Unitron U-2200 Operation Manual

U

2200

U

2200

U-2200

U-2200

U-2200

CONTENTS

Digitalizzazione di

Tiziano Garuti

CHAPTER 1 INTRODUCTION

CHAPTER 2 INSTALLATION

CHAPTER 3 U·2200OPERATION

CHAPTER 4 VIDEO

CHAPTER 5 INPUT/OUTPUT

APPENDIX

..•••••..•...••...••.....

••••••••••.•.•.••.••••.•••...•

....•.......•..•..

...........•......

••••••......••.....

..........••....

PAGE 1

PAGE 6

PAGE 8

PAGE 17

PAGE 24

PAGE 33

www.1000bit.net

UNITRON 2200 PERSONAL COMPUTER

The U·2200isa

the

infonnationonthe

in

APPENDIX A lists several references which may aid you

la~ages

and operating systems.

CP/M~

compatible microcomputer. This manual covers

config.n8tion. installation and operation. The bibliography

in

useofvarious

CHAPTER 1

INTRODUCTION:

The U-2200 system has two major parts: Computer chassis and detached

keyboard. A coiled cable connects between

In

this manual

machine,infiG.

'·1.

all

descriptionsofdirection are basedonyour

them.

facing the

On the frontofthe chassis,asshown in

and

a keyboard connector.

FIG. 1-2

FIG.

,.,

Front

I

fiG.

1-2, there are a power indicator

P8ne4

The rear panel has several connectors (Fig. 1-3) for Disk Drives, Video

Monitor, Cassette Recorder and Joy stick.

required
with Apple

to

make a functional computer.Italso has 5 extention slots compatible

II

peripherals. These slots are numbered

#1,

#3,

#4, #5 and

#7.

GAME TAPE TAPE

I/O

OUT

The chassis contains

of

chassis. and you
board. The power supplyisa high frequency switching mode and proYides four
DC

Voltages: +5V, +12V,
ACor220V AC, switch selectable (FIG. 1-4). The
to

the

computerboard via a

Fig.ne 1-5.

will

see

IN

the

the

-5V,

G-pin

VIDEO DRIVE

computerboard and power supply. Open
power supply on

-12V.

The sourceofpower

connector. The

1

the

ri~t

outputofpower supply connects

connector

DRIVE

2

side above

the

canbeeither 110V

pinoutisshown

the

cover

computer·

.[][].

220V

110V

::[J]

FIG.

1-4

,...-------------------_.----------------------_ ~

1 GND +12V

, ,

~

COMPUTERBOARD:

The U·2200

includes the

ROM

6502

(Read only Memory). IC's (Integrated Circuits) and

-

-----

-- .---------------

FIG. 1-5 Power Pinout

is

a single board computer. The computerboard (Fig.

and Z·80 microprocessors,

-5V

2

-12V

RAM

+5V

--------

(Random Access Memory),

--

+5V:

-.

-_._~

other

1-6)

components

in

FIG,1-6

VIDEO DISPLAY:

Display type: Memory
Displaymode: Text, Low-resolution Graphics, High.Resolution Graphics.

Text capacity:
Character type: 5x7
Character_set: Upper/Lower case ASCII

Character modes: Nonnal, Inverse, Flashing
Graphics capacity: 1920 blocks (Low-Resolution)

In

the

marked "VIDEO". This connector allows

closed-<:ircuit video monitor. Itisa female

and a
rear conner, there
"?odulator that can connecttoeither

Video

soft-switch functions.Ifyou have an
you can plug
"SO-<:ol

input"

960

53760 dots (High·Resolution)

centerofrear sideofthe

isa4·pin.connector

the

outputofan

giving you automatic video switching.

mapped display

characters (24 lines, 40 columns)
dot

matrix

Computerboard

computerboard thereisa metal connector

you to attach a -rable between

(ie. auxiliary video connector) for an

TV

SO-<:olumn

ina40

in

setorvideo mointor. The U-2200 has

SO-<:olumn

video into a 2-pin Connector marked

by 4S array.

a 2S0 by 192 array.

RCA

phono

jack. On

card pluggedinslot #3,

the

U.2200

the

right

RF

3

THE

CASSETTE INTERFACE:

Keyboard

On the right of the rear edgeofcomputerboard are two small black packages

labeled "Tape in" and "Tape

These are miniature earphone jacks into which you can plug two cables,
one for recording and the other for play back, which has a pair of miniature
earphone plugsoneach end. The other end of this cable can be connectedtoa
standard cassette tape recorder so
audio cassette tape and read it back

THE

DISK DRIVE CONNECTORS:

The U-2200 computerboard includes the disk controller's functions which
made by the advanced technology of
connect two drives. The connectors are located at the rear leftofthe computer­board. This controller lin dedicated slot

If

you wishtouse more than two disk drives, plug extra disk interface cards

extention slots and connect drivesasyou need.

