port

as

the destination. For instance:

A>PIP

TTY:=A:DEMO.BAS

will copy the file

to

a printer

or

any other device connected

to

the high-speed

serial output port.

5 • .oPTIONAL PARAMETERS AVAILABLE

WITH

PIP

There are nineteen options which can be used with the

PIP

command, includ-

ing those which have been mentioned already:

1. Block mode transfer

'i.IIIM'

[B]

This option causes the data

to

be copied across in blocks, that is,

256

b~es

at

a time. When the buffer has received a block

it

sends the data to the destma-

tion device before allowing the source device

to

send it the next block. The ac-

tual character it recognises as an end-of-block marker

is

ASCII code

19,

that

is,

I

CTRL

I -

[ID

or

X-OFF.

A>

PIP

TEST .FIL = CRT:[B]

2. Echo to screen

'1.1;;;'"

[E]

Giving this option will cause the screen to display all the data being transferred so that you can

see

what

is

being copied across during the process.

'4MlllhB

A>

PIP

LST: = TEST .FIL[E]

3-37

It

is

advisable to user the

[V]

entry, i.e.

to

verify the file when using the

[E]

option in copying files.

3. Form feed insertion

1i.I'@1I

[Pn]

This makes it possible to force a form feed every n lines.

It

is

particularly useful when sending files to the printer, allowing it to skip the perforations in continuous stationery

to

improve legibility.

If n is

omitted or given as 1

PIP

assumes

a form feed

is

required every 60 lines (that is, the default setting).

If

your paper

requires

66

lines per page use the parameter as in the following example:

A>

PIP

LST: = REPORT. TXT[P66]

If

used with the next parameter, [F], the

[F]

should come first:

A>

PIP

LST: = REPORT. TXT[FP66]

4. Form feed suppression

1i.I'@"

[F]

This

is

most useful when using

PIP

with a printer.

It

suppresses the form feed

character (ASCII code

12

or

hex

OC)

which would otherwise cause the printer

to

feed a sheet through when it encounters the code.

It

is

as well to remember

that

this code

is

also the 'clear screen' code, so it

is

advisable

to

take care when

using this option.

14Mintm

A>

PIP

TTY: = TEXT .DOC[F]

In conjunction with [Pn] it can be used

to

reform page lengths, by copying a file, removing previously added form feeds (e.g. ones inserted by PORTABLE WORDST AR) and adding them

at

a different place.

5. Hex format

Ii.II@1I

[H]

When this option

is

specified the

data

is

checked

to

ensure it

is

in Intel

HEX

format.

If

there

is

a discrepancy it terminates the transfer.

A>

PIP

DEM02.HEX = DEMOl.HEX[H]

3-38

6. Ignore NULL records

...1111611

[I]

This can be used as an alternative

to

[H]

- it causes

PIP

to ignore NULL records

(hex 00) and ensures the

data

is in Intel

HEX

format.

It

is

therefore an exten-

sion

of

the

[H]

option.

14Mllllm

A>

PIP

DEM02.HEX = DEMOl.HEX[I]

7. Lower case conversion

".!I@II

[L]

Using this option will convert all upper case characters into lower case as they are transferred.

14$1"'m

A>

PIP

LST: = C:LITTLE.DOC[L]

8. Numbering lines

".!I@II

[N]

[N2]

When sending programs to another device it may be useful to have the lines numbered.

PIP

regards a line as a series

of

characters terminated by a carriage

return (ASCII code

13

or ODH). Specifying

[N]

will begin the file at column

9, with a colon(:)

at

column 7 followed by a space. The number

of

the line will

be placed before the colon, as the following example shows:

If

the file TEST .DOC contains the following information:

This

is

line one

This is line two

*

This

is

line ten

*

This

is

line one hundred

where the text would also correspond

to

the numbers

of

the lines as seen by

PIP,

and the asterisks refer

to

further lines

of

text.

If

the file

is

transfered to

from drive D:

to

drive A: using the

[N]

option, using:

C>

PIP

A: =

D:

TEST .DOC[N]

3-39

The file

on

drive A: will have the lines numbered

as

follows:

1:

This

is

line one

2:

This

is

line two

*

'-~

10:

This

is

line ten

*

100:

This

is

line one hundred

Similarly specifying

[N2J

fills in all leading spaces with a zero and replaces the

colon with a space. For example

if

the following command

is

given:

C>

PIP

A: = D: TEST .DOC[N2J

the file on drive A: will have the lines numbered

as

follows:

000001

This

is

line one

000002 This

is

line two

*

000010 This

is

line ten

*

000100 This

is

line one hundred

If

you wish

to

display the file with numbered lines

on

the screen, use:

C>PIP

CON:=D:

TEST.DOC[N] or C>

PIP

CON: = D: TEST .DOC[N2]

9. Object file transfer

""'IIG"

[0]

Normally

PIP

can only copy standard ASCII

or

HEX

files, but using this op-

tion allows it to transfer other types

of

files. Its effect

is

to

ignore the physical

end-of-file code a CTRL-Z (ASCII

26

or 1A hex) wherever it occurs in the ob-

ject file, because in this context it will not be signalling the end

of

the file.

14l1li6

A>PIP

B:=OBJECT.FIL[O]

3-40

~~

r:

:"

~

---

r-;

"",'I

r~

'If"!

~-'

~

...,,;

1tJJJ!

~

.~

'f1/f!

~

.'"

~

,...'"

;"

--

liB"

~

---

t!"'"

~

-.,p

~

It

is

not necessary to use this optional parameter with a COM file, because

PIP will automatically add it. However, when using it with other machine code or object

files

which do not have the file extension COM, the

[OJ

parameter MUST

be used.

10. Read system files

".Ii

IlL"

[R]

This option makes it possible to read and copy system files, that is, files which do not appear in the directory and those with a filetype

of

SYS.

It

automatical-

ly sets the

[WJ

option.

14$l1li6

A>

PIP

B: = A: OSTAB.SYS[R]

11. Stop copying

at

specified string

'i"'IIL"

[QstringI\Z]

(I\Z

means type a I

CTRL

I -

00

by holding the I

CTRL

I key down while press-

ing the Z key.)

If

you only want

to

transfer part

of

a file, giving this option will cause

PIP

to

copy the file until it finds the specified string. Only text before the string

will be copied.

'4l1li6

A>

PIP

LST: = B:REPORT .DOC[QTHE ENDI\Z]

If

you want

to

search for a string containing lower case characters this can only

be used from the

PIP

* prompt. This

is

because

CP

1M

converts everything

typed

on

the command line into upper case including the string you have given

and

PIP

will not be able

to

find it, because it

is

searching for the upper case

equivalent

of

your string.

14l1li6

* LST: = B:REPORT .DOC[QTbe Endl\Z]

It

can be used with the next option

to

copy a section from the middle

of

a file.

12. Start copying

at

a specified string

...i'IIL"

[SstringI\Z]

This behaves in much the same way

as

the [Qstringl\ZJ option, except that it

starts copying from the end

of

the specified string. The same conditions apply

3-41

if

you want to detect lower case characters.

';¥IUiS

~

PIP

TRODUCflONI\Z]

CHAPTER1.DOC = CHAPTER1.DOC[SIN-

The two options can be used together

if

you want to copy a piece

of

data

from

the middle

of

a file.

IAiiiim

* CHAPlER1.DOC= CHAPfER2.DOC[SIntroduction I\ZQlast.I\Z]

13. Tab settings

",!h.'"

[Tn]

The tab settings

on

the copied file can be changed from those

of

the original using this option. The number given by n puts tabs at columns n, 2n, 3n etc. For

instance,

[T9]

will give tabs

at

columns 9, 19, 29,

39

and so on. These set-

tings will be used wherever

PIP

comes across a TAB character in the file it

is

copying. The TAB character

is

I

CTRL

I -

rn

(ASCII code 9).

If

the word processor ,

or

whatever created the text file, inserts spaces instead

of

using the TAB character, this option will have no effect.

';¥IUiS

A>

PIP

CON: = B:PROGRAM.ASM[T10]

14. Transfer between user areas

h.!l@"

[Gn]

Normally it

is

not possible to use files from another user area. However, specify-

ing this option will allow transfer

of

files from user area n to the current area.

';'!IiIS

C >

PIP

A:TEST.DOC = A:DEMO.DOC[G3]

15. Truncate lines

of

data

",!h""

[Dn]

This option allows truncation

of

lines past column n,

that

is,

PIP

will delete

all characters between column n and the next carriage return.

';$!IiIS

A>

PIP

LST: = PROGRAM.BAS[D80]

3-42

16. Upper case conversion

h.nllM.

[U]

This works in the opposite sense to the

[L]

option in

that

it converts all lower

case characters to upper case.

'4$illiS

A>

PIP

TTY: = BIGTYPE. TXT[U]

17. Verify the copy

h,I"""

[V]

Verifying a file as it

is

copied acts as a double check

on

its integrity. When given

this option

PIP

compares the copy it has made with the original as it goes along,

ensuring a faithful reproduction containing only those errors

that

were in the

original.

l4$illiS

A>PIP

B:=PERFECT.COM[V]

18. Write to a read/only file

h.n@"

[W]

If

you have files which have been set

to

read-only using STAT, you can copy

over them

if

you give this option without the computer asking you

if

you want

the existing file erased and overwritten. As it

is

not possible to reverse the process

if

you make a mistake, use with care!

';$hIIS

A>

PIP

A: = B:SECURE.COM[W]

19. Zero parity setting

h.ll@"

[Z]

The leftmost bit

of

a byte

is

usually the parity bit,

and

this option sets all these

high-order bits to zero.

It

results in converting 8-bit ASCII bytes to 7-bit AS-

CII

bytes.

It

is

as well to ensure none

of

the characters you are sending use

this bit because otherwise you could get some unexplained results.

For

example graphics characters would be changed, and some console ESC codes would be changed.

A>

PIP

C: = B:ORDINARY .FIL[Z]

3-43

USINGjTHE

PIP * PROMPT

If

you want

to

transfer a large number

of

files

or

transfer files between two

data disks, it may be more convenient to give the

PIP

command

on

its own,

producing the

* prompt:

The command string as described above can then be typed for each operation. For example to copy all the COM files to drive A: from drive C:, the display would show:

C)PIP *E:aC:*.COM

COPYING

-

PIP.

COM

STAT.

COM

SUBMIT

.COM XSUB.COM FILINK.COM TERM.

COM

CONFIG.COM

*

Or

to output a file

to

the screen:

C>PIP

* CON:

=MEMO.DOC

At

the * prompt you can type in any

PIP

commands you like without having

to

load

PIP

on

every operation. This can save a great deal

of

time

if

there are

a number

of

operations

to

be carried out.

One you have finished, pressing the

I

RETURN

I key, the I

STOP

I key

or

I

CTRL

I -

[g

will return you

to

the system prompt

on

the drive form which

you entered

PIP

(the default drive),

or

to the MENU

if

it

is

switched on.

3-44

The STAT program

is

used

to

find

out

the STATistics

or

STATus

of

the vari-

ous disk drives. This makes it the most frequently used

of

the utility programs.

Many

CP

1M

users do not use the full facilities provided by STAT. The follow-

ing information

is

therefore provided

as

a list

of

operations, with a summary

at

the end. STAT and the Microcassette Drive

Because the Microcassette drive

is

not a standard

CP

1M

disk device, but

is

a

sequential tape device, the STAT program cannot determine the correct data

for space on the Microcassette Drive. Also

file

name lengths may not be accurate.

3-45

USE OF

THE

STAT PROGRAM

1.

CHANGE

DEVICE ASSIGNMENTS

'i.!lIl6"

STAT logical: = physical:

The device assignments can be altered with this command. However, it

is

more likely that the CONFIG program would be used instead since the devices are named in real terms rather than as codes.

For those familiar with

CP/M

who are used

to

using the STAT command, the following table shows the correspondence between the physical devices and those implemented:

Logical

Physical device

device

LST:

TTY:

CRT:

LPT:

ULl

Serial (printer) LCD display RS-232C not implemented

PUN: TTY:

PTP:

UPI:

UP2:

not implemented LCD display RS-232C not implemented

RDR: TTY:

PTR:

URI:

UR2:

Keyboard not implemented

RS-232C not implemented

CON: TTY:

CRT: BAT: UCI:

Output RS-232C

LCD RS-232C RS-232C

Input Keyboard

Keyboard RS-232C RS-232C

For instance, to tell the computer that the printer

is

now attached to the serial

port instead

of

the RS232-C port, the command

C>STAT

LST : =

TTY:

is

given, after which all output destined for the printer

is

sent to the serial port

instead

of

the RS-232C port. Then,

if

the STAT DEV: command

is

given, the

result will be:

3-46

C)STAT

DEV:

CON:

1s

CRT:

RDR:

1s

URi:

PUN:

1s

UPi:

LST:

1s

TTY:

C)

Further details

of

the physical devices assigned to the logical devices are given

in section 3.6.

2. DISK CHARACTERISTICS

'i.!lIl6"

STAT DSK:

The complete status

of

a disk

is

displayed using this command.

It

shows the

status

of

both the current disk and

that

of

any others

that

have been accessed

during the same session:

This command displays the characteristics

of

the disks accessed, such as its ca-

pacity for example:

A>C:STAT

DSK:

A: Drive characteristics

72: 128 Byte Record Capacity

9: Kilobyte Drive Capacity

16: 32 Byte Directory Entries

8:

Checked Directory Entries

128: Records/Extent

8: Records/Block

64: Sectors/Track

8: Reserved Tracks

3.

HELP

...

11116"

STAT VAL:

(drive name) (no.of

128 byte records allowed)

(formatted capacity

of

drive)

(no.and size

of

directory entries)

(no.of

checked directory entries)

(no.of

records per extent)

(no.of

records

per

block)

(no.of

sectors

per

track)

(no.of

tracks reserved for

CP/M)

This acts as a sort

of

HELP

command.

It

shows the formats

of

the various

STAT commands which can be given to obtain information or alter device at-

tributes and assignments:

3-47

C>STAT

VAL:

"--

Temp

R/O

Disk: d: =

R/O

Set Indicator: d:filename.typ

$R/O

$R/W

$SYS $DIR Disk Status: DSK: d:DSK: User Status: USR: I/O

byte Assign:

CON: = TTY: CRT: BAT:

UCI:

RDR:=

TTY:

PTR:

URI:

UR2:

PUN: = TTY:

PTP:

UPI:

UP2:

LST:=

TTY: CRT: LPT:

ULI:

4. DISPLAY DEVICE ASSIGNMENTS

".imSIl

STAT DEV:

This gives the details showing which logical devices have which physical devices assigned to them.

To

check the devices by name, use the CONFIG program.

C>STAT

DEV:

CON.

is

CRT:

RDR:

is

UR1:

PUN:

is

UP1:

LST:

is

LPT:

C>

5.

READ/ONLY -PROTECT

ALL

THE

FILES ON A DISK

".ime"

STAT drivename: =

R/O

An

entire disk can be set to read/only with this command.

It

remains effective

until either a warm or a cold start

is

made:

C>STAT

A:=R/O

The Read/Only command protects the files on a disk so

that

they cannot be

erased

or

written to.