THE

GAME

purpose of the Game I/O connectoristo connect special input and outpUt devices
to

enhance the effect of programs, especiallyingame programs. This connector
allows youtoconnect three one-bit inputs, four one·bit outputs, a data strobe,
and four analog inputs,

KEYBOARD:

with a coiled cable

U·2200 will be through the keyboard.Inthe keyboard case thereisan 8 ohm
speaker controlled
location number 49200. Any referencetothis address lor the equivalent address

-16336orhexadecimal SC030HI

I/O CONNECTOR:

To

the right of cassette connectorsisa 16-pin socket for game I/O. The

The

U·22OO

has a detached keyboard which connectstothe computerboard

by

out".

that

your U-2200 can

again_

PAL@

#61

all

of which can be managed by your programs.

by

a 15·pin female connector. Most of your contact with

a soft-switch. This soft·switchisassociated with memory

will

cause the speakertoemit a click.

sequencer,soyou can directly

can drive two 5%" floppy disk drives.

save

information on

Number of Keys: 72

Coding: Upper/Lower case
Output: Seven bits plus strobe

Power requirements: +5V at 300

Special key: Numeric Keypad and

function keys

in

FIG.

VIDEO MONITOR

To operate the U-2200 system, you

TV

se~.

If youdonot have a monitor and yourTVset does not have a video input,

you

Will

need an

!V

channel frequency for display on a TV receiver. Remember, when a television

IS

u~d,

monitor.

the quality of the display will notbeas good as the display on a video

RF

modu!atortomodulates the video

MA

'-7

ASCII

Keyboard

will

also need a video monitor or a

output

signal on a standard

4

5

CHAPTER 2

INSTALLATION:

There are four connections you must make. They are power. video outPUt,

keYboard, and disk drive. They are normally made on

The power supply

110/220V

AC

selectable. check

is
and set the switch to suit. The power receptacle
Insert the end

Video

for

RF

the RCA connectororthe video

of

the

supplied power cord into this connector.

outputisprovidedateither

modulator.Ifa normal video

CM,ltputofan

the

RCA

monitorisbeing used, it can connect

set, connect ittotheRFoutputofanRFmodulator.

The keyboard has a coiled cable ended with a 15·pin O·type connector.

Plug this connector

the

On

drives. Connect

If

the 80<:01umn cardisused. plug it into slot #3, and

of

the

8O<:0lumn card connects to

to

the

male connector on

left rearofthe

your

master driveinthe connector labeled "drive 1".

computerboard are

the

the

2-pin connector on
The U·2200 provides an auto-switching function between
display.

If

can be

plugged into any

a printerisused, plug

empty

the

printer interface card into slot #1. Other cards

slots accordingtotheir instruction manuals.

GETTING STARTED

is

The U-2200

a dual processor computer system. Both the

microprocessors are supported for full, compatible operation

the

Turn

The screen

power' on after set-up. You will hear a

will

show

the

messageinFIG. 2-1.

the

computer

is

locatedinthe

connectororthe

RF

modulator.Ifyou

front panel.

two

20-pin connectors for disk

in

"beep"

rear panel.

your

upper right corner.

4-pin connector

the

the

riltltofslot #7.

80/40

character

6502

one computer.

from

power source

to

usea·TV

video

output

Text

and Z-80

the

speaker.

UNIT

RON

DUAL PROCESSORS COMPUTER SYSTEM

WITH

AUTO·BOOTING CP/M.

DISK

CONNECT
AND INSERT

PRESS ANY

DRIVEINDRIVE 1 CONNECTOR

CP/M

SYSTEM DISKETIE.

KEYTOSTART!

FIG. 2·'

If

therei,no responseorsomething strange happens, please turn the power

off and check

1:
2:

3:

4: Peripheral cards

the

following:

Keyboard connector and its direction.
Power connector and power source switch.
Video connector and 80<:01umn videoifinstalled.

in

slots.

5: Disk drive connections.

is

make sure every connection
does

not work, press "control-reset"

the correct message appears on

Once

diskette into drive 1 and press any key

If

a message appearsasFIG. 2-2, it means th'at

the

disk controller. You can press any keytotry again.

···CAN

NOT FIND DISK CONTROLLER.

PRESS ANY

correct, then turn the power on again.Ifit still

or

check

to

boot CP/M.

KEYTORETRY

FIG. 2-2

The U-2200 has one

It boots

the

system from diskette.

The U·2200 has 24K
switches. Referercing
to

bankO.You

can add a

the

address

ROM

ROMonthe

ROM

CARD for your applicatons.

computerboard.

space split into two banks, switched by soft-

$COAO

will

the

connections again.

the

screen, insert

the

the

computer can

This

ROMisa

switchtobank 1, address

CP/M

system

not

boater.

$COAF

find

6

7

CHAPTER 3

U-2200 OPERATION

The U-2200

microprocessors are supported for

All

circuitry except the power supply

TIMING

System timingisderived from

the computerboard.

SIGNAL

14M

7M

i>O

~1

03

The video cootrol and addressing signals are also generated by this circuitry. Video
generation consists
24

lines of eight scan lines each. Fifteen synchronization signals are used. They
consist of
V4
through
vertical screen line.

MEMORY

Memory (ROM), and I/O locations. The memory mapisshownasFig. 3·2. The
RAM

spaceis24K andissplit into 2 banks. Softswitches are usedtoselect the Bank

oor Bank 1

"H"

signals are used to define the vertical line position on the screen. The

Vc

Memory

memory range $DOOO·$FFFF can be accessed like a lan!J.lage carel.

ROM

is

a dual processor computer. Both the 6502 and Z-80

full, compatible operation

is

located on a single computerboard.

the

14.318 MHZ crystal locatedatAl

Table

3·'

TimingSignllb

DESCRIPTION

Master oscillator output. Usedtoderive

7.159MHz timing signal.

1.023

MHZ

phase 0 system clock. Complement

referred

1.023
General purpose timing signal. Twice the
clocks.

signals are usedtodefine the vertical scan line position within the

in

to

as;2inother literature.

MHZ

phase 1 system clock.

but

asvmmetrical.

of

192 scan linesonthe video screen. These are grouped into

(Horizontal) and

U-2200 consists of Random Access Memory (RAM), Read-only

area. (Table 3·21. Power-on initializationisin

"V"

(Vertical) groupsofsignals. Thevathrou!tl

other

in

one computer.

timing signals.

to

;1.

Sometimes

fre(JJency of the system

ROM

bank

O.

on

Va

~

'---

~

w

•

0

•

•

0

~

w

•

•

•

a

~

a

•

EO

I--

a

•

SO·COLUMN

VI

>

~

"

~

0

•

•

w

~

0

~

8O{40 COLUMN

VIDEO

KEYBOARD

•

0

•

a

•

a

"

a

•

a

•

~

w

z

a

a

;;

u

VIDEO

ADDRESSING
TIMING

tRAM

MUX

ADDRESSING

SIGNALS

VIDEO

DATA

H

LANGUAGE CARD

CONTROL

ROM

RAM64K

r-

I--

ZOO

6502

I--

ANALOG

12

-

w
w

•

"

•

•

U

~

u

~

>

0

w

"

a

"

PERIPHERAL

•

w

~

•

w

~

•

a

0

0

I/O

FIG.3·'

8

System Block Diagram

9

ADDRESS

$FFFF
$DFFF

$0000

$Cooo

..................•..................

$6000

..........••.....•••......•••••.................••..

~

$4

.....•••...••••...••......•••....................••.

$2000

.....•.....••.....•••......•.........

SOBFF
$0800
$0400

$0200

SOl00

$0000

LANGUAGE CARD AREA:

to enable and disable
whichever bank of
4K

In

...........•.......•.......•.•...................••

.....••......•••....•••.•....•••.....

......•.•....•.......•......••.......

......••......•......••......••.................•.••

..............•.....

The upper

block of

location F8. thereis28-pin socket for

RAMinthe

The system uses

ROM

BANKO

~~~

.....•.....

~?~ ~?~

, " .

FIG. 3-2 System Memory Map

Table

3·2

Soft

Switch Address for

Address

16KofRAM

ROM

ROMisselected. The architectureissuch

eig,t

appearsasa Language card. Soft switches are used

and

SD~-$DFFF

4164 dynamic RAM's locatedinpositions

ROM

BANK

'.'