If

you try to write

or

erase a file with a

R/O

attribute

set the error message:

A>

ERA LETTER.DOC

BDOS

ERROR

ON

A:R/O

will be displayed. Pressing either the

I RETURN 1 key or thel STOP

Ikey

or I CTRL

1-

(g

will return

3-48

you to the prompt.

It

is

also possible

to

protect single files and unprotect them using STAT.

6.

READ/ONLY -PROTECT

A SPECIFIED

FILE

".I;;;SII

STAT drivename:filename.filetype

$R/O

Any file can be set to read/only using this format. This will prevent any altera-

tion

of

the file until it

is

reset to read/write:

C>STAT

A:DOCUMENT.TXT

$R/O

DOCUMENT.TXT set to

R/O

7.

READ/WRITE

- REMOVING PROTECTION

".1111ij1l

STAT drivename:filename.filetype

$R/W

This resets a file to allow it to be written to as well as read from.

C>STAT

A:DOCUMENT.TXT

$R/W

DOCUMENT.

TXT

set to

R/W

If.

a file

is

protected,

and

subsequently the whole disk

is

protected, the file will

stIll be protected when a warm

or

cold boot

is

made

to

remove the protection

from the disk.

8.

HIDE

FROM DIRECTORY - SPECIFIED

FILE

....

;;;"'-

STAT drivename:filename.filetype

$SYS

It

is

possible to give a file SYStem status using this command. This effectively

removes its name from the directory so it cannot be used by anyone who does not

know it exists:

C>STAT

A:DOCUMENT.TXT $SYS

DOCUMENT.

TXT

set to

SYS

If

a STATus

is

carried out on the file when it

is

set

to a SYS

file

it

shows with

the filename in brackets

3-49

C>STAT

A:DOCUMENT.TXT

Recs Bytes Ext Acc

41

6k 1

RIO

A:(STAT.COM)

Bytes Remaining

On

A: 3k

9.

REPLACE

IN DIRECTORY -

SPECIFIED

FILE

Ii,li@"

STAT drivename:filename.filetype $DIR

This countermands the previous format, resetting the file so

that

it shows

on

the directory:

C>STAT

A:DOCUMENT.TXT $DIR

DOCUMENT.TXT set to

DIR

10. SIZE AND ATTRIBUTES -

SPECIFIED

FILE

Ii,Ji@"

STAT drivename:filename.filetype

The size

and

attributes

of

the specified file are displayed using this command.

It

gives specific information about the number

of

records (Recs), number

of

bytes (Bytes), number

of

extents (Ext) and read/write status (Acc)

of

each file

on

the disk, then the total number

of

unused bytes remaining. A complete file

name can be given,

or

wildcards can be used to specify a number

of

files:

a) Information

on

a particular file

C>STAT

A:TESTING.COM

Recs Bytes Ext Acc

16 4k 2

RIO

A:TESTING.COM

Bytes Remaining On A: 4k

b) Information

on

all files

C>STAT

C:*.*

Recs

Bytes

Ext

Acc

64

8k

1

R/W

C:CONFIG.COM

22

3k

1

R/W

C:FILlNK.COM

58

8k

1

R/W

C:PIP.COM

41

6k

1

R/W

C:STAT.COM

3-50

10

24

6

2k 3k 1k

1

R/W

1

R/W

1

R/W

Bytes remaining

on

C:

C:SUBMIT

.COM C:TERM.COM C:XSUB.COM 33k

c)

All files with a particular extension

C>STAT

A:*.COM

Recs Bytes Ext Acc

58

8k 1

R/W

A:

PIP

.COM

Bytes remaining

on

A: 0k

d) Files containing particular characters

A>STAT

D:DEMO??BAS

Recs

Bytes Ext Acc

20

3k

1

R/W

D:DEM01.BAS

16 2k

1

RIO

D:DEM013.BAS

14 2k

1

R/W

D:DEM01A.BAS

Bytes remaining

on

D:

258k

11. SIZE AND ATTRIBUTES - SPECIFIED

FILE

1I0II@"

STAT drivename:filename.filetype

$S

Using this form

of

the command will give the same information as without the

$S

option, with the addition

of

the size

of

the file. This value

is

the same as

the number

of

records for sequential access files, and is generally used to show

the amount

of

space

that

has been reserved for a

random

access file. This

is

because a sequential file simply takes up space as it

is

added to, and a random

access file has

an

amount

of

space allocated to it when it

is

created:

C)STAT A:

DOCUMENT. * $S

Size

Recs

Bytes

Ext

Ace

1 1

lk 1 R/W A:

DOCUMENT.

BAS

1

11k

1

R/W A:

DOCUMENT.

TXT

Bytes

Remaining

On

A:

6k

C>

3-51

12.

SPACE

REMAINING

ON

DISK

h.!lM"

STAT

Giving this command

at

the

prompt

will result in a display

of

the

amount

of

space available

on

the current drive and

on

any other drives which have been

accessed during the current session.

It

also shows the read/write attribute:

a)

C>STAT

C:

RIO,

Space: 33k

b)

C>STAT

A:R/W,

Space:

ill<

C:R/O,

Space: 33k

H:R/W,

Space: 24k

13.

SPACE

REMAINING

ON

SPECIFIED

DISK

h.lm611

STAT drivename:

This form

of

the command gives the

amount

of

space remaining

on

specified

drive:

C>STAT

A:

Bytes Remaining

On

A:

ill<

14.

USER

STATUS

h.liieFll

STAT USR:

This format is used

to

display the number

of

the current user

and

the numbers

of

the users who have active files

on

the disk:

A>

STAT USR:

Active

User:

0

Active Files : 0 1

This gives the information

that

the current user

is

number 0 and

that

users 0

and 1 both

have active files

on

the disk.

3-52

SUMMARY

OF

STAT COMMANDS

STAT SPACE REMAINING

ON

DISK

STAT DEV: LOGICAL

TO

PHYSICAL ASSIGNMENTS STAT drivename: SPACE REMAINING ON SPECIFIED DISK STAT

drivename:=R/O

READ/ONLY

- SET SPECIFIED DISK STAT drivename:filename.filetype SIZE AND ATTRIBUTES - SPECIFIED FILE STAT drivename:filename.filetype $DIR REPLACE

IN

DIRECTORY - SPECIFIED

FILE

STAT drivename:filename.filetype

$R/O

READ-ONLY - SET SPECIFIED FILE

STAT drivename:filename.filetype

$R/W

READ/WRITE

- SET SPECIFIED FILE

STAT drivename:filename.filetype

$S

SIZE AND ATTRIBUTES - SPECIFIED FILE

STAT drivename:filename.fi1etype $SYS REMOVE FROM

DIRECTORY-

SPECIFIED

FILE STAT DSK: DISK STATUS STAT logical: = physical: CHANGE DEVICE ASSIGNMENTS STAT USR: USER STATUS STAT VAL:

HELP

3-53

3.8.5

SUBMIT/XSUB

Two very useful commands available in

CP

1M

are SUBMIT and XSUB. Sup-

pose you wish to execute the same commands in a certain sequence

at

various

times. Instead

of

having to type in the commands one by one you can put them

all into a special file with the extension .SUB. Then when you want

that

series

of

commands executed you can simply type

C>

SUBMIT filename

and they will all be executed one by one. You can use the XSUB command to allow for input from the keyboard when running programs listed in the SUBMIT file by inserting it

at

the beginning

of

the file.

The most useful aspect

of

having a SUBMIT file facility in

CP

1M

on

the PX-8

is

to enable a whole sequence

of

files to be run from

an

AUTOST ART

or

WAKE

string. Section 2.2.3 shows how to set

up

these strings.

1. SUBMIT

First

of

all you need to make a list

of

the programs you want to run. These

must all be programs which will return to the

CP

1M

system

prompt

when they

end because otherwise the next command in the sequence cannot be executed.

It

is

possible

to

run

other types

of

programs,

or

ones which require input from

the keyboard, providing you are present

to

type in

at

the keyboard when

necessary.

The files containing the commands can be created in a variety

of

ways - any

word processing program such as Portable WordStar™, a BASIC program

or

using the

CP

1M

ED

program

if

you have it.

Here

is

an

example

of

a simple batch

of

jobs

to

be carried out:

1.

Display a directory

of

the disk

on

the D: drive;

2. Show the sizes

of

the files;

3. Erase all those with the extension .BAK (that is, back-up files);

4. Move all BASIC files to the disk in the E: drive.

The sequence

of

commands to do this would be:

DIRD: STAT

D:*.*

3-54

ERA

D:*.BAK

PIP

E: =

D:

* .BAS

If

this series

of

commands were held in a file called START .SUB the command

to execute them will be:

A>

SUBMIT START

The commands will be executed one by one, and each one will be shown

on

the screen before it

is

run, just as

if

you had typed it in from the keyboard.

If

you want

to

run

a BASIC program from SUBMIT, remember that when such

a program ends

it

returns to the BASIC

'Ok'

prompt

instead

of

to

CP/M,

so the next command in the SUBMIT file will not be executed. One way round this

is

to

insert a line in the program:

65989 SYSTEM

This will ensure a return

to

CP

1M

at the end

of

the program.

If

one

or

more

of

the progams you want to be executed may vary, it

is

possible to insert variables into the SUBMIT file which can be substituted when the submit program

is

run. The variables symbols are inserted in the form

"$1",

"$2",

"$3"

etc, where

"$1"

is

the variable symbol used for the first substitution,

"$2"

for the second and so on. The values

of

the variables are substituted ac-

cording

to

the following syntax:

C>

SUBMIT filename

Xl

X2 X3 ..•..

where

Xl

will substitute all values

of

"$1",

X2 all values

of

"$2"

and so on.

For

instance

if

the SUBMIT file BEGIN .SUB contained

DIR

D:*.BAS

B:BASIC

$1

STAT D: * .BAS

the command given could be

C>SUBMIT

BEGIN

D:PROGI

3-55

This has the effect

of

inserting the filename you have given (D:PROG1) into

the variable

"$1"

in the SUBMIT file. The result would be to display a direc-

tory

of

the disk in drive B: and then load BASIC from drive

B:

before running

the BASIC program

PROG 1 on

the disk in drive D: and then showing the BASIC

files

on

drive D:.

There can be any number

of

variables in the SUBMIT file, and you must en-

sure

that

the filenames you give are in the correct order to be substituted

at

the appropriate time.

For

instance,

if

you have a SUBMIT file TESTING .SUB

containing the following commands:

DIR

$1

DIR

$2 STAT $3

DIR

the command you give

to

execute it with the .COM files TESTA, TESTB and

TESTC in

that

order should be:

C>SUBMIT

TESTING TESTA TESTB TESTC

so

that

they are substituted in the correct order.

Some

CP/M

programs

(PIP

for example) use the

"$"

character in their sub-

commands, and

if

this will mean they will be interpreted as variables. Conse-

quently care must

be

taken as follows to overcome this by adding

an

extra

"$"

whenever the subcommand uses a

"$".

SUBMIT will then ignore the first one

and then treat the second one as normal.

For

example to insert the command

to

cause STAT to set all files

on

disk A: as Read/Only use:

STAT

A:*.*

$$R/O

WARNING: The

SUBMIT

program writes a temporary file when it runs. This file will

be written to drive

A:

and

if

the disk is write protected,

an

error will be

generated and

you

will

not

be able to proceed further. Similarly

if

the

RAM

disk

A:

is set to zero bytes a

"DIRECTORY

FULL"

error will be

generated.

3-56

~

-'~

:~

1.-. 1.1. Creating a SUBMIT file in BASIC

-,

--

~

Since the PX-S

is

not supplied with the

CP/M

program ED, and you may not

W"J

r have a wordprocessor program, BASIC may be the only means

of

creating a

.,

r

'~..

SUBMIT file. This can be done very simply by creating a sequential text file and writing the commands to it as data. Chapter 5

of

the BASIC Reference

;,

I

~

Manual gives details

of

creating text files.

For

instance, the series

of

commands

~

1 given above could be put into the file called START.SUB with the following

'VJ

("

"Ill'

I

.~

e~ I /~

,.\

.~

,.,.

I

~

'-'/

I

~

.~

- I

/''"\

C

Y'

I "

~

I Y

~

J

~l~

~L

j

~

--:j

eL~

~

t,",

;L~

~l~

;

L,?

;L~

;:

L'"'"\

~~

~.".~

:~

program:

10

OPEN

"0",

#

1,

"D:START.SUB"

20

PRINT # 1,

"DIR

D:"

30

PRINT # 1,

"STAT

D:

*.

* "

40

PRINT # 1,

"ERA

D: * .BAK"

50

PRINT # 1,

"PIP

E: = D: *

.BAS" 60 CLOSE 70

END

Or, put another way:

10

OPEN

"0",

#

1,

"D:START.SUB" 20 READ A$ 30 IF A$

=

"END"

THEN

60

40

PRINT # 1,

A$ 50 GOTO 20 60 CLOSE 70

END

S0

DATA

"DIR

D:",

"STAT

D:

*.

*

'~'ERA

D:

*

.BAK'~'PIP

E: =

D:

*.B

AS'~'END"

Either

of

these programs will create a file called START.SUB containing the

commands you want which can then be executed from the

CP/M

prompt by

typing:

C>SUBMIT

d:START

You could even write a utility program in BASIC

to

allow you to create a SUB-

MIT

file at any time by putting in the commands as you go and then storing

them in a .SUB file

of

your choice:

10

INPUT

"Type

in drivename and filename

";F$

20

OPEN

"0",

#

1,

F$ +

".SUB"

30

INPUT

"Enter

command

or

END

";A$

3-57

40 IF A$ =

"END"

THEN

70

50

PRINT # 1,

A$ 60 GOTO 30 70 CLOSE 80

END

1.2 Creating a SUBMIT file with Portable

WordStar™

You can create a SUBMIT file with any word processing program,

but

the ex-

ample given here deals specifically with Portable WordStar™.

In

fact the proce-

dure will be almost identical regardless

of

which word processor you use.

First

of

all you must create a new document, giving it the name.

Filename. SUB

If

you do

not

give the extension .SUB the program will not allocate the exten-

sion .SUB and the file you have created will

not

work with SUBMIT.

Now all you have

to

do

is

type in the commands you want, one

on

each line

and each followed by a carriage return:

A:FILENAME.SUB

PAGE 1 LINE

5 COL

91

L----!

----! ----! ----! ----! ----! ----! ----! ----! ----! ----! ---------R

DIR D : I

RETURN

I

STAT

D:

*.

* I

RETURN

I

ERA

D: * .BAK I

RETURN

I

PIP E: = D: * .BAS I

RETURN

I

< <

<

Once you have saved this back

to

disk you will be able to execute

it

in the nor-

mal way using the SUBMIT command.

1.3 Adding Comments to SUBMIT Files In

many cases SUBMIT files will be short and easily understood. As you use

SUBMIT more, you

will

realise how powerful a program it

is

and build up more

complex files.

It

is

often difficult to understand why they were created in a specif-

ic fashion, and also

if

someone else wishes

to

understand what you have done, they may not be able to follow your file. This may be overcome by adding comments to the SUBMIT file which are not executed, but can be found by loading the SUBMIT file into Portable WordStar™

or

another word processor,

or

us-

ing the

TYPE

command

of

CP

1M

to

read the file. Comments can be added

3-58

by preceding the comment by a semicolon.