~~~

1

RAM

~~O

~~

~~?~

I~~

HGR2

~~~~

.........••

~~~~~

~~~~'

_

••.•....••..

ROM

BANKO

SCOAF

RAMinthis address range and are effective for

memory range.

ROM

space. This

STACK

_ _.

SYSTEM

USE

Selection

BANK

$COAO

will

.......••.

.........••

1

that

there are two

E4-El'.

accept the 24-pin

.
.

_

.

booter

ROM.

aligmented at the bottom. which will

ROM

the

3-5. Table 3-6

Signals

ROM1
ROM2 SELECT

CE,

BANK O/BANK 1

AO·A12

00·07

CARDtouse the 24K

is

ROMl SELECT

BANKO!BANKl

SELECT

DE

ROM

space. The socket pinoutisshown in Fig

the description of the signals.

1

2

A7
A6
A5

A'

GNO 03

3

•

5

6

10

11

12
13

7
8

•

A3
A2

A'
AD
00

01
02

"

FIG. 3-5

Table

3-6

Description

ActiveLowhen the addressis$FOOO-$FFFF of
Active

banks.
Active
The Booter

Hi

Lo
Address Bus.

Data Bus.

Lo

when the addressisSDOOO-5EFFF

Lo

when the addressisSFOOO·SFFFFofbank

ROMisenabled by this two signals.

wheninBank

whenisBank 1.

O.

boot

CP/M.Itwill also accept

28

ROM2 SELECT

27

A'2

26

vee

25

A8

2.
A.

23

All

22

DE

21

AID

20

eE

I.

07

'8

06

17

05

16

D.

15

6502

The 6502isa dynamic microprocessor operating at 1.023

It

uses the address and data busses only when the

¢O

is

low, the microprocessorisdoing internal operations and does not need the

address and data busses.

tflJ

signalishigh or active. When

MHz

BANK

1.

of both

clock rate.

O.

10

11

Z-80

The l-BO microprocessorislocated on the computer board andisbuffered

to

the address and data busses. The Z·80isconfiguredtoallow direct execution

of 8080 and l-BO programs and operate under the

CP/M

operating system. The

computer supports a 56K CP/M confi!J.Iration.

The

Z·BO

address bus interfaceisconstructed such

that

exist between the
microprocessor and
to

the

Z·80 versus normal

ADDRESS

6502

CP/M

are resolved. Table 3·7 shows how memory appears

6502

BUS

INTERFACE

that

the memory conflicts

based system and conventions used by the Z·80

configJration.

TIMING

,The 2-80issvr:chronized and phase lockedtothe

the, video refresh

perrods

the third
low until the startofthe

and a small partof,1.

of

¢(J. The.

tow during the time

t~e

Video
for

CONTROL

normally contains a peripheral

ensure

prevent switching back

to

~at

In

The Z·80 remains
address infonnaton on the bus. At this
no further wait
area

of

135 nanoseconds. The first half·dockishigh the secondislow and

is

high. At

2.041 MHZ.

Each

type.

read/wr~te

Z·80 occur when the clockishigh, they must

update accessisoccurring. Thus, each ¢(J has stable addresses on

the

entire durationofthe

The Z-80.

that

the

When the U·2200 power

the

off state. The RESET signalissynchronizedtothe

a write operation

the

WAIT mode and remainsinthis mode until activated.

Upon receiptofa writetothe

of

memory, by the Z-80. will return

period,

of

is

contr~lIed

6502

in

cycles required. Receiptofanother writetothe

411,

the7MHZ

the

endofthe

next

This timing scheme creates an effective 2-80 clock rate

~achi~e

signalISsynchronized ensuring

the

2-80 clockishigh. Because

will

not

to

the

cannot

the wait mode until

third half clock

tP1.

cycle contains one memory access period during

cycle.

by write commands to

ROM.Itis

perform two accessesinsuccession which would

6502.

is

turned on,

be interrupted. The Z-80isimmediately placed

clockisdivided into three half clock

the

sig'nal

Thus, the Z·80 clockislow during

that

all

all

occur during¢lwhile

the

nec:essaytouse write commands

the

RESET signal forces

SC2oo-SC2FF area

one

memory dycle occurs with z-aO

point

the Z-80isallowed to run with

the

Z·80tothe

WAIT mode.

6502

clocks. During

goes low and

the write can only go

address transitions from

areaofmemory

•

system clock to ensure

the

Z-80isenabled

$C200.$C2FF

re~ains

all

of

tfAJ

the

the

bus

that

to

the

Z.80

3--7

Tlible

6502

2-80 address

$0000
$1000
$2000-$2FFF
$3000-$3FFF
$4000
$5000
$6000-$6FFF
$7000-$7FFF
$8000-$8FFF

$9000 ­$AOOO-$AFFF
$BOoo -

$COOO

$0000-$OFFF
$EOOO-SE
SFOOO

Note

that
without
area.

PERIPHERAL I/O

These connectors are used for peripheral interface boards designed for
or
with each
of

accessing the

the

Along

the

AppleIIComputer. Peripheral Board I/O space has been set aside for use

of

the

the boards installed.

-$OFFF

-$1FFF

-$4FFF

- S5FFF

$9FFF

$8

FFF

- $C FF F

FF F

-$FFFF

the Z-80 can address cootigJous memory from

6502's

rear sideofthe computerboard are five peripheral I/O connectors.

five slots and thereisalso a 2K common area for use by any

Zero pageofmemoryorthe

$1000-$1

$2000 - $2FFF

$3000-$3FFF
$4000 ­$5000 ­$6000-$6FFF
$7000-S7FFF
$8000
$9000-$9FFF
$AOoo ­$8000
$0000-$OFFF
$EOOO-$EFFF
$FOOO-$FFFF
$COOO

SOOOO

address

FFF

$4FFF
$5FFF

-$8FFF

$AFFF

-$8FFF

-$CFFF

- SOFFF

$OOOO·$DFFF

peripheral

I/O

the

memory

U-2200

12

13

Eachofthe slotsisnumbered. They are #1, #3, #4, #5 and

the

five

5O-pin
3·8 provides detail on the signals available
showninFIG. 3-6.

PIN

2-17

18

20

21

SIGNAL

I/O SELECT This signal

AO·A15

RIW

I/O STROBE Normally high,

ROY

22

23

24

25

26

INTOUT

DMA

+5V

GROUND

connectorsisindividually selected by control circuitry. Table

at

these connectors. The pinout

Table 3-8 peripheral I/O signal descriptions

DESCRIPTION

is

normally high. It becomes low during

q,o

when a referenceismaketoSCnXX, where

the slot number.

The buffered address bus. The address on these pins

OUT

becomes valid through

Buffered ReadflNrite signal. This signal become valid
the

same time the address bus does, and goes high during

a read cycle and tow during a write cycle.

address
$CFFF.

The
1/11
of

Pulling
and halts
resistor to +5V.

Daisy-<:hain interrupt
This pin

Daisy chain
This

+5V volt power supply. 3 Amps
at

System electrical ground.

bJs

contains an address between

6502's

halts

the

pinisusually connected to pin 27

the

RDY input. This signalisgoing low during

the

6502

current

peripheral slots.

location being fetched.

this line low disables the 6502's address bus

the

6502.

is

usually connected to pin28(lNT IN).

DMA

¢(J.

this line goes low during ¢(J when

with

the

address bus holding

The lineisheld high by a 1K ohm

outputtolower priority devices.

output

#7.

Each

'n'

the

$caoo

to lower priority devices.

(DMA

IN).

is

available for use

the

and

address

of

29

is

30

31

is

32

33

34

36

37

38

39

40

41 DEViCE

42-49

50

RES

-12V

-5V

7M

OJ

,11

USER 1

'"

~~

SELECT

DO·D7

+12V

Non.Maskable Interrupt. When this lineispulled low
the

U-2200 begins an. interrupt cycle.

Interrupt Request. When this line

U-2200 begins an interrupt cycleif6502's

(I) flag

is

not

disable
When this line

cycle.

is

This line
this line
$FFFFisdisabled on

-12

volt powtlr supply, 0.5 Ampsisavailable for

peripheral slots.

-5

volt power supply, 0.5 Ampsisavailable for

peripheral slots.
7

MHZ

Asymmetrical 2
Phase 1 clock.

When this lineispulled low,
decoding

Phase 0 clock.

This signal becomes active - low, on a connector when
the

address bus holds an address between

$cOnF, where

Buffered bidirectional data bus. The data on these lines
become valid
should be stable no less

of

q,o

+12 volot power supply,
peripheral slots.

a input signal from peripheral cards. When

is

pulled low the

clock.

is

inhibited.

on a read cycle.

set.

is

pUlled low

the

MHZ

clock.

'n'isthe

300

nsec into ¢(J on a write cycle, and

the

ROM

slots.

slot number plus $B.

_~an

'2:.5

is

pulled low the

interrupt

6502

begins a RESET

address range of

all

$COXX-C7XX address

100 nsec before the end

Ampsisavailable for

$0000-

SCOnO

all

all

and

all

27

28

DMAIN

INT

IN

Daisy-<:hain
Usually connected

Daisy-<:hain interrupt input from higher priority devices.
Usually

DMA

input

from hiltler priority devices.

to

pin 24.

connectedtopin 23 (INT OUT).

14

IS

CHAPTER 4

VIDEO

SCREEN FORMAT

Three

different

to

which

your

U-2200

kinds

is

connected

of

information

(without

can

be shown on the video display

8O-column card);

0

GNO

DEVICE

DMAIN

USER 1

SELECT

INTIN

N"'

'Ra

RES

INH

-1211

-sv

N.C.

..

1211

7"

OJ

0'

00
07

06

OS
O'

03
02
0'

DO

27

"
"

JO

"

"

~I§

"

" "

3S

I~

"

I~

3S

l~

J9

'0

I~

"

"

"

"

'S

.,

"

13

I~

I~

13

"I~

~

~l~

0

FIG. 3-6 Peripheral Connector

.5V

DMAOlJT

"

INTOUT

2J

"

0

ROY

"

20

110

"

N.C.

ArN

"

"

."

"

."

'"

."

"

"

OJ

'"

"0

A9

"

"

A9

9

"

'7

,

'6

,

AS

6

"

S AJ

A2

•

,

All

2

"

,

1/0 SELeCT

....

STROBe

Pinout

1

, I Text. U-2200 can display 24 linesofnumbers, special symbols, and
upper/lower
are formed
space on either side

2) Low-Resolution Graphics.

array

40

3) Hi!tl-Resolution Graphics. The

280

dots

SCREEN

The video display uses informationinthe system's

display, The value