For

example:

DIR

D: ;first show a directory

of

disk in drive d:

STAT D: * . * ;then show the statistics

of

the files

on

the disk

ERA

D: * .BAK ;and erase all backup files

on

drive d:

3-59

2. XSUB

Some

CP/M

programs expect information

to

be typed in

at

the keyboard when

the program has been loaded. The

CP/M

utilities

DDT

and

ED

are two such programs. They can only be used in this way. In order to use them with SUBMIT it is necessary to use the XSUB program with SUBMIT.

If

the

PIP

program

is

to be used

to

carry

out

a number

of

operations, it is normally loaded first and then the individual operations typed from the keyboard after the

PIP

asterisk

prompt

(*).

These subcommands can be included in a

SUBMIT

if

the XSUB program

is

included also.

To

use XSUB

it

is typed into

the SUBMIT file as the first command.

For

example, the operations

1.

Move the files to be updated from the D: drive

to

the E: drive;

2. Execute the program

A:UPDATE.COM;

3. Move the updated files to the

H:

drive;

4. Move the original files

to

the E: drive as back-up files;

5. Erase the original files from the D: drive.

would be executed by a SUBMIT file containing the following commands:

XSUB PIP E: =

D:RECORDS.DAT

"C

A:UPDATE PIP

H: = E:RECORDS.DAT E:RECORDS.BAK =

D:RECORDS.DAT

"C

ERA

D·:RECORDS.DAT

While this file

is

executing you would see the

PIP * prompt

appear when

PIP

was being executed,

and

the names

of

the files being moved exactly as you en-

tered them in the SUBMIT file, as would be the case

if

you typed them from

the keyboard. The fourth and ninth commands are

'C'

which means

"CTRL-

C"

- this is the command given

to

exit from

PIP,

and has

to

be given in the

SUBMIT

file

to allow return to the

CP/M

prompt.

An

alternative

is

'M'

(CTRL-

M) which

is

a carriage return

and

has the same effect

of

leaving

PIP

and

going

back

to

CP/M.

When

PIP

has exited

to

the

CP/M

command line, the program

UPDATE

will be executed. Such a program MUST exit normally

to

the

CP/M command line when being used in a SUBMIT file. When the program UPDATE has finished,

PIP

can carry out a further transfer

of

records.

3-60

~~

:~

:r:

~3.8~.6_C_O

__

N_F

__

IG

________________

__

...

1-' The

CONFIG

program is used

to

set those system parameters which are

not

;;.

~

changed very often.

It

is complementary

to

the System Display, and the cur-

-

~

"'Hf

~

'f1K!

'fl'

~

.".,

-?

~

:-'

\-

~

..

')

-

C

"

~

--

-

~

••

~

."

rent values

of

some

of

the parameters changed

by

the

CONFIG

program are

shown

on

the System Display. The CONFIG program can also be used

to

check

the settings

of

parameters

not

shown

on

the System Display.

WARNING:

Do not switch

off

the PX-8 (either manually or by allowing the auto power

off

to be activated) after changing the

RAM

disk or USER BIOS size without exiting from the CONFIG program. The full configuration can only be carried out by

CP/M.

If

the PX-8

is

switched off, the

RAM

disk could be destroyed and it may also be necessary to re-initialise the system. You will see repeated message

of

"RAM

disk format

(Y/N)"

until

you

press Y(es) key.

When you have entered

CONFIG,

either from the

MENU

or

CP/M

command

line, the screen will show the following:

***

MAIN

MENU

***

Select

alphanumeric

or

ESC

to

exit.

l=auto

power

off

2=CP/M

function

key

3=cursor & function

key

display

4=date & time

5=disk

drives

6=printer

CONFIG

V1.0

7=RAM

disk

8=RS-232C

9=screen

mode

A=serial B=user

BIOS

C=country

The

CONFIG

program

is

used in a similar way

to

the System Display ,but with

12

options. As with the System Display the ESC key is used

to

move back

to

the main menu

and

to

exit.

1.

AUTO

POWER

OFF

FUNCTION

Press the 1 key from the main CONFIG menu

to

change the auto power

off

time. The screen will clear and change to:

***

AUTO

POWER

OFF

***

Set

time(l

to

255)

in

minutes

or

ESC

to

return

(0

disables

auto

power

of

Auto

power

off

time

?

auto

power

off

:

10

3-61

The value shown against the semi-colon

on

the fifth line

is

the current setting

in minutes for the auto power

off

time. This

is

the time for which the PX-8

will wait before switching itself

off

in continue mode

if

no key

is

pressed.

It

is

advisable to keep the time short, otherwise the battery will

run

down. The

reason for having such a system

is

to conserve the battery.

As can be seen from the display, the time can be set in intervals

of

one minute

(up to

255

minutes)

or

switched

off

altogether using the value

O.

When you have entered the time you require, press RETURN. The chosen time will be displayed

on

the fifth line, and you can use the ESC key to return to the main

CONFIG menu.

2. The

CP

1M

FUNCTION

KEY ASSIGNMENTS

When the 2 key

is

pressed

on

the main CONFIG menu, the display changes to:

***

CP/M FUNCTION

KEY

***

Select

function

key

number

(PF10=0)

or

ESC

to

return.

PFI

dir

PF2

type

PF3

stat

PF4

pip

PF5

conf

i

g·

....

M

PF6

dump

PF7

submit

PFB

ddt

PF9

term··'M

PF10

filin~c"M

These are the strings assigned to the programmable function keys

on

the top

of

the keyboard. A description

of

the use

of

the keys

is

given in Chapter 2 section 2.2.1c. The screen above shows the default setting, i.e. the strings which will be assigned when the system

is

initialized

or

a reset

is

performed.

Note that when shown

on

the eighth line

of

the

CP/M

screen, some

of

the strings

terminate in the

--1

character. In setting them up with the CONFIG program,

this carriage return

is

shown as

"J\M".

These strings have a carriage return

(CTRL-M) added to them because there

is

no possibility

that

any more charac-

ters need to be typed after the string.

For

example the PF5 key can be used

to run the CONFIG program as follows. On the

CP/M

command line type the

drive name where the CONFIG program

is

located (e.g. C:) and then press the

PF5 key. All the letters

of

the word CONFIG

will

appear, and the carriage return

will be 'typed' also.

In a few

seconds the

CONFIG

main menu will appear

on

the screen.

The CTRL-M

is

not

added to all commands since some

of

them might possibly

require extending.

For

example with

DIR

you might want to add the name

of

3-62

a drive other

than

the current one to find

out

the files

on

that

particular drive

instead

of

changing the logged in drive first. When the

~key

is

pressed, the

letters

"DIR"

are printed, and the PX-8 will wait for any further input.

If

you

simply press the

I

RETURN

I key, the directory

of

the current drive will be print-

ed.

If

you press the space bar and then the two keys

"C:"

followed by the

I

RETURN

I key, the directory

of

the C: drive will be printed

on

the screen.

To

change the assigned string, press the number corresponding to the

PF

key

(i.e. 1 for

PFl,

2 for PF2 etc, remembering

that 0 is

used for PFI0). The se-

cond line

of

the screen will display the message:

Terminate function key string with

HELP

and the third line

of

the screen will then display the name

of

the key whose

function

is

to

be changed, with the cursor

to

the right

of

it awaiting input.

Up

to

15

characters can be inserted into each

PF

string.

If

a control key

is

to be

added, e.g. a carriage return (CTRL-M), this MUST be added by pressing the

I CfRL I and the appropriate alphabetic key. However, in the special case

of

the

carriage return simply pressing the

I

RETURN

I key will add the characters

"J\M"

to denote the CTRL-M for the carriage return. This counts as one character of

the string, although it

is

displayed as two (

"J\"

and

"M")

in this section

of

the

CONFIG

program.

If

a control character has been added correctly, the

backspace (

~)

key will remove it as a pair

if

the

[]§J

key

is

pressed once.

When a carriage return

is

inserted correctly it will be seen

on

the function key

display line as a

..-J

character.

If

the characters

"J\M"

appear

on

the function key display line, they are represented as those characters and DO NOT REPRESENT A CARRIAGE RETURN.

For

example

if

the function key dis-

play line shows

"DIRJ\M"

for one

of

the keys when the corresponding key

is

pressed, all five characters will be displayed and the cursor will be placed

at

the right

of

the last one awaiting further input.

Although the string can consist

of

up

to

15

characters,

if

more

than

seven are

assigned

to

the string, only the first seven will be seen

on

the function key dis-

play line. However,

if

the function key

is

pressed the complete number

of

charac-

ters will be printed to the screen.

If

a wrong character

is

input, the backspace key ( ~ ) can be used

to

erase

the previous character. Because the

I

RETURN

I key can be use to enter the carriage return as a

"J\M",

the I

HELP

I key

is

used to terminate the string. The I

ESC

I key

is

used to return

to

the CONFIG main menu.

3-63

3.

SETTING

THE

CURSOR

AND

THE

FUNCTION

KEY

DISPLAY

If

key 3

is

pressed from the

CONFIG

main menu, the display changes to:

***

CURSOR & FUNCTION

KEY

DISPLAY

***

Select

alphanumeric

or

ESC

to

return.

cursor

tra.cking

cursor

display

cursor

type

on on block,blink

function

key

display:

off

l=on 3=on

5=block,blink

7=underline,blink 9=on

2=off 4=off 6=block,nonblink

B=underline,nonblink

A=off

The

left

of

the

screen shows the current status

of

the various parameters which

can be altered

by

this section

of

the

CONFIG

program. The right

part

of

the

screen shows which keys will change them. The parameter setting

is

altered sim-

ply by pressing the key.

For

example

if

the 9 key

is

pressed, the left

hand

side

of

the screen will change

to

show the function key display

to

be

'on'

and

whenever the

CP

1M

command line

is

displayed, the assignments

to

the func-

tion keys will be shown

on

the base

of

the screen. The display can be switched

off

using the A key

on

this option

of

the

CONFIG

program.

This option also allows the type

of

cursor displayed

to

be changed, by typing

any

of

the keys 5

to

S.

These keys do

not

affect the cursor

on

the command

line

of

the

MENU

and System Display.

Keys 3 and 4 switch the cursor

on

and

off. This affects

both

the cursor

on

the

CP

1M

command line

and

the cursor

on

the

MENU

command line.

Keys 1 and 2 switch the tracking mode

on

and

off. The tracking mode means

that

the cursor follows the window as the real screen moves over the virtual

screen. The non-tracking mode means

that

the window

is

locked

on

a particu-

lar

part

of

the virtual screen

and

the cursor (where input is made,

or

the PX-S prints the next character) will move along the virtual screen, and once it moves outside the window will not be visible. The tracking

and

non-tracking modes

can also be set using the

I

SCRN

I key. Setting the

non

tracking mode with the

CONFIG

program will set the window

at

the

top

of

the screen. The I

SCRN

I

key can be used

to

set the window anywhere

on

the virtual screen.

Futher details

of

using the tracking

and

non

tracking modes are given in

seC-

tion 2.2.6.

NOTE: In the screen mode

3, the type

of

cursor

is

always set to "underline, nonblink"

and cannot be changed with the CONFIG program.

3-64

4.

SETTING

THE

DATE

AND

TIME

Setting the date and time can be achieved by taking option 4

of

the

CONFIG

main menu. The time can be set more accurately

than

in the intialization ques-

tion

when using either

the

sub-CPU

or

initialization reset. The time is entered

the moment the

I

RETURN

I key is pressed. When the date

is

input calculation

of

the day

of

the week

is

carried out automatically.

When option 4 is taken from the

CONFIG

main menu, the display changes to:

***

DATE

& TIME

***

Set

date

and

time

or

ESC

to

return.

Date

as

MM/DD/YY ?

Date Time

00/~~(1/00

(SUN)

18:13:19

Although the PX-S is waiting for the date

to

be input, simply pressing the

I

RETURN

I key will switch

to

asking for the time

to

be input. As soon as the

time option is selected, the time

is

no

longer updated

on

the sixth line. Change

the time by inputting the hours, minutes

and

seconds separated by a colon.

If

any

of

the

data

is

a single digit number, it does

not

have

to

be preceded by

a zero; however,

data

must be input for the hours minutes and seconds

or

an

error will be detected

and

the input line will be cleared. When the correct time

as required has been entered press the

I

RETURN

I key

to

enter it into the memory

of

the computer.

The

time will be updated when the I

RETURN

I key

is

pressed.

If

an

error is made the

00

key can be used

to

erase the characters

to

the

left

of

the cursor.

When the

I

RETURN

I key is pressed after setting the time,

or

directly

on

selecting

option 4 from the

CONFIG

main menu, the date can be input as

month

and

day followed by the last two digits

of

the year, each item being separated by

a backslash

"I"

character. The date will then be entered when the I

RETURN

I

key

is

pressed. The input will then be entered into the memory

of

t.he

PX-S

to

update the date.

If

an

error

is

made, such as trying

to

enter a day

of

the

month

greater then the number

of

days in

that

month, the input line clears

and

awaits a correct input.

When a date has been entered

on

the screen the display changes

to

input a time.

Neither the time

or

date is updated

at

this stage.

To

see

if

the correct date has

been entered, press

I

RETURN

I once more

to

change the input line

to

date input.

3-65

The date will be updated

on

the screen when the time

is

first updated as the

seconds change.

Pressing the !

ESC!

key

at

any time returns

to

the

CONFIG

main menu.

5. ALLOCATION

OF

DISK DRIVES

Selecting option 5

on

the CONFIG main menu will cause the screen

to

change to:

***

DISK DRIVES

***

Select

number

or

ESC

to

return.

disk

drives

: 1

1=

A:

RAM

disk

2=

A: FDDI

3=

A: FDDI

s:

ROMI

B:

RAM

disk

B:

FDD2

C:

ROM2

C:

ROMI

C:

RAM

disk

D:

FDDI

D:

ROM2

D:

ROMI

E:

FDD2

E:

FDD2

E:

ROM2

F:

FDD3

F:

FDD3

F:

FDD3

G: FDD4

This menu makes it possible

to

allocate the logical disk drives

to

the physical

disk drives in one

of

three ways. The three tables

on

the right show the ways

in which the allocations are made. The default drives are set as in table

1.

The

number

to

the right

of

the first colon

on

line two shows which table is selected.

Pressing the

1, 2 or

3 keys will change the selected table,

and

the selected set

will then be shown

on

line 2. The ESC key is used

to

return

to

the

CONFIG

main menu,

and

keys other

than

1,2 3

and

ESC are ignored.

It

is only possible

to

reallocate the drives in these three ways. The Microcas-

sette drive

is

always drive

H:

and so

is

not shown

on

this menu. The terms FDD1,

FDD2, FDD3

and

FDD4 refer

to

additional Floppy Disk Drives which are

connected

to

the PX-8 via the serial interface.

The

ROM drives are shown in

section 4.1.2.

6.

PRINTER

INTERFACING

It

is possible

to

drive a serial printer from either

of

the interface ports. Select-

ing option 6

on

the

CONFIG

main menu changes the display to:

3-66

***

PRINTER .... *

Sel

ect

number

or

ESC

to

return.

printer

ItF

:

RS-232C

1=RS-232C

2=serial

The

fourth

line shows which option

is

selected.

The 1 and

2 keys can be used

to

change the selection. Details

of

using a printer with the PX-8 are given in

Chapter 4.

As with the other sub-menus, after checking which interface

is

selected,

or

chang-

ing the selection,

the!

ESC!

key is used

to

return

to

th~

CONFIG

main menu.

7.

RAM

DISK

This option can be used

to

change the

RAM

disk size

if

part

of

the memory

is being used for file storage.

If

option 7 is taken from the CONFIG main menu the screen display changes to:

***

RAM

DISK

***

Set

RAM

disk

size

or

ESC

to

return.

RAM

disk

size?

RAM

disk

size

: 9

kb

Max.

RAM

disk

size

is

24

kb.

The current RAM disk size is shown

on

the fifth line,

and

can be changed by

typing in the new size.

If

the size is decreased any files already

on

the RAM

disk will be destroyed.

If

the

RAM

disk size is increased the files will remain.

The value

of

the RAM disk size

is

entered into the memory

of

the PX-8 by

pressing !

RETURN

I .

If

the value

is

greater

than

allowed, the input line will be

cleared.

If

the value input is less

than

the current value the fourth line will dis-

play the message:

RAM

disk files will be destroyed

(YIN)

?

followed by a flashing cursor.

If

the Y key is pressed, the new size

RAM

disk

will be set

up,

destroying the files currently saved there.

If

the N key

is

pressed,

the fourth line will clear and place the cursor next

to

the RAM size input message.

3-67

The maximum size the RAM disk can be extended to

is

shown on the right

of

the fifth line. The above display shows the maximum possible

(24

kb) which

occurs when no RAM

is

reserved for USER BIOS.

If

a USER BIOS area has been reserved, the value

of

the maximum value will

reflect this. The total USER BIOS and RAM disk must not exceed 24 kb.

If

an Intelligent RAM disk

is

connected it

is

not

possible

to

use

part

of

the

memory

of

the PX-S

to

extend the size

of

this RAM disk.

For

example,

if

the

RAM Disk Unit

120

is

connected, when option 7

is

chosen from the CONFIG

main menu, the screen changes to show:

***

RAM

DISK ***

An

external

RAM

disk

is

connected.

ESC

to

return.

RAM

di

sk

size

:

120

kb

The ESC key can then be used

to

return

to

the

CONFIG main menu. Further

details

of

the Intelligent RAM disk can be found in Chapter 4.

WARNING: Do

not switch

off

the PX-8 (either manually or

by

allowing the auto power

off

to be activated) after changing the

RAM

disk size without exiting from

the CONFIG program.

Thefull

configuration can only be carried out

by

CP/M.

If

the

PX-8

is

switched

off,

the

RAM

disk could be destroyed

and it may also be necessary to re-initialise the system.

8. CHANGING THE RS-232C INTERFACE PARAMETERS

Option S on the CONFIG main menu allows the settings

of

the RS-232C inter-

face to be set. The RS-232C interface

is

used

to

transmit

data

to

and from the PX-S. For ex-

ample

if

a text file has been written

on

the PX-S and the

data

needs to be used

on

a desk

top

computer such as the EPSON QX-lO, the file can be sent to the

other computer using the TERM

or

FILINK program in the

CP/M

UTILITY

ROM. This transmission can be by cable directly to the other computer, or over a telephone line using

an

acoustic coupler.

The RS-232C interface or the serial interface can be used to connect

to

a printer.

3-68

*'

h·'

h

·1·

f·

d .

h·

_ T e prmter must ave a

sena

mter ace m or er

to

receIve t e mformation.

_

~

This allows program listings as well as letters/reports or other text

data

from

_

I""

applications programs

to

be printed for a permanent record.

~r~

~I~

iJ,r~

~r~

..

,~

-I

e 1

.~

e

I"

e

~

c I

.~

e;

1

.~

e;

I.~

,[---

C

t

___

CL~

~L'4

.,t~

;L~

..

L~

eL~

eL,~

CL~

.~

~

In both these cases the parameters

of

the interface have to be matched. This

option

on

the menu allows the parameters

to

be set. In general they should be

set

or

checked with this option before using the communicatiop.s program (e.g.

TERM or FILINK). Further details

of

the RS-232C interface are given in Chap-

ter

4.

When option S

is

chosen from the CONFIG main menu the screen changes to

display:

***

RS-232C

***

Select

alphanumeric

or

ESC

to

return.

bit

rate : 4800

data

bits:

8

parity

:

none

stop

bits:

2

1=19200 7=300 C=7 E=none H=1

2=9600 8=150

0=8

F=odd

1=2

3=4800 9=110

G=even

4=2400

A=75/1200

5=1200

B=1200/75

6=600

<Tx/Rx)

The bit rate (bits per second

or

baud rate) currently set

is

shown

on

the fourth

line.

It

can be changed

to

various settings using keys 1

to

9 and keys A and

B. The settings produced by keys 1

to

9 set transmission rates in both direc-

tions (transmit and receive). The A and B keys set a rate which is different for

transmitting and receiving. The A key sets

75

baud transmit (Tx) and

1200

receive

(Rx) with the reverse for key B.

The number

of

data

bits

is

shown on the sixth line and can be changed using

the C and D keys.

The parity

is

shown on the seventh line and can be changed using the E, F and

G keys.

The number

of

stop bits

is

shown

on

the eighth line

and

can be changed using

the H and I keys.

When the parameters have been set or checked, the ESC key returns the PX-S

to the main menu.

9. Screen Mode

This option can be used to change the screen configuration. Details

of

the types

3-69

of

screen and its use are given in Chapter 2 (section 2.2.7). There

is

also a detailed

detailed practical guide

to

using the different screen modes in the BASIC Refer-

ence Manual (Chapter 2 section 2.14). When option 9 is chosen from the main

CONFIG

menu, the screen changes to:

*** SCREEN ***

Set

screen

configuration

or

ESC

to

return.

Screen

mode

(O,1,2,3)

?

screen

mode

0

vi

rtual

screen

1

80

i:.

25

virtual

screen

2

80

::{

23

selected

screen

1

separation

character:

The

cursor is located next

to

the

prompt

on

the third line

of

the screen.

The

rest

of

the screen shows the current configuration

of

the screen.

Since different screen modes show

and

require different configurations they

will be treated individually as follows:

Screen

Mode

Il

Pressing the 0 key followed by 1

RETURN

I,

will cause the third line

of

the screen

to

change to:

Number

of

lines

of

virtual screen 1 ?

You can then enter the number

of

lines

of

the screen you require for this screen

in the range 8

to

40.

If

you attempt

to

enter value outside this range, the line

will clear after the

prompt,

and

you can

then

enter a correct value. When the

1

RETURN

1 key is pressed the

prompt

line alters

to

read:

Number

of

lines

of

virtual screen 2 ?

Again the number

of

lines

of

the screen is in the range 8

to

40,

but

the total

of

the number

of

lines

on

the two virtual screens MUST be the less

than

48.

Also each screen must have a minimum

of

eight lines, so the maximum lines

on

a screen is 40

if

the minimum

is

used

on

either screen. When entering a value

for the second screen

if

the

total

of

the two screens would be greater

than

48 with the value you have entered for the second screen, the prompt line will clear so

that

you can enter a correct value. When 1

RETURN

1 is pressed

and

a valid

entry has been made, the

prompt

line will display:

3-70

Select virtual screen (1,2) ?

You can then choose which screen will be displayed.

If

you wish

to

change only one

of

the parameters, simply pressing 1

RETURN

1

will enter the current value. Thus if you only wanted

to

change the virtual screen,

the

1

RETURN

1 key would be pressed until the required

prompt

string was dis-

played.

When the selected screen

is

entered, the display changes

to

show the values

selected.

Since screen mode 0

can

only display one virtual screen

at

a time, the separa-

tion

character parameter will

not

be shown.

Screen

mode

1

In

screen mode

1,

both

virtual screens have the same number

of

lines. Thus

in answer

to

the prompt:

Number

of

lines

of

virtual screen 1 ?

you are in fact choosing the number

of

lines

on

both

virtual screens. Since also

each the virtual screen when displayed

is

split into two columns

of

39

charac-

ters with a separation character, a minimum

of

16

lines is required

on

each vir-

tual screens. Also the maximum number

of

lines

on

each screen is 48.

If

a value

outside the range

16

to

48

to

entered the line will clear from the

prompt

in ord-

er

that

a correct value can be inserted.

When the

1

RETURN

I key has been pressed

and

a correct value has been entered,

the

prompt

line changes to:

Select virtual screen (1,2)

?

One

of

the two virtual screens

can

then be chosen

to

be displayed as split

on

either side

of

the separator. Since the separator is fixed, the screen changes

to

show the changed values.

Screen

mode

2

In

screen mode 2

both

virtual screens are displayed

at

once.

It

is

also possible

3-71

to

alter the number

of

columns

of

the display

of

each screen. The number

of

lines

on

each screen must be the same.

When the number

of

lines in the virtual screens have been chosen correctly in

the range S

to

4S, the

prompt

line changes

to

show:

Number

of

columns

of

virtual screen 1 ?

It

is

thus possible

to

alter the width

of

the two halves

of

the display. The num-

ber

of

columns must be in the range 1

to

79. When the width

of

the left

hand

side

of

the screen is chosen the width

of

the right

hand

side

is

set

to

a value

of

79 minus the size

of

the left

hand

side.

When the screen width has been set the

prompt

line changes to:

Select virtual screen (1,2) ?

and it

is

possible

to

set which screen the cursor lies in. When this has been chosen,

the final input required is the separator character.

If

the I

RETURN

I key is pressed,

the default character is used; this is the same character as

is

used as separator

for the screen mode

1.

On

pressing I

RETURN

I when the separator character has been chosen, the screen

shows all the parameters chosen,

and

it is then possible

to

use the I ESC I key

to

return

to

the

CONFIG

main menu.

Screen

mode

3

There is only one setting for the parameters

of

screen mode 3.

The

screen has

only one virtual screen

of

S lines

and

SO

columns. Thus entering screen mode

3

and

pressing I

RETURN

I causes the

prompt

line

to

revert

to

the same

prompt

line, awaiting either the screen

to

be changed again

or

the I ESC I key

to

be pressed

to

return

to

the main CONFIG menu.

10.

THE

SERIAL INTERFACE

The Serial interface is used for communication with other devices (in particular printers

and

floppy disk drives)

but

not

for general communication in the

way

that

the RS-232C interface is.

If

an

EPSON

disk drive

is

connected, the

transmission rate

is

set by the PX-S.

If

a printer is connected, the transmission

rate can be adjusted using

CONFIG

command.

Selecting option A from the

CONFIG

main menu shows the following display:

3-72

***

SERIAL

***

Select

numbe~

o~

ESC

to

~etu~n.

bit

~ate

(p~inte~)

4800

1=4800

2=600

3=150

bit

~ate

(FDD)

38400

If

a printer

is

being used check

that

the bit rate setting

is

the same otherwise

unintelligible

data

will be printed

on

the printer. Three settings are provided,

and

they can be changed using the

1, 2 and

3 keys.

If

the printer you are using

does

not

have a serial

port

which can be set

to

any

of

these values, you will

only be able

to

print using the RS-232C interface

of

the PX-S, as this has the

standard settings from 19200

to

110

baud. Other protocols are set

to

S-bit, non-

parity, 1 stop-bit. The Floppy Disk Drive bit rate is shown

on

the sixth line for reference.

When the parameters have been set

or

checked, the ESC key returns the PX-S

to

the main menu.

11. USER BIOS SETTING

The USER BIOS

is

used

by

some applications programs.

It

can also be used

by

advanced programmers.

If

you are such a user, please refer

to

the OS Refer-

ence Manual.

An

applications program will normally change the USER BIOS size automatically. The manual which describes the program may tell you to alter the USER BIOS manually in which case follow the instructions given.

Normally the setting

of

the USER BIOS will be 0 pages.

If

you find it

is

not

zero

it

will probably have been set

by

an

application program.

For

example

Portable Scheduler™ uses the USER BIOS area

to

store the alarm times.

If

you change the size

of

the USER BIOS area in this case, the values set up will

no longer be actioned.

<!>

WARNING:

Do

not switch

off

the PX-8 (either manually or by allowing the auto power

off

to be activated) after changing the USER

BIOS

size without exiting

from

the CONFIG program. The full configuration

can

only be carried

out

by

CP/M.

If

the

PX-8

is switched off, the

RAM

disk could be des-

troyed and it may also be necessary to re-initialize the system.

3-73

12.

CHANGING

THE

CHARACTER

SET BY COUNTRY

The

DIP

switch

is

normally used to set the keyboard layout. Occasionally,

it

is

useful to be able to temporarily change the characters

but

not the keyboard layout so that, for example, a word processed file written in French can be read on

the screen with the correct characters. Taking the last option by pressing the key marked C, will enable the character set for the different countries to be displayed. The menu shows:

***

COUNTRY

***

Select

number

or

ESC

to

return.

country

:

ASCII

l=ASCII

2=Denmar-k

3=England 4=France

5=Germany

6=Ital

y 7=Norway B=Spain 9=Sweden

The county whose characters are displayed

is

changed by pressing the key cor-

responding to the country in the table

on

the right

of

the screen. The currently

chosen country

is

displayed on the fourth row on the left hand half

of

the screen.

International Character Sets

S

United

permam

Penmar.

France England Sweden Italy Spain

Norway

Dec. Code

States

35

# #

# £ #

# #

f\

#

36

:$

~

:$

~

64

@

a

§

@

E

@

E

91

[

..

A

[

I[

A

..

i

I[

92

"-

-;

(:)

"-

~

(:)

"-

N

!0!4

93

]

§

u

]

If.

A

E!!

~

If.

94

A

.'-

A A

0

A

.....

0

96

•

e

E!!

u

•

E!!

123

{

E!!

:a

{

~

:a

~

..

:¥!

124

I

U

I

tt-

0.

....

tt-

I

0

I

0

r.

125

)

~

u

)

if

a

~

)

if

126

,."

..

B

,."

u

1

,."

u

3-74

3.9 Communications

The pX-8 can be used

to

communicate with other computers, either directly

or

using telephone lines. This means that program

and

data

files can be sent

from one computer

to

another directly along a simple pair

of

wires - the cables and telephone lines connecting the computers are really no more than this. Connecting a printer to a computer

is

a very simple form

of

communication, as

is

the addition

of

disk drives, so it

is

not really much more complicated to con-

nect another computer. The length

of

the pair

of

wires between the computers

is

irrelevant so long as the correct equipment

is

used.

For

instance,

if

you want

to

connect your PX-8

at

home

to

your QX-lO desktop microcomputer at the

office, all you would need

is

an

acoustic coupler

at

each end into which to plug the telephone handset and the appropriate sending and receiving software to run

on each computer.

It

wouldn't matter

if

one computer was in New York

and the other in London - the system would still work.

The examples given here relate mainly to communication with the EPSON QX-lO desktop microcomputer, the EPSON acoustic coupler

and

EPSON printers,

although any other computers

and

printers may be used given the appropriate

cables and utility software.