particular fixed object on

blocks, or a line
areaofmemory containing 1024 locationsisused as
infonnation.
Resolution Graphics mode, a separate, larger area (8,192 locations)isneeded
becauseoftile greater amountofinfonnation whichisbeing displayed. These
areas

of

SCREEN PAGES

There are actually two areas from which each mode can draw its information.

The first area

the

"secondary page"or"page2"andisan areaofthe same size immediately

following

The secondary page

to

be able to display instantly, A program can use

animaion by drawing on one page while displaying the other and suddenly flipping
pages.

case letters with40of

inadot

blocks wide and48blocks hi!tl.

wide by 192 dots high.

MEMORY

Text

memory are usually called "pages",

the

first area.

matrix 7 dots high and 5 dots wide. Thereisa one-dot wide

of

the

character and a one-dot

of

a single memory location controls

the

of

seven dots.InText

and Low-Resolution Grahics share this memory area.InHi!tl

is

called

the

"primary page"or"page

is

these characters on each line. These characters

The"

screen. This object can be a character, two stacked

useful for storing pictures or

hig,

space above each line.

U·2200 can present 1,920 squaresinan

U-22DO

and Low-Resolution Graphics mode,

can

also display a

RAMtogenerate its

the

the

sourceofthe

1".

The second areaiscalled

text

the

two pages to perfonn

dot

matrix

appearance of a

screen

which you wallt

of

an

16

17

Text

and Low-Resolution Graphics share
secondary page, justasthey share the same range for
mixed

modes which were described above are also available on the secondary

page,

but

thereisno waytomix

VIDEO DISPLAY MEMORY RANGE

P

Screen

Textllo·Res

Hi·Res

SCREEN SWITCHED

The
are called "softswitches", They are switches because they have two positions
(for example: on
are controlled by
by referencing the special memory location for

read from
of

the

location which throws

There are eight special memory locations which control the setting of the
soft switches for the screen. They are set up
location

mode

"off".

Screen Soft Switches

Location:

Hex

SC050
$eaSl
$C052
SCOS3

$C054
SC055
$C056
$C057

...

Primary
Secondary

Primary
Secondary

devices which decide between the various modes, pages, and mixes

or

off,

the

softwareofthe computer. A program can

or

writtentothe

of

the

pair yoo turn its corresponding mode

The pairs are:

Decimal

49232
49233

49234
49235
49236

49237
49238
49239

-16304

-16303

-16302

-16301

-16300

-16299

-16298

-16297

the

twO

pagesonthe

Begins

8t:

Ends

H.x

$400
$800

$2000
$4000

textorgraphics) and they are called

location are irrelevant; itisthe referencetothe

the

0"

1024

2048

B192

switch.

Description

Display a GRAPHICS mode
Display TEXT mode

Display
Mix
Display
Display the
Display

Display HI-RES GRAPHICS mode

the

same memory range

the

primary page, Both

same screen.

at:

Hex

$7FF

SBFF

$3FF

16384

TEXT and a GRAPHICS mode

18

$5FF

that

in

pairs; when you reference one

all

TEXTorGRAPHICS

the

Primary page
Secondary page

lO·RES

Ooc

2047

3071

16383

24575

"soft"

"throw"

switch. The data which are

"on"

and its companion

GRAPHICS mode

tor

because they

a switch

address

the

0«_

,O'

",

'"

...

'"

",

,

'"

...

0

10$

11
12$C

''''

....

""

"

"

"

SSSI

"

"

Sl

$7S1

"AI

""

$S28

5SA8

S62S
S6AS

5728
51AS

"DO

""

ssse

SSDe

S6Se

"DO

$7S1

SlDO

-

..

..

....

$8

..

..

..

..

..

..

I"".,

..

,

"

""

'"

•

•

, , ,

,

•

, ,

, ,

,

u

,

,

G W

,

,

"

•

, ,

,

,

(

, ,

M (

·

"

0

-

1124

1152

128111
1408

IS36

166.

1792

192111

10"

1192

1328

1448

1576

171114
1832

196f

110.
1232
1361
1488
1616
1744

1872

,,..

ASCII SCREEN CHARACTERS

FI_ino

..

"

'"

""

,

, , , ,

..

, ,

,

#

•

•

•

•

•

•

,

,

•

,

0

·

<

..

-

..

>

,

I

FIG.

..

... ...

•

, ,

, ,

,

, ,

G

"

,

, ,

M

"

0

4-1

O'

•

, ,

u

W

,

,

•

,

(

(

·

-

Mapofthe

..

...

#

•

•

•

,

,

..

..

-

,

19

IConuoU

".

...

'"

'"

,

•

,

, , ,

•

, , ,

,

•

,

•

,

•

,

G

•

,

"

0

, ,

,

, ,

<

..

M

>

,

"

0 I

Text

..

No,m,1

,

..

.....

..

#

•

•

•

,

•

-

,~

...

,

, , ,

,

,

•

•

•

,

•

0

..

..

<

..

>

,

,~

...

•

,

,

u

,

W G

, ,

y

(

,

.

-

screen

'"

'"

=

"'"

• •

•

, ,

•

, , ,

,

,

,

u

, ,

W

x

,

y

"

, ,

,

(

, , ,

,

M