HARDWARE When the PX-8

is

required to

'talk'

to other hardware, the following cables

are necessary to connect via the RS232C

I/O

ports:

Cable Type

PX-8

to

PX-8 # 726

QX-lO #725

Acoustic

Coupler

# 724

There are various configurations possible

of

which the following are a few:

~.

#726

..

1 PX-8

Acoustic

Coupler

~.

#725.1

QX-IO

3-75

Acoustic Coupler

#724

PX-8

~

Acoustic

Telephone

Acoustic

I·

#523

..

LJix-lO

Coupler

Line

Coupler

~I

Telephone

Acoustic

I·

..

I Modem

1

#523

Other remote

Coupler

Line

Micro, Mini

or

Mainframe

For

an

explanation

of

RS232C communication see Chapter 4.

SOFTWARE

The two utility programs available

on

the PX-8 are TERM and

FlUNK.

Various other communications programs are available which work in roughly the same way, and you should consult their respective manuals for instructions as

to their use.

3-76

3.9.1.

TERM

The TERM utility

is

used when it

is

necessary to

'talk'

to

a remote computer,

using the PX-8 as a terminal, sending single files in either direction

or

simply

using

both

as

'dumb'

messengers.

In

the following descriptions the second com-

puter

is

assumed to be

an

EPSON

QX-1O (MultiFont

CP/M

version) for the

sake

of

clarity, but equivalent software may be used

on

other machines for this

type

of

communication.

The first thing to do

is

make sure the PX-8

is

connected to the required external devices using the relevant cables, then load the TERM program from the appropriate drive.

When

TERM

is

run

the screen shows the following:

The

RS-232C

status

is

:

bit

rate = 4800

data

bits

= 8

stop

bits

= 2

parity = NONE

Use

CONFIG.COM

program

to

change

the

RS-232C

status.

Modes

of

TERM

1 =

Normal

2 =

Delete

LF

after

CR

(send)/

Insert

LF

after

CR

(receive)

3 =

Insert

ETX

and

Delete

LF

after

CR

(send)

Select a mode

1

The

top

line

of

the screen shows the default RS232C settings (they may not be the same as the ones shown here). These can be changed using the CONFIG program and should be set before running the

TERM

program. Make sure the

receiving computer has the same settings, and change one

or

other machine's

settings so

that

they agree. The three options given

on

the screen refer to how

data

is

sent and received.

i)The default

is

option 1 which merely requires you

to

press the

key, and sets the computer to send and receive

data

without any

modification. This

is

the most commonly used setting.

ii)Some computers automatically add a line feed

to

any carriage return in

the

data

they receive, so in this case you would select Option 2 (delete

LF). This will have the effect

of

deleting line feed codes (ASCII code

10 decimal; hexadecimal

OA)

following carriage returns (hex

OD)

during

transmission,

that

is, when sending data.

It

also adds a line feed code

immediately after any carriage return code in received data. Remember

that

a carriage return merely moves the cursor

to

the beginning

of

a

line - it

is

the line feed code

that

moves it to the next line down.

3-77

iii)Option 3 (add

ETX

and delete LF) has the same effect

on

line feeds as

Option 2, but it also adds

an

'end

of

text' code (ASCII code

03

decimal; hexadecimal 03)

to

each transmitted carriage return after delet-

ing LF code there. When receiving,

data

is

processed as is. This allows

communication with computers which require the ETX code instead

of

the LF code.

When you have selected which mode you wish to use

on

the PX-8 by pressing

[

RETURN

[ key, the screen will display:

Modes

of

TERM

1 =

Normal

2 =

Del

ete

LF

after

CR

(send) I In-sert

LF

after

CR

(recei

vel

3 =

Insert

ETX

and

Delete

LF

after

CR

(send)

Select a mode

1

displayl

printl

sendl

receivel

lexit

The bottom line

of

the screen shows the functions assigned to the

00

keys. When these functions are inactive they appear in lower case characters, and when activated by pressing the relevant key they appear in upper case. These have the following effect:

[§J

- DISPLAY

ON/OFF

This switches the display

ON

or

OFF

while transmission

is

in progress. Nor-

mally, transmitted

data

does not show

on

the PX-8's screen, so switching the

display

on

allows you

to

see what

is

transmitted as it

is

sent.

If

the display

is

switched

on

while

data

is

being received (either from the keyboard

or

from

an

external source) the

data

will show twice

on

the screen. The effect is

that

any-

thing sent from

an

outside source instead

of

appearing

on

the screen as 'Hello'

will appear as 'HHeelllloo'. This would also be the case

if

the display were

switched

on

while using the PX-8 as a terminal.

[

PF2

[ -

PRINTER

ON/OFF

Printer output can be switched

on

or

off

during reception

or

transmission to

produce a

hard

copy

of

the

data

to be transferred. Thus, whatever appears

on

the screen will also appear

on

the printer. Remember

that

because the TERM

program uses the RS232C

port

the printer must be connected

to

the serial port.

The

[PF3 [ and

[PF4

[ assignments

at

the

bottom

of

the screen disappear when

PRINTER

is

ON.

3-78

[

PF3

[ - SEND A

FILE/TERMINATE

TRANSMISSION

A file can be sent

to

the external device and its transmission ended using this

key. This procedure

is

fully described in 1.4 below.

[PF4[

- RECEIVE A

FILE/TERMINATE

RECEPTION

Pressing the

[PF4[

key will make the PX-8

prompt

for the name

of

the file to

be

received. A full description

of

this can be found in 1.3 below.

[PF10[

- EXIT

Pressing

IPF10[ and will cause the PX-8 to exit from the TERM program at any

time.

[

HELP

1-

OUTPUT

BREAK SIGNAL

Pressing the

I

HELP

1 key outputs the BREAK signal

to

the receiving computer.

Note:

When using

TERM

only the junction displayed on the 8th line can be selected.

1.1 SENDING AND RECEIVING MESSAGES When transmitting messages between computers it

is

necessary to have a pro-

gram to handle the

data

being transmitted. Since there are many such programs

and computers, the EPSON QX-IO

is

used as

an

example with the QX-I0 TERM

program as the executing software. First

of

all, execute the

TERM

programs

on

both

the PX-8 and the QX-IO.

The QX-IO screen will show:

QX-IO TERMinal or Remote ver 1.8

rs232c : bit rate

=

31111

parity = no stop bit = 1 data char = 8bit

Terminal mode

.......

1

Remote mode

.........

2

Normal mode

.........

3

change rs232c

........

X

select

1-3

or

X?

Comparison

of

the RS232C parameters with the default parameters

of

TERM

on

the PX-8 will show

that

the handshaking does not match. The quickest way

to

make

an

alteration

is

to change the QX-IO parameters by selecting

'X'.

When

the screen changes to

that

of

fig. below press

'B'

and

'5'

to change the bit rate

to

4800 and the stop bits

to

2:

3-79

QX-IO

TERMinal

or

Remote

ver 1.8

rs232c : bit

rate = 31111

parity

= no

stop

bit = 1

data

char = 8bit

select A-9

or

RETURN

?

bit

rate

parity

stop

bit

data

char

9600

............

A

no

................

0 1..

................

3 0-5bit.

...........

6

4800

.............

B

yes even

........

1 1.5 .. ,

............

4 6bit

..............

7

2400

.............

C yes

odd

.........

2 2

..................

5 7bit

..............

8

1800

............

D

8bit

..............

9

1200

.............

E

900

.............

F

600

............

G

400

............

H

300

..............

I

200

.............

J

151'1

....•••••.... K

135

.............

L

lIe

............

M

75

............

N

51'1

....••••.... 0

The parameters given

on

the PX-8 screen are the default settings, as are those

for the QX-IO. Either computer's settings can be changed using the

CONFIG

command,

but

only the QX-IO's can be changed from within the

TERM

pro-

gram. However, the QX-IO parameters are only temporarily affected

by

the

TERM

program

and

the QX-IO

CONFIG

program must be used

to

alter per-

manently the QX-IO default parameters.

If

it

is

necessary

to

change the

parameters

on

the PX-8 press I

RETURN

I

then

IPF101

(shifted I

PF51

)

to

exit from

TERM. Now you can use

CONFIG

to

alter the parameters.

Now select Option 1 (default)

on

the PX-8

and

Option 1

on

the QX-IO. The

QX-IO's screen will clear

and

the message

3-80

QX-IO Terminal Mode

will appear

at

the

top

with the flashing cursor beneath it. The PX-8's cursor

will move

to

the beginning

of

the line above the function key assignment dis-

play. Typing a message

on

the PX-8 will result in the message appearing

on

the screen

of

the QX-IO.

At

the end

of

a sentence

or

paragraph the I

RETURN

I

key can be pressed which returns the cursor

to

the beginning

of

the same line

and

a line feed can be sent by pressing the [I] key. Exactly the same thing

will happen in reverse

if

you type in a message from the keyboard

of

the QX-IO.

The characters will appear

on

the screen

of

the PX-8 - pressing the I

RETURN

I

key will move the cursor back

to

the beginning

of

the current line

and

pressing

the

[I] key will move the cursor down a line. Pressing

~

on

the PX-8

will

turn

the display

on

and

result in characters input from the PX-8's keyboard

showing

on

both

screens instead

of

just the QX-IO screen. Remember

that

both

computers are completely

'dumb'

in this mode

and

cannot perform any process-

ing. All they

do

is

display

on

their screens whatever has been typed in

on

the

keyboard

of

the other computer.

If

the printer is switched

on

using the I

PF21

key all

output

from the QX-IO key-

board

will be echoed

to

the printer.

WARNING

If

the printer

is

not switched on,

off

line or wrongly connected, the

function key display

of

'PRINT' will flash.

To

exit from this mode press

IPF101

(shifted I

PF51

) on the PX-8 and

the

I

BREAK

I key on the QX-lO.

3-81

1.2

THE

PX-8 AS A TERMINAL

This

is

a very useful function which can be used, among other things, for re-

mote data processing. One instance would be

if

the QX-lO were in the office

and you were in another part

of

the country. You could leave the QX-lO set

up in Remote Mode, plug your PX-8 into

an

acoustic coupler and thence into the public telephone system, then use the QX-lO with the PX-8 behaving as the keyboard and screen. In this way you could enter data, retrieve it and process it from anywhere you happen to be, at any time!

First

of

all, make sure the RS232C settings match (see previous Section). then

run

the TERM program

on

both computers.

On

the QX-IO choose Option 2

to enter the Remote Mode. Wait a few seconds and the

A>

prompt will ap-

pear on the screen

of

the PX-8. This means

that

the PX-8

is

now acting as a

'dumb'

terminal to the host QX-lO computer. You can now use the PX-8 ex-

actly as

if

it were really the QX-IO and perform file manipulation, input and

output, programming

or

any other functions just as though you were using the

QX-IO's own keyboard and screen. The only constraints are

that

the screens

are a different

size

(the PX-8 screen behaves like a window on the QX-lO screen)

and the keys do

not

behave in quite the same way - the

00

key

of

the PX-8

retain their assignments as

part

of

the TERM program,

but

the other keys be-

have as you would expect

on

the QX-IO.

In

fact, the first draft

of

this para-

graph was typed on a PX-8 acting as a terminal

to

a QX-IO which was running

a powerful word processing program!

If

the printer

is

switched

on

with the I PF21 key, all output from the host com-

puter will be printed as hard copy as though you had pressed

@i!!J

-~ .

In

order

to

terminate this host-terminal condition the following operations

on

the PX-8 must be carried out: a) Return

to

the

A>

system prompt given by the QX-lO;

b) Make sure the disk containing the TERM.COM program

is

on

the A:

drive

of

the QX-lO;

c)

Type TERM

to

re-enter the Terminal program;

d) Select Option 3

on

the menu - the QX-lO will now return

to

normal

mode;

e) Press

IPF101

to

exit from the TERM program

on

the PX-8.

3-82

1.3 RECEIVING FILES

Program and data files can be downloaded from an external device to the PX-8 by using the RECEIVE facility. Enter the TERM program in the normal manner, then press

I PF4 I to select RECEIVE. You will then be prompted for a file-

name. This should be the filename you wish the file to have on the PX-8, for instance, to send it

to

the RAM disk call it A:filename.extension

or

to send

it to the microcassette drive call it H:filename.extension. The computer

will

then wait for input from the RS232C port and direct the file to wherever you have specified.

After all the file was received, press

I

PF41

key so

that

the received file may be

closed.

It

is

possible to print the file being received

on

the printer connected to the seri-

al port,

but

not at the same time as it

is

being transferred.

If

PRINTER ON

is

selected the printing will not begin until the file has been fully transferred

to

the PX-S.

If

you are using the QX-lO or another

CP/M

based computer for output, an

easy way

of

demonstrating this

is

to

use the

PIP

command, for instance

A>PIP

PUN: = A:FRED.BAS

This command tells the QX-lO to send the

file

A:

FRED.

BAS

to the device called

PUN:

which

is

the default output device name for the RS-232C port. The

I RETURN I key must

not

be pressed until the PX-8

is

ready and waiting for in-

put.

If

you have told it

to

expect a file called

H:

SALLY .BAS it will receive

the file

A:FRED.BAS

sent by the QX-lO and store it

on

microcassette tape

as H:SALLY.BAS. The contents

of

the file will appear

on

the screen

of

the

PX-S as it

is

transmitted, and transmission can be terminated by pressing the

HELP

key. This outputs a Break signal

to

the transmitting device

and

tells it

to

stop sending.

3-83

1.4 SENDING FILES The PX-8 can send files to an external device by working the opposite way round

to

the procedure for receiving a file.

Enter the TERM program in the normal way, then press

I PF3 I to enter the trans-

mission mode. First the display

of

assignments for keys I PF4 I and I PF2 I are

suppressed, then the prompt

Enter

file name

appears. Type in the complete filename

of

the file you wish to send, e.g.

H:CHARLIE.BAS.

Next comes a series

of

three questions relating

to

time delays to be inserted be-

tween blocks

of

data, as follows:

Enter-

file

name

A:

DOCUMENT.

TXT

Set

transmission

delay

time

in

10

ms

(Max.

255)

After

each

character

0

After-

CR.LF

0

After-

128

bytes

0

The defaults for these delays are 0 milliseconds, i.e. no delay, and this

is

the

most commonly used setting. Consult the manual for the receiving device and

software before deciding

if

these defaults should be altered.

If

you find characters are lost, you can try empirically adding a delay, but in normal circumstances you should not need to change the default values.

At

the receiving end you can

use the same method

as.

described in

1.3

above except

that

this time the RS232C

port should be prepared for input. The command

A>PIP

B:KATE.BAS=RDR:

will read in the PX-8 file H:CHARLIE.BAS through the RS232C

port

of

the

other computer and write it to disk drive

B:

on

that

computer as B:KATE.BAS.

Another possibility

is

that

you may wish to look at a large screenful

of

data.

To

do this you can use the command

A>

PIP

CRT: = RDR:

3-84

which will direct the input

to

the screen.

When

data

transfer

is

completed the TERM program

on

the PX-8 can be exit-

ed in the normal way by pressing the

IPF101

key.

3-85

Error

messages

All errors (except 'Printer not ready', 'File

not

found' and 'File already exists') which require action will necessitate the TERM program being restarted after the error has been dealt with.

a)

PRINT

( I PF2 I key display) blinks -

if

you have selected the printer option

make sure that:

i)

It

is

connected

to

the serial port;

ii) The printer

is

switched on and on-line.

b) RS-232C is not ready - make sure that RS-232C cable

is

connected correctly.

c) File not found - the file you have specified for transmission cannot be found.

You are given the opportunity

to

specify the file again - there was probably

a typing mistake the first time. d) No file name specified - specify the file name e)

Bad File descriptor - specify the correct drive and file name.

f)

Drive select error - you have specified the drive name other than A:

to

H:.

g)

Overwrite (YIN)? - This means

that

the file you have specified already ex-

ists

but

gives you the chance to either overwrite it (by answering Y

to

the

question) or to specify a different filename (by answering N).

3-86

h) Communication error -

if

the RS232C ports

of

the two computers are not

configured with the same parameters the PX-8 will

not

receive recognisable

characters. When data

is

received from the transmitting computer the screen

will show this error message and the prompt:

Press ESC to restart, STOP to exit from TERM

You can then take the appropriate action.

NOTE:

The

QX-IO

TERM

program will cause meaningless characters to appear on

the screen

if

an

attempt is made to send to it with non-matching RS232C

parameters.

i) Directory full - this means

that

the directory

on

the device

to

which you want

the file written

is

full, that is, contains the maximum number

of

entries. You

can delete a file, change the disk or tape

or

specify a different device, and

then start TERM again.

j)

Disk full - this lets you know

that

the device to which you are writing the

file has

no

more space

on

it. In the case

of

a disk

or

a tape change it for

another one with more room

on

it. In the case

of

the RAM disk you will

either have to redirect the file

to

another device

or

risk losing what

is

al-

ready

on

it by expanding it with CONFIG. In any case you will have to start

the TERM program again.

3-87

3.9.2 FILINK

FlUNK

is

a more specialised program

than

TERM

in

that

it supports specific

protocols between machines and is used solely for sending and receiving files.

It

can be used

to

communicate with the following machines using the specified

software:

PX-8

FlUNK.

COM

Portable

WordStar™

using the

'T'

and

'C'

commands

QX-lO

FIUNK.COM

File names

can

be specified in their entirety

or

using wildcard characters

(*

and

?), unlike

TERM

which will only support full filenames.

Refer

to

the OS Reference Manual for details

of

the communications protocol.

The cables used for communication are the same as those specified in Section

3.9.1 for the

TERM

command.

Using

FILINK

When the program

is

run

the following screen appears:

A

file

transfer

program

via

RS-232C

port.

The

RS-232C

status

is

:

bit

~ate

=

4800

data

bits

= 8

stop

bits

= 2

pa~ity

=

NONE

Use

CONFIG.COM

program

to

change

the

RS-232C

status.

Press

ESC

to

restart,

STOP

to

exit

from

FILINK

or

CTRL/STOP

to

abort.

Send

or

Receive

(SIR)?

The second line

of

the screen gives the RS232C settings. These can be changed

using the

CONFIG

program. The fourth

and

fifth lines give information

on

special key usage:

Pressing the

I ESC I key while the program

is

waiting for key

input restarts the program from the beginning. Pressing

I STOP I while the program is waiting for key input stops

the program and returns control

to

CP

1M.

Pressing I

CTRL

I and I

STOP

I together

at

any time results in termi-

nation

of

the program and return

of

control

to

CP

1M.

3-88

The

sixth line describes the wildcard characters allowed when specifying file-

names, and the seventh line asks whether you wish

to

send

or

receive. When

you have typed

in'S'

or

'R'

you will be prompted for a filename. This can

be typed in as a complete name

or

using wildcard characters

(*

and ?). When

receiving files you will have

to

specify a full filename because in this case you

are actually specifying the file into which the

data

being received

is

to

be put.

When sending files, a whole family

of

files can be sent using the wildcard op-

tions, for instance

D:*.BAS

will ensure

that

all files

on

drive D: having the extension BAS are sent down

the line.

Error

messages

a) Directory full -this means

that

the directory

on

the device

to

which you want

the file written

is

full, that is, contains the maximum number

of

entries. You

can delete a file, change the disk

or

tape

or

specify a different device,

and

then start

FlUNK

again.

b) Disk full - this lets you know

that

the device

to

which you are writing the

file has no more space

on

it.

In

the case

of

a disk

or

a tape change it for

another one with more

room

on

it.

In

the case

of

the

RAM

disk you will

either have

to

redirect the file

to

another device

or

risk losing what

is

al-

ready

on

it

by

expanding it with CONFIG.

In

any case you will have

to

start

the

FlUNK

program again.

c) Overwrite (YIN)? - This means

that

the file you have specified already ex-

ists

but

gives you the chance

to

either overwrite it (by answering Y

to

the

question)

or

to

specify a different filename (by answering N).

d) File not found -the file you have specified for transmission cannot be found.

You are given the opportunity

to

specify the file again - there was probably

a typing mistake the first time.

e) Receiver is

not

ready - make sure you have connected the PX-8 correctly

to

the external device and

that

the receiving computer is ready

to

receive

the file.

f)

No file name specified - Specify the file name.

3-89

g)

Bad file descriptor - Specify the correct file name.

h)

Drive select error - Specify the drive name from A: to

H:.

i)

Communication error -

if

the RS-232C ports

of

the two computers are not

configured with the same parameters the PX-8 will not receive recognisable

characters. When data

is

received from the transmitting computer the screen

will show this error message and the prompt:

Press ESC to restart,

STOP

to exit from FILINK

You can then take the appropriate action.

NOTE:

The QX-10

TERM

program will cause meaningless characters to appear on

the screen

if

an

attempt

is

made to send to it with non-matching RS-232C

parameters.

j)

Close error - replace the new disk and restart from the beginning.

k) Sender is

not

ready - make sure

that

the sending computer

is

ready to send

the file.

I)

RS-232C is not ready - make sure

that

RS-232C cable

is

connected correctly.

3-90

3.10 Other

CP

1M

Transient Programs

Apart

from the utility programs

or

commands in

CP

1M

which have already

been described, there are some others which will be available

to

you as soon as you connect a disk drive to your PX-8. Some are disk utility programs and some allow you to carry

out

all sorts

of

operations

on

the computer which are

either difficult

or

impossible with the machine

on

its own. Please consult your

dealer for information

on

obtaining these programs.

1. Disk utilities

a)

FORMAT

(Preparing a floppy disk for use)

This program allows you

to

FORMAT

a floppy disk in a specified drive. FOR-

MATting

is

a process whereby the disk

is

divided up into sections which help

the computer to find its way around.

It

also has the effect

of

erasing all the

data

already

on

the disk. This function may be included in COPYDISK.

b) COPYDISK (Making

an

exact copy

of

a floppy disk)

Instead

of

using

PIP

you can use COPYDISK

to

copy the entire contents

of

one disk

on

to

another. This

is

particularly useful when making back-up copies

of

program and

data

disks. This program incorporates a VERIFY facility so

that

it compares what

is

on

the disk from which you are copying with what

is

being written

to

the disk

on

which the copy

is

being made, thus ensuring a

perfect copy.

2.

Program

utilities

a)

ED

(Editing a file)

This

is

an

EDitor incorporating a powerful set

of

sub commands which can be

used for on-screen creation and editing

of

files.

It

is

most useful when creating

SUBMIT files

or

when typing in

or

correcting assembler programs.

b)

DDT

(Dynamic Debugging Tool)

Programs written in Intel 8080 in assembler

or

machine code can be quickly

debugged

or

altered with DDT.

It

contains a number

of

subcommands which

can be used to look at, alter

and

assemble programs in memory. Files changed

in this way can be written back to disk using the

CP

1M

SAVE command.

3-91

c)

ASM (8080 Assembler)

When

an

assembler program has been written and given the filename extension . ASM, running this program will assemble it and produce object and list files with the filename extension

.HEX

and

.PRN

which are automatically written

to disk.

d) LOAD (Producing COM files) When an assembler program has been assembled using the ASM program, the

object code file (type .HEX) can be converted into

an

executable machine code

file with the filename extension .COM. You can use this to create your own

commands

on

disk.

e)

DUMP

(Hexadecimal file dump)

Any file

on

a disk can be shown

on

the screen in hexadecimal form using this

program. Each line contains a 16-byte section

of

the file with the starting ad-

dress given

at

the left hand end.

3-92

"'l'

,-

"'7'

"...,

'f'

~~

,,,

.~

.'"

~T

,-."

.

..,

~~

.,

~

-~

'"

--'

.~

~

3.11 Finding

Out

More

About

CP/M

This manual cannot cover all aspects

of

using

CP/M

particularly the finer points .

The following books are among many available from your computer dealer

or

bookshop.

CP

/M

and the Personal Computer by Thos

A.

Dwyer and Margot Critchfield.

This covers

CP/M

from the beginners point

of

view as well as containing much

information

on

the internal workings

of

CP/M

and advanced uses. (Published

by Addison Wesley. ISBN 0-201-10355-9)

CP/M

Handbook

by Rodney Zaks. This

is

a general guide

to

using

CP/M.

(Published by Sybex. ISBN 089588-048-2)

Osborne

CP/M

User Guide by Thorn Hogan. Another general guide. (Pub-

lished by Osborne/McGraw Hill)

CP

/M

BIBLE -The Authorative Reference Guide

to

CP/M

by Mitchell Waite

and

John

Anglermeyer. As the title suggests, a reference guide

to

the use

of

CP/M.

(Published by Howard Sams. ISBN 0-672-22015-6)

Soul

of

CP/M

by Mitchell Waite and Robert Lafore. This

is

a guide for the

advanced user and programmer. (Published by Howard Sams. ISBN 0-672-22030-X)

CP

/M

The Software Bus - A Programmers Companion by A.Clarke, J .M.Ea-

ton

and D.Powys-Lybbe. A further manual for advanced programmers. (Pub-

lished by Sigma Technical Press. ISBN 0905104-18-8)

3-93

Chapter 4

INPUT

AND

OUTPUT

DEVICES

AND

OPTIONAL ADDITIONS TO

THE PX-8

INTRODUCTION

This chapter deals with the aspects

of

the PX-S involved with interfacing the

computer to other devices. Some

of

the devices are

an

integral part

of

the PX-S,

others can be purchased separately. Epson

is

continually developing further

products and so this manual cannot cover every device it is possible

to

use with

your PX-S. This manual does not mention specific products

as

in most cases

these items vary from country

to

country. You should consult your dealer for

the products available in your country and for details

of

new optional items.

4.1 Storage

of

Files and Data

The PX-S has many means

of

storing files. There are also ROM capsules

on

which manufacturers

of

applications programs can provide their programs. These can be read but not used for storing files. The other important method of

storing data

is

the Microcassette drive.

It

is

also possible

to

add

on

floppy

disk drives.

4.1.1 Microcassette Drive

The PX-S

is

equipped with a built in Microcassette drive. This section describes

operation

of

the drive.

a)

Drive name

The microcassette drive can be used in the same manner as other disk devices.

It

is

assigned drive name

H:.

It

is

not possible

to

assign drive name H:

to

any

other drive, nor

to

assign any other drive name

to

the Microcassette unit.

Be-

cause a cassette tape functions differently from a floppy disk, a special operat-

4-1

ing system has been added to the PX-8

CP

1M.

This

is

known as MTOS

(Microcassette Tape Operating System).

It

means

that

CP

1M

can use the

microcassette drive as the equivalent

of

a disk drive. Because

of

the physical

differences in operation the use

of

a microcassette

is

slightly different from us-

ing a floppy disk

or

RAM disk. This

will

become obvious as you study the oper-

ation

of

the Microcassette drive.

b) Microcassette selection and use Consult your Epson dealer for supplies

of

microcassette tapes.

You should ensure

that

the tapes you buy are

of

the correct type as there are

similar

size

cassettes which are not compatible with the PX-8 Microcassette drive.

Microcassettes are available in sixty-minute lengths (thirty minutes per side) and thirty-minute lengths (fifteen minutes per side). These are marked MC-60 and MC-30 respectively. Because a thirty-minute tape will store

10K

to

SOK

bytes

of

information per side, it

is

usually adequate for storage

of

your most fre-

quently used

data

and programs.

It

is

recommended

that

you use the shorter

tapes because it

is

often faster

to

change tapes (or flip one over)

than

to wind

to the end

of

a long one. In addition, shorter tapes are less likely

to

jam.

The

microcassette directory can only hold

12

file names, so

12

short

data

files

or

programs will leave a long length

of

unusable blank tape.

Some

of

your most important

data

will be saved

on

microcassettes, so it

is

im-

portant to care for them properly.

To

keep the tape clean, always keep it in

its protective case when it

is

not in use. Never let your fingers touch the tape

itself; the oil from your skin can contaminate it.

Be

sure

to

keep your tapes away from magnetic surfaces. Proximity to a magnetic field can erase your tapes. Magnetic fields are found in television sets and other devices

that

have trans-

formers

or

speakers. Dirty recording heads in your microcassette drive can cause errors in reading and writing and can even damage your tapes. You should clean them periodically, using a head-cleaning cassette, a cleaning kit (available where you purchase your cassettes)

or

a cotton swab and isopropyl alcohol.

c)

Tape Insertion

To insert the Microcassette tape proceed as follows:

4-2

1) Press the

EJECT

key to open the microcassette compartment cover.

I1111

MICRO

CASSETTE

/' V

)(

(~/\I

fh~Y:/)

!/~

)1

REC

,g'~

c:::J

EJECT

~

§]

Fig.

4.1

2)

Insert a microcassette with the side to be used uppermost. This will have the majority

of

the tape as seen through the window

on

the right

hand

side.

Fig.

4.2

4-3

3)

Close the microcassette compartment cover.

Fig.

4.3

d)

Manual operation

The microcassette drive can be operated manually by using the System Display.

3)

Place the PX-8 in the System Display mode by pressing the 1

HELP

I key

together with the

1

CTRL

1 key.

***

SYSTEM

DISPLAY ***

<RAM

DISK)

009

kb

<USER

BIOS)

000

256

b

<MENU

DRIVE>

CBA

00/00/00

(SUN)

19,58,35

<MENU)

(AUTO

START>

(MCT

MODE>

stop,

nonver-ify

<COUNT>

65535

(MENU

FILE> 1 .COM

2 .BAS

3.

4

-

Select

number

or- ESC

to

exit

..

l=password

2=alarm/wake

3=auto

start

4=menu

5=MCT

«-

I

<-

Imount

fi

Idir-init

-»

ler-ase

0001

Fig.

4.4

The bottom line

of

the System Display can show two states depending on whether a tape has already been set up or 'MOUNTed' in the drive. Section 4.1.1(f) describes this in detail, but for now it

is

sufficient to say that because a cassette

tape accesses data sequentially along the

tape

and the directory

is

storeg at the

beginning, it

is

not practical to write the new directory to tape each time a pro-

gram

is

saved. Consequently it might be possible

to

change tapes without updating the directory, and the MTOS would not be able to find a file or program. There

is

a safeguard built in to prevent this.

It

is

not possible to move along

a tape

if

the MTOS

is

in control

of

the tape.