.

"

0

-

~_""

,

".

.~

."

•

,

..

•

,

•

•

,

(

•

m

"

,

,y'

..

l

..

,

,

•

,

"

•

•

•

•

,

(

I

1

-

The TEXT Mode

In

the Text mode, the U-2200 can display 24 lines of characters with up

to40characters on each line.

Each

character on the screen represents the contents
of one memory location from the memory rangeofthe page being displayed.
The character set includes the 26 upper-case letters, the 26 lower-case letters,
the 10 digits, and 33 special characters.

The area of memorywhichisused for the primary

text

page starts at location

number 1024 and extendstolocation number 2047.Inmachine language, the

primary pageisfrom hexadeciaml address $400toaddress

$7FF;

the secondary

pageisfrom $800to$BFF. Eachofthese pagesis1024 bytes long. Those of

you intrepid enoughtodo

the multiplication will realize

that

there are only 960

characters displayed on the screen. The remaining 64 bytesineach page which

are

not

in

displayed on

PROM

on interface peripheral boards.

Fi~re

4·1isa mapofthe U-2200 displayintext

the

screen are usedastemporary storagebyprograms stored

mode, with the memory

location addresses for each character position on the screen.

THE LOW-RESOLUTION GRAPHICS ILO·RES)

In

the Low-Resolution Graphics mode, the U·2200 presents the contents

MODE

of the same 1024 locationofmemoryasfor the Text mode, butina different
format.Inthis mode, each byte of memoryisdisplayed notasan
butastwo blocks, stacked one atop the other.

The

screen can show an array

ASCII

character,

of blocks 40 wide and48high, each block can be white or black.

Since each byteinthe page of memory for Low-Resolution Graphic represent
two blocks on the screen, stacked vertically, each byteisdivided into two equal
sections, called "nibbles", Each nibble can hold a value from zero to 15. The
value whichisin

block of that byte on the screen, and the value whichisin

the lower nibbleofthe

byte determines the color for the upper

the lower nibble

determines the color for the lower block on the screen. Value 0isblack, the others

are white.

Fi!J.lre

4-2isa map of the U-2200's displayinLow-Resolution Graphics

mode, with the memory location addresses for each block on

the

screen.

5480

.."

5580

""

5600
5680

5780

""

5428
54A8
5528
55A8
5628
5M8
5728
51A8
$450
$400
$550
55Dlt
5650
$6D0
$150
57D0

1024
11
1280
1408
1536
1664
1792

1921'

1064
1192
1320
1448

1576

1704
1832
1960
1104
1232

1361'

1488
1616
1744
1872

2000

52

20

FIG.4-2

Map

of Low-Resolution Graphics Mode

21

THE HIGH·RESOLUTION GRAPHICS (HI-RES)

MODE

SlIM

'191

Sleae

Ine

SliM

'44'

S11se

1516

snM

Ill(

Sl2M

un

su..

1961

SUM

'*'

S2t1l

un

SllA'

.J6t

12m

",u

511....

1616

un,

'144

121

...1un

UnI

.,.

12)

...

1 911'

S2t541

Inl

S2tDl

....

121541

'511

UIDI

1656

512541

1114

n1D1 '912

12)541

91441

SllDl

9161

If

_

IIU._

1_-

l)fll_

1_,1_

111~11_

1'1"

11'"

111

...

1101

The U·2200 has a second
Graphics. When
display 53,760 dots

can

display black and white dots.

your

in

U-2200isin

a matrix

typeofgraphic display, called High-Resolution

the

High Resolution Graphics mode, it can

280

dots wide and 192

dots

high. The screen

The High-Resolution Graphics mode takes its data from an 8,192-byte

area

of

memory, usually called a

buffers:

one

for

the

primary page and one for

buffers are independent

of

"picture

buffer". There are two separate picture

the

secondary page. Bothofthese

and separate from the memory areas used for

Text

and Low-Resolution Graphics. The primary page picture buffer for the High·

Resolution Graphic mode begins

up

to location number 16384; the secondary page picture buffer follows on the

heels of

the

firstatmemory location number 16384, extendingupto

at

memory location number 8192 and extends

location

number 24575.

Each

dot

on

the

screen represents one bit from the picture buffer. Seven

of

the

eight bitsineach byte are displayed on the screen. Forty bytes are displayed
on each line
the

lineisdisplayed on

then

the

After one

dots

are displayed on eachofthe 192 linesofthe

The

the

dots

4-3

shows

the

memory addressesofeach lineonthe screen.

BO-COLUMN

The U-2200 has an

switches. Referencing the addresses SC051 and $C059

Text

display if you have the

or

$C050 will returnto40

the

80-<:01umn

of

the screen. The least significant bit (first bit)ofthe first byte

the