If

a tape

is

MOUNTed then the

bottom line

of

the system display will show:

remove/

4-4

REMOVal and MOUNTing

of

the tape

is

described in section 4.1.5f.

If

the display shows REMOVE and you wish to continue with this explanation, press the SHIFT key and function key PF1, then wait until the display shows the

bottom line:

«-I

<-

Imount

./dirinit

-»

lerase

0001

The bottom line shows the microcassette drive functions assigned to the programmable function keys.

1

PF1

I:

Fastforward

1 PF21: Play

1 PF7

I:

(

'I

"'-::S::-:H=IFT=---I

and 1

PF2

I ) mount

1 PF3 I: Stop denoted by the m character

1 PF8

I:

(I

SHIFT

I and I

PF3

I ) dirinit

I PF4 I: Rewind I PF9 I:

(I

SHIFT

I and I PF4 I ) erase

I

PF5

I: Counter reset

These are best understood by following an actual operation.

1)

Insert a blank microcassette. Look at the tape counter setting in the [COUNT] field

on

the 4th line

of

the System Display. The counter may be 00000.

If

not, press the I PF5 I key

to

reset it.

2) Press the

[fIT]

key and the tape

will

move forward rapidly. Press the 1

PF31

key and the tape will stop. Look

at

the tape counter. The value will indicate

that the tape has moved.

3)

Press the

[PF4J

key and the tape will be rewound. The tape automatically

stops when the end

of

tape

is

reached. The count should then be 00000.

4)

Press the 1

PF21

key and the tape will move forward slowly.

If

something

is

recorded

on

the tape, sound

is

produced from the speaker. You will not

hear this unless the volume

is

turned up.

It

is

not possible to record sound

using the PX-8 but

it

can play back audio tapes. The tape count increases

as the tape moves.

5)

If

the tape contaihs files, they can be erased by pressing the 1

PF4

I and

1

SHIFT

I keys simultaneously. This

is

primarily intended for erasing audi-

ble sound.

4-5

6)

Rewind the tape and press the

EJECT

button

to remove the micro cassette

from the drive.

When you have familiarised yourself with the controls you can now use the other controls

on

the function keys to prepare a tape on which to store

programs.

e)

Directory initialization (DIRINIT)

The tape directory

is

a tape block which contains various information required

for the microcassette tape operating system to manage tape files. This infor-

mation includes the number

of

files in the tape, the tape location

of

each file

(the tape count

at

the beginning and end

of

the file), the name

of

each file,

etc. The tape directory

is

always placed

at

the beginning

of

a microcassette tape.

Although the operating system manages the tape directory, you must initialize the directory block

on

to the tape before using a new tape. The procedure to

do this

is

as follows:

1)

Load a new microcassette.

2)

Place the PX-8 in the System Display mode by pressing the

I

HELP

I

key

together with the

I

CTRL

I

key.

**

.•

SYSTEM

DISPLAY

***

00/00/00

(SUN)

19:58:35

(MENU)

<AUTO

START>

(RAM

DISK)

009

kb

(USER

BIOS)

000

256

b

<MENU

DRIVE>

CBA

<MCT

MODE)

stop,

ndnverify

<COUNT>

65535

(MENU

FILE)

1

.COM

2 .BAS

3.

4

-

Sel

ect

number

or

ESC

to

e~<

it.

l=password

2=alarm/wake

3=auto

start

4=menu

5=MCT

«-

/

(-

/mount

•

/dirinit

-»

/erase

000/

Fig.

4.5

3)

Press the

I

PF31

key together with the

I

SHIFT

'key. The screen will clear and

the message

"dirinit"

will appear on the display. The tape will start and the

REC lamp light.

4)

When the directory space has been written to the tape, the REC lamp goes off

and the display changes back to the System Display,

but

now the bot-

tom

line

is

different:

4-6

***

SYSTEM

DISPLAY

***

00/00/00

(SUN)

23:37:47

<MENU>

<RAM

DISK>

009

kb

<AUTO

START)

<USER

BIOS>

000

256

b

<MCT

MODE)

stop,

nonverify

<COUNT>

00189

<MENU

DRIVE>

CBA

<MENU

FILE>

1

.COM

2

.BAS

3.

4 .

-

Select

number

or

ESC

to

exit.

l=password

2=alarm/wake

3=auto

start

4=menu

5=MCT

Iremove

I I I I

Fig.

4.6

5)

The tape can be used immediately, that is, it

is

already MOUNTed ready

for use. The function key assignments have been changed and you can only REMOVE the tape. This prevents another tape being MOUNTed. MOUNTing

is

explained in the next section.

If

you do

not

wish to use the tape, press the

I

ESC

I

key

to

exit to the state

in which you were before you pressed the

I

CTRL'

and

I

HELP'

keys.

f)

Preparing Microcassette tapes for use - MOUNT

and

REMOVE

Since the tape behaves as

if

it were a disk, the directory

is

written to the tape

in the same way as on a disk. However,

if

the tape directory were read each

time a tape file was accessed, it would take a relatively long time to rewind the tape

to

the tape directory and then rewind

to

the file location. To overcome

this, the contents

of

the tape directory are stored in RAM. The process

of

load-

ing the directory into RAM ready

f.or

saving and loading from the Microcas-

sette tape

is

known as MOUNTing the tape. This can be achieved in a number

of

ways:

Manually

i)

By

pressing the

I

PF2 ,

and

I

SHIFT

I

keys simultaneously in the System

Display

ii)

By

executing the MOUNT statement in BASIC, in direct mode.

Automatically

i)

By

using the DIR H: command in

CP

1M,

if the tape has not been mounted.

ii)

By

logging into drive H: from the

CP

1M

command line

if

the tape has

not

been mounted.

iii)

By

saving a file

to

a tape which has not been mounted.

iv) By executing a command which loads a file

or

data from the Microcas-

sette

if

the tape has

not

been mounted.

v)

By

exiting from a program when the tape has been REMOVEd,

if

the cur-

rently logged in drive

is

drive

H:.

vi) By using the MOUNT command in a BASIC program line.

4-7

The contents

of

the directory stored in RAM (RAM directory) are accessed each

time a tape file

is

read from

or

written to, that is the directory

is

updated in

RAM. This means that the contents

of

the tape directory must be replaced with

the contents

of

the RAM directory before removing the tape, otherwise it would

not be possible to access the files.

The tape can be REMOVEd by one

of

the following methods:

i)

By

pressing the

~

and I

SHIFT

I keys simultaneously in the System

Display mode .

ii)

By

executing the REMOVE statement in BASIC.

Because

of

the danger

of

replacing tapes

or

mounting them when another

is already mounted, the System Display will not allow any operation other than removing a tape, once a tape has been mounted.

IMPORTANT: It

is best to get into the habit

of

checking whether a tape is mounted or not.

AL

WA YS press

CTRL

and

HELP

to check the status

of

the tape before

REMOVAL

or

INSERTION

of

a new tape. This

is

especjally important since

the tape could have been MOUNTed without you remembering having done so,

for

instance

by

a DIR

access.

<!>

WARNING:

If

you change a tape without executing the

REMOVE

statement in BAS-

IC

or using the

REMOVE

on the System Display, you will not only

des-

troy data on the new tape, but you will also destroy data on the old tape.

When you REMOVE a tape either in BASIC

or

through the System Display,

the following will occur:

1)

If

the tape has only been read,

or

the directory simply loaded into RAM:

i)

If

the REMOVE was executed from the System Display, the screen will

clear for a moment and the word

"remove"

displayed briefly. The dis-

play will then change back

to

the System Display.

ii)

If

the REMOVE was executed from the BASIC command line, the cur-

sor will simply return after printing

"Ok".

iii)

If

the REMOVE was executed from a BASIC program, it will continue

from the next line.

4-8

iv)

The EJECT button can then be pressed and the tape removed or replaced. The directory will not be written to the tape, in any

of

these cases.

2)

If

a file has been written to the tape, deleted or renamed, or the file new

attribute

is

set, the directory has

to

be rewritten.

i)

The tape will rewind.

ii)

If

REMOVE was executed from the System Display, the screen will clear

and then display the word

"remove" to

show that the tape

is

being re-

moved.

If

the REMOVE was executed from BASIC the cursor will disap-

pear (if the command was issued from the command line) or the program

will wait for the directory to be rewritten.

iii) The REC light will go

on

and the directory in RAM will be written onto

the tape.

iv) When the directory has been written back to the tape, the REC light will

be extinguished. The System Display will return

if

that

is

where the RE-

MOVE

was

initiated.

If

the BASIC command 'REMOVE'

was

used, either

the cursor will return

if

REMOVE was executed from the command line

or

it will continue with the next line

of

the program. '

v)

The EJECT button can then be pressed and the tape removed or replaced.

g)

Checking

if

the tape is mounted.

If

you need to know

if

the tape

is

mounted, press the I CTRL I key together with

the

I HELP I key

to

show the System Display. Look

at

the bottom line.

If

it

says:

/remove

this indicates that the tape directory has been mounted. You can use

I

ESC

I to

return

to

whatever else you were doing,

or

press the I

SHIFT

I and

[fill

key

to

REMOVE the tape.

h) Using software with the Microcassette drive The microcassette drive can be used in the same manner as a disk device. The drive name H:

is

assigned to the microcassette drive.

1)

Obtaining a directory

of

the Microcassette tape

Type DIR H: in the

CP/M

operating mode (that is, when the system prompt

A>

is

displayed). The tape directory

is

automatically accessed and the names

of

all files recorded

on

the tape are listed

on

the screen as shown below.

4-9

A>OIR H:

H:

SAMPLE!

BAS

SAMPLE2

BAS

A>

Fig.

4.7

ii)

Executing a program from the Microcassette Drive.

The microcassette drive

is

used in exactly the same way as any other drive. Since

the Microcassette drive

is

drive H:,

to

run the program

"PROG.COM"

from

the Microcassette drive type the following

on

the

CP

1M command line:

A>H:PROG

iii)

BASIC

and the Microcassette Drive.

The BASIC statements and functions concerned with the microcassette drive are as follows.

EOF GET INPUT

#

INPUTS LINE

INPUT

#

LIST LOAD LOF LOC LSET/RSET MOUNT

OPEN POS PRINT

#

PRINT

USING # PUT REMOVE SAVE TAPCNT WIND WRITE

For details

of

these statements and functions, refer to the PX-8 BASIC Refer-

ence Manual.

Note that the DSKF function does not return meaningful values with the Microcassette drive.

i)

The Stop and Non-Stop Mode

and

Verification

Tape storage

is

different from a conventional floppy disk, in that the

data

is

saved sequentially.

On

a floppy disk

if

there

is

a read error it

is

possible

to

go

4-10

back to the area on the disk which was . mis-read and

try

again.

On

a tape this

is

not

possible unless the tape

is

rewound, which

is

not a practical proposition.

The data

is

thus stored twice

on

the tape, so

that

if

an error in reading occurs

there

is

chance for another attempt. Another problem with tape access which

does not occur on a floppy disk,

is

that frequently the tape can go past a block

of

data

because the tape did

not

stop in time when the previous block was read.

These problems can be overcome by frequent stopping and starting

of

the tape, both when reading and writing. The System Display allows two different modes of

reading and writing the data, the Stop and Non-Stop modes. See section

2.2.3.e. for how to set the Stop and Non-Stop modes.

By

stopping the Microcas-

sette drive frequently the

data

can be placed

on

the tape more accurately when

writing and will allow more accurate reading also.

When

data

is

written to the tape, the following sequence occurs. A short length

of

the tape

is

erased then a header block

is

written. This contains information

such as the name

of

the file and its type, and various data dealing with the length

of

the file, the tape counter etc. Then the

data

is

written in blocks

of

256 bytes

each block

of

data being duplicated. Finally the data

is

followed by an end

of

file marker.

If

the Stop mode

is

set, the microcassette drive stops between each

block as it

is

written.

If

Non-Stop mode

is

used when the

data

is

written, the

data

is

written without stopping.

<WRITE>

256

bytes

each

T T

1.--..1.--,1

L...I

--1..---11

mW%@a

Seek

Erase

Header

Block1

Block2

Block3

EOF

Erase

t:;.

Fig.

4.8

..

Stop

in

Stop

mode

"

Stop

in

Non-stop

mode

4-11

When

data

is

read from the tape

if

Stop mode

is

set the tape again stops be-

tween each block

of

data

before the next block

is

read.

If

Non-Stop mode

is

set, the

data

is

read consecutively. Unless otherwise set, the data

is

read in the

same mode it was written in.

<READ>

256

bytes each

T T T T

Block2 Block3

EOF

Seek

..

Stop

in

Stop

mode

Fig.

4.9

'"

Stop

in Non-stop mode

In reading and writing files using the STOP mode this has the following effects:

i)

More tape

is

used when the Stop mode

is

used

to

write a file.

ii) The file takes longer

to

write.

iii) When reading a tape written in the Stop mode, more accurate reading

is

possible.

iv) In extreme cases errors can occur in reading files written in Non-Stop

mode. This

is

most likely

to

happen when reading single records from a

file as this requires the Microcassette drive

to

be stopped and started by the program. When the tape stops under program control it cannot always stop in the correct position in front

of

the next record. Thus it can

miss the record or part

of

it and generate an error. This can be overcome

by reading the record in Stop mode. As further security against this

errOl:

occurring read and write such files in Stop mode, by setting the STOP

mode from the System Display before running the program.

4-12

j)

The Verify and Non-Verify Mode

In

order to ensure accurate recording

of

data

on

a Microcassette tape, it

is

pos-

sible to have the

data

checked by specifying the Verify mode when the

data

is

written. The Verify mode

is

switched on and

off

from the System Display,

(see section 2.2.3.e). In

the verify mode, each 256-byte block

is

verified after the entire file has been

written

to

the tape.

If

an

error

is

detected, one

of

the following messages

is

displayed.

BDOS

ERROR

ON

H:

BAD SECTOR

Disk Read error

(under

CP/M)

(under BASIC)

In

the Non-verify mode, files written

to

tape are

not

verified.

It

is

recommended

that

the verify mode be used when writing files

to

cassette

tape. When a file

is

written, the Microcassette drive will carry out the following

procedure:

i)

The tape will be wound

to

the next available position. Sometimes it may

rewind to the beginning

of

the tape and then wind on so

that

it can be

sure to be

at

the correct position.

ii) The REC light will come on and the file will then be written

to

the tape.

The tape may stop

and

start

if

the Stop mode

is

set.

iii) The REC light will go out.

iv)

If

Verify

is

set, the tape will be rewound

to

the start

of

the file and the

file will be checked.

v)

The tape will stop

and

the

EJECT

button

will be unlocked.

Verify does not operate when reading tapes.

k) Rules for day to day use

of

the Microcassette Drive.

1)

Always check

that

a tape has been REMOVEd before taking it out

of

the

drive, otherwise the directory will not be written back

to

the tape,

and

could

be written

to

another tape.

2)

Never use DIRINIT without checking the directory

of

a tape

if

it

is

not a

new one.

3)

Never switch

off

while a file

is

being recorded

or

read. The file will not be

appear

on

the directory

if

the power

is

switched

off

manually while record-

ing

is

taking place.

4-13

SUMMARY

OF

MICROCASSETTE DRIVE

OPERATION

System Display mode

Execution in BASIC

Function

Display

Operation

mount

SHIFT + PF2

MOUNT Reads the tape directory

remove

SHIFT + PFI

REMOVE Writes the tape directory

dirinit

SHIFT

+ PF3 Initializes the tape directory

«-

PFI

WINDn

Tape

Fast forwrd

-»

PF4

WINDn

Rewinds the tape

<-

PF2

Plays the tape through the speaker

erase

SHIFT + PF4

Erases the contents

of

the tape

•

PF3 Stops the tape

000 PF5

TAPCNT=O

Ressets the tape counter

to

zero

4-14

4.1.2 ROM capsules

Many computers are able

to

plug in programs which are then instantly able

to

be run. The PX-S has a slight variation

on

this concept. The programs are sup-

plied in a

ROM

which is similar

to

the program cartridge,

but

is used by the

PX-S operating system as

if

it were a disk drive. There are two ROM sockets

in the base

of

the PX-8 which contain the BASIC language and a number

of

CP

1M

Utility programs, when you purchase the PX-S.

If

you have been sup-

plied with other programs in ROM you can change them as follows.

a) Changing

ROM

capsules

1)

First check with the applications program manual

that

no special instruc-

tions are given for changing ROMs. This

is

only likely

to

occur

if

the pro-

gram requires more

than

one ROM for operation.

An

example

of

this is

given below.

2)

Carry

out

whatever operations are necessary

to

return

to

the MENU

or

to

the

CP

1M

command line.

3)

Switch the power

off

usin~

the power switch.

Fig. 4.10

4-15

4)

Remove the ROM compartment cover as shown below and lift the silver coloured flap. The two ROMs lie side by side and are held in a carrier.

Fig.4.11a

Carrier

Fig.4.11b

4-16

5)

Remove one

of

the the ROM capsules indicated by the arrows by lifting

the tabs

at

the top and base

of

the ROM. Do not use excessive force

SW4

:!

II

~SW5

c

~

ROM

2 ROM 1

Fig.4.12a

6)

Now take the ROM capsule you wish

to

insert into the PX-S. The plastic

carrier has two tabs. Hold it so that the tab with two holes

is

towards the

back

of

the PX-S. Then place the carrier over the ROM socket so that it

sits loosely in the socket. The carrier and socket are made like a key and a lock.

It

is

only possible

to

fit the carrier into the socket the correct way.

Now gently push the ROM and plastic carrier so that they fit level with the top

of

the socket. Use two fingers, one

at

the top and one

at

the bot-

tom, to ensure even pressure.

Fig.4.12b

4-17

7)

Finally return the silver coloured flap to its original position and replace

the outer plastic cover.

8)

Turn the power back on.

9)

If

you are on the MENU page, press the 1 ESC 1 key to go

to

the

CP

1M

com-

mand line. From the

CP

1M

command line carry out a warm boot by press-

ing

1

CTRL

1-

[g

or the 1

STOP

1 key.

10)

The programs can be loaded from drive

B:

if

the ROM has been placed

in ROM socket

1,

and from drive C:

if

placed into ROM socket 2. The

assignment

of

the sockets to different drives, can be changed using the CON-

FIG

program described in Chapter

3.

<!>

WARNING:

. Only pick up the

ROM

by the plastic

carrier.

Do not touch the metal

pins

of

the

ROM

with

your fingers. This

can

cause

the pins to

cor-

rode,

and could

also

destroy the program contained

in

the ROM.

b) Using the ROM as a disk to contain data

or

BASIC programs.

Some application programs may use data which

is

provided in ROM form. The

manual which comes with the program will describe how

to

use this data. The

program will have a command

or

specifically prompt you

to

change the ROM.

Alternatively the manual may tell you

to

change the ROM in order to run the

BASIC program.

If

the program

is

a BASIC program you can use it from ROM

as follows:

1)

When you have loaded BASIC, switch the computer

off

in the continue

mode by switching the power

off

while pressing the 1

CTRL

I key.

2) Remove the BASIC ROM, and insert the program ROM as in steps 4 to 7

of

the description

of

changing the ROM.

3)

Switch the power back on.

4) From the BASIC command line type the RESET command followed by the

[RffiTFfN]

key.

5)

You can now load the program

or

data from the ROM, treating it as any

other drive.

4-18

4.1.3

RAM

Disk Unit - additional

RAM

disks

Previous chapters have described the use

of

part

of

the memory area

to

store

programs. This

is

referred to as the RAM disk. The size

of

RAM disk in the

main memory

is

at

most

24K

bytes.

If

your applications require more memory

space,

an

optional RAM disk unit

of

larger capacity can be connected to the

system bus connector. This

is

known as an Intelligent RAM disk

Two types

of

optional RAM disk units are available: one

is

of

60K

bytes (Model

HI02A) and the other

is

of

120K bytes (Model HI03A). (These units actually

contain

64K

and

128K

of

RAM. However, some RAM

is

used by the firmware

so

is

not all available to the user.)

When an Intelligent RAM disk unit

is

connected, the internal RAM disk can-

not be used. When fitting an additional RAM Disk Unit the PX-8 must be in-

itialized, and the disk formatted in the same way as the RAM disk which uses

part

of

the internal memory. When initializing either pressing a

7508

(sub-CPU)

reset switch or using the

I

SHIFT

1-

IG~~~lkeys

while pressing the reset button,

the PX-8 will know that an external disk

is

connected. There

will

be no request

for the size

of

the RAM disk,

but

it will still be necessary to format the disk.

If

you try to write to the RAM disk when the write protection switch

is

on,

a BDOS error messaage will be displayed

on

the screen.

4-19

CP

1M

manages the organisation

of

saving

and

loading programs to the RAM

disk, just like any other disk, with the following additional features:

i) Input

and

output speed

is

much higher

than

other disk devices even ordi-

nary floppy disk drives.

ii) The PX-S

is

very little larger in

size

and weight than without the disk added.

iii) The Intelligent RAM disk can be write protected with a switch and so per-

manently protected.

Apart

from having more available memory, the Intelligent RAM Disk Unit

is

used in exactly the same way as the normal RAM disk.

It

cannot be changed

in size, nor can any

of

the PX-S RAM be used

if

the Intelligent RAM disk

is attached. Thus when initializing with an Intelligent RAM Disk connected, no message will come up asking for the size

of

the RAM disk. You will be asked

whether it should be formatted however.

When an Intelligent RAM Disk Unit

is

fitted, a check

of

the contents

is

made

each time on power up, to ensure the

data

is intact. This only occurs

if

DIP

switch

4-5

is

set to ON.

If

the

data

is

corrupted, the screen will clear and a mes-

sage will appear to ask

if

you wish the RAM Disk to be formatted. The check

takes eight seconds.

If

DIP

switch

4-5

is

set

to

the OFF position this check will

not be performed. Since it

is

unlikely

that

the

data

will be corrupted, it

is

often

more convenient to set the switch to OFF.

It

is

necessary

to

perform a reset

in order

to

activate this

DIP

switch. Take care

not

to

alter the country settings.

When setting the size

of

the RAM disk using the CONFIG program,

if

the In-

telligent RAM Disk

is

connected, the size will be displayed but there will be

no

option to change the size.

The Intelligent RAM Disk unit has its own battery to preserve the contents

of

the memory when the PX-S

is

not

in use. This backup switch should be set

to

ON when the unit

is

installed. However,

if

the unit

is

disconnected from the

PX-S for long periods

of

time, the switch should be turned

off

so

that

the bat-

tery does not completely run down.

The battery does not allow the Intelligent RAM Disk unit

to

be disconnected

and then used on a different PX-S while still keeping the contents

of

memory

intact.

4-20

4.1.4 Floppy disk drives

Additional Floppy Disk Drives are provided for use with the PX-S.

As the drives are a separate item, they have a their own manual

to

show how to use them. There are also separate programs for copying and formatting disks plus other software. Use

of

these programs

is

covered in the manual supplied

with the disks.

Please consult your EPSON dealer for further details

of

the Floppy Disk Drives.

4-21

4.2 RS-232C interface

The PX-8

is

equipped with

an

RS-232C interface and the operating system sup-

ports a communication speed

of

up to 19200 bps. The RS-232C interface

is

used to communicate with other computers, to modems acoustic couplers and printers and other devices which support this communication standard.

The operation mode

of

the RS-232C interface can be specified with the CON-

FIG

program in Chapter 3 or by using the

OPEN

command in BASIC.

The SHIFT-IN/SHIFT-OUT and

XON/XOFF

functions are also supported

by the operating system, but can only be set by BASIC.

The

SHIFT-IN/SHIFT-OUT

protocol allows the full ASCII code from 0 to

255 decimal, but only using seven bits.

It

only operates during seven bit trans-

mission. When a code greater

than

127

is

required, the SHIFT-OUT (SO) code

is

sent to tell the receiving device to set the high bit, i.e. to add

128

to the code

received. Thus

if

the code

65

is

sent when the SO has been sent the receiving

computer will interpret it as code

193

(65

+ 128). The SHIFT-IN code reverses

an

SO condition.

If

a code

193

is

sent

at

when

an

SI code has been sent the

code will be interpreted as code 65. The SIISO codes act as a switch.

For

exam-

ple all characters will have the high bit set until the SI code

is

sent once

an

SO code has been sent. When communication occurs with two devices using

XON/XOFF

protocol, the

transmitting device can be told by the receiving device

to

wait until the receiv-

ing device

is

ready to handle further information. This

is

important

if

the receiv-

ing device

is

processing the information and needs time to carry

out

some

operations before receiving more data.

The codes for SIISO,

XON/XOFF

are:-

Decimal Hexadecimal

SO

14

0E

SI

15

0F

XON

17

11

XOFF

19

13

A warm

boot

will set the default setting

of

SIISO

and

XON/XOFF

to off, and

thus to ensure they are

not

active, perform a warm boot before using the CON-

FIG

program to set the parameters.

4-22

NOTE:

The CONFIG program does

not

allow the

XONIXOFF

or

SIISO

protocol to

be

set. This can only be done

from

BASIC,

or

a machine code

BIOS

call.

WARNING: When sending data which could contain these characters

for

example a

machine code program, the

SHIFT-INISHIFT-OUT

and

XONIXOFF

options should

be

set to

off

If

this is

not

done, when the receiving device

is sent any

of

the above characters it will

be

interpreted as such

and

the appropriate action will be taken. Consequently the data received will have the bit setting ch9nged in the case

of

SIISO.

Also

the particular character

being sent as control data

(SIISOIXONIXOFF)

will

not

form

part

of

the data received as it will have been interpreted as a control character.

Before using TERM

or

FLUNK execute a warm

boot

to set the RS-232

parameters

to

the default, and then change them using the CONFIG program

if

necessary. This ensures the SIISO and

XON/XOFF

parameters are set to off.

The RS-232C interface can also be used in BASIC programs. For details

of

use,

refer to the PX-8 BASIC Reference Manual.

The PX-8 uses the RS-232C interface

to

connect a printer unless the system

configuration

is

changed with the CONFIG command.

Examples

of

use

The following command transmits the contents

of

file SAMPLE. TXT to the

RS-232 interface.

PIP

PUN:

= A:SAMPLE.TXT

The following command receives

data

from the RS-232C interface and saves

it

on

the disk in drive A: under the file name SAMPLE2.DAT.

PIP A:SAMPLE2.DAT

= RDR:

The default settings

of

the RS-232C interface operation mode are as follows.

Communication speed: Character length: Number

of

stop bits:

4800 bps 8 bits

2

Parity check: SIISO control:

XON/XOFF

control:

4-23

No No No

NOTE:

A warm boot will always return the RS-232C settings to' ihese defaults.

The RS-232C interface connector

is

provided

on

the rear panel.

Fig. 4.13

The pin assignments and signal descriptions are as follows.

RS232C

SERIAL

3~:

4~8

6 7 E

_Fig.

4.14

4-24

The standard RS-232C interface

is

connected to external devices through a minia-

ture connector. Pin ;ssignments

of

this connector are as follows.

No.

Signal

Description

of

Signal

Symbol Direction

I

GND

-

Ground

2

TxD

OUT

Transmitted

data

3 RxD

IN

Receive

data

4

RTS

OUT

Request

to

send

5 CTS

IN

Clear

to

send

6 DSR IN

Data

set ready

7

DTR

OUT

Data

terminal ready

8

DCD

IN

Data

carrier detect

E

FG

-

Frame"

ground

NOTE:

The direction

of

signal is as viewed from the P X-8.

The meanings

of

the various signals are as follows.

GND (Ground) This terminal

is

used as the return line for the following signals.

TxD (Send data) TxD

is

the signal used from transmitting data from the PX-S to the device (acous-

tic coupler, etc.) with which the PX-S

is

connected. This

is

possible when the

Clear to send signal

is

on.

RxD (Receive data) RxD

is

the

data

signal from the acoustic coupler or other RS-232C compatible

device to the PX-S.

RTS (Request

to

send)

RTS

is

the signal which controls the communication function

of

the device

(acoustic coupler, etc.) connected

to

the PX-S. The connected device becomes

ready to send when this signal

is

ON.

CTS (Clear to send) CTS

is

the signal which indicates whether the connected device

is

ready to ac-

4-25

cept

data

transmissions. Transmission

is

enabled when this signal

is

ON and

disabled when it

is

OFF.

DSR (Data set ready)

DSR

is

the signal which indicates whether the connected device

is

ready for oper-

ation. When this signal

is

ON, the applicable device

is

connected to the inter-

face cable and

is

ready to accept data transmission/reception control signals.

DTR (Data terminal ready)

DTR

is

the signal output by the PX-8

to

the connected device

to

indicate that

it

is

ready to receive data.

DCD

(Data carrier detect)

The DCD terminal

is

used for detecting the carrier signal from the connected

device.

FG

(Frame ground)

This terminal

is

connected to the chassis

of

the PX-8; ordinarily, it

is

also con-

nected via the external cable to the corresponding terminal

on

the other device.

RS-232C cables

Please consult your Epson dealer for the correct type

of

cable to connect to

the other equipment. The cables available from EPSON are as

follows:-

1)

Cable # 724 This cable

is

used to connect the PX-8

to

a modem

or

acoustic coupler.

2)

Cable #

725

This cable

is

used to connect the PX-8

to

a computer which

is

equipped with

an RS-232C interface and a DB25 connector.

It

is

also used to connect the

PX-8 with a serial printer

or

other

110

device which

is

equipped with an

RS-232C interface.

3)

Cable #726 This cable

is

used to conllect two PX-8s through the RS-232C interfaces.

This

is

also referred to as the null modem cable.

4-26

PX-B side

mini

connector

TxO

2

RxO 3

RTS

4

CTS

5

OSR 6

OTR 7

OCO

B

0825

connector

2

3

4

5

6

B

9

19

20

21

25

Fig.

4.15

Cable #

724

4-27

mini

connector

0825

connector

CGE~

GNO

1

TxO 2

-~~,

2

RxO 3

3

RTS 4

4

CTS

5

OSR 6

6

OTR 7

OCO B

B

9

19

20

21

25

Fig.

4.16

Cable #

725