left edgeofthe screen., followed by

third, etc. The

byte

then follows the first bitofthe next byte, andsoon. A totalof280

most

significant (eighth)

bitofeach byteisnot

screen.

dots

whose corresponding bits are

whose corresponding bits are

the

U-2200's display screeninHigh·Resolution Graphics mode with

"on"

(or

~al

to1)appear white;

"off"

(or equal toOJappear black. Fi!JJre

SOFTSWITCH

80-<:ol

video Auto-switching function worked by two soft.

will switch to

80-<:01

cardinits slot. Referencing

column display. Most

CP/M

card and automatically switchto80-<:01

display if the cardisfound.

the

software will search for

the

second bit,

displayed.

80

column

address $C058

in

FIG. 4-3 Mapofthe

High·Resolution Graphics Screen

22

23

CHAPTER 5 INPUT/OUTPUT

The

U-2200 has several built-in Input

of

these I/O features are found in the remainderofthis chapter.

Keyboard

Disk

I/O

Speaker
Cassette

Game

READING

character. These seven bits, along

key has been pressed,

location. When you

128
character
associated numeric codes. The location will hold this one value until you press
another key, or until your program tells the memory location to forget the
character it's holding.

the keyboard's
to
location. When you reference this other location, the value contained
location will drop

key. This action

read

read
you can still recover

($801tott1e

These Ire the special memory locations used by the keyboard:

location

H

..

seooo

SC010

I/O

I/O

THE

KEYBOARD

The keyboard sends seven

are

availabletomost programsasthe contentsofa memory

pressakeyonthe keyboard, the value in this location becomes

or

greater,

Once your program has accepted and understood a keypress,itshould tell

receive a new

or writetothe

from that location

KEYBOARD SPECIAL lOCATIONS

and

the particular value

which was pressed. Table

memOfY

valueinthe keyboard location.

Decimal
49152
49168

locationto"release" the character itisholding

one.

Your program candothis by referencing another memory

below

128. This value will stay

is

called "clearing the keyboard strobe". Your program can either

special memory location; the data which are written to or

are

"the

code

-16384

-16368

biu

with another

irrelevant. Once

for the key which was last pressed by adding

Description

Keyboard Data

Clear Keyboard Strobe

and

Output (110) capabilities. Details

of information which together

sjgnal

which indicates when a

it

assumesisthe

5-1

shows the ASCII characters

you

have cleared the keyboard strobe,

numeric

low

until you press another

code

and

in

form

for the

and

prepare

the first

one

their

128

Decimal:

0

,

2 $2
3

•

S

•

7
B

•

10

11

12
13

,.

'S

X.y

_.

0

11

2"
3#

.,

S%

50

7'

B,

.1

.

~

.<

-"

>

A

"

B
C

0

E
F

Table 5·1 The

Hell:

$0

$1

$3
$4

$5

SO

$7

$8
$9

'A

'B
'C

'0

$E

SF

Alone

'AO 'AO 'AO

'BO 'BO
'B'

'B2
'B3
'B'

,BS
'B. 'B.

'B7 'B7
'BB 'BB

'B. 'B.
'BA
,BB

'AC 'AC
'AD
'AE

'AF

'C,

'C2

'C3

'C,

,CS

'CO

'28

$80

00'

~h

••

~.

~,

~q

~k

bo'

..

h<

If

~

If

"

~

.;

Table 5-2 Keys and their associated

'Bl
'B2
'B3

'B'
'BS

,BA
'BB

'AD

,AE
'AF

sa'
'82
sa3

$8'
sas

SHIFT

'Al

'A2
'A3 'A3

,

'AS
'A.
'A7
'A8
'A.

'AA

'AB 'AB
'BC 'BC
'Bo 'Bo
'BE
'BF 'BF

CTRL

'86

ASCII

14'

'90

dI.

",2

""

.oJ

"'.

Mk

"'"

~b

Q"

wb

-

~

..

"

"

"'

Upper case Mode

80lh

'AO

'CO 'CO

'Cl
'C2
'C3
'C.
'CS

'CO

..

'A'
'A2

'A'
'AS

'A.
'A7

'AS

'AO

,AA

'BE

sa,
sa2
$83
sa.
$8S

$8B

Character

160

'AO

".

'.0

, ,

"

#

,

% S E U

• •

,

I

·

•

-

I

Koy Alone

RETURN

G SC7

H

,

J

X

L

M

N

0

P@

0

R

S

T

U

V

W

X

y

Z

~

~

ESC

-,

Set

,.2

'CO

0

~

A 0
2 B
3 C

•

B H

•

<

>

0 T

F V f
7 G W

,

,

J Z

X

L

M

"

N

,

0 - 0

ASCII

codes

$80 $80

,ea

$C9

'CA
'CB
'CC
'CD

,CE
,CF

'DO
'0'

'02
'03
'D.
'OS
'D.
'07
'DB
'D.

,DA

$8B
,.S

'.B

'DE

208

'DO

p

A b

S

X h

y

I

I

J

-

CTRL

$87

$8B

...

saA
$8B
$8C
saD
saE
saF

$90

$91

'92

'.3

,

..

$OS

'96

$97

'98

'99

$9A
saB
,.S
,.B
S.E

22.

$EO

•

,

•

•

,

;

I

k

,

m

"

SHIFT

$SO

SC7

,ea

'CO

,CA

'CB
'CC
'CD

,CE
'CF

'DO
'0'

'02
'03
'D.
'OS
'D.
'07
'08
'D.

,oA

sa8
'.S

$9B

'DO

2.0
'FO

p

•

,

•

,

"

•

w

•

Y

,

I

I

)

Nb

80th

$80
$87

$8B

$8.
$8A
$8B
$8C
$80

$8E
'8F

$90

'"

$92
$93
$9'

$9S

'96

'.7
,.B

,.,

$9A

$8B

,.S
'.B

'.0

24

25

lower

case Mode

Alone

A

a

C

o

E

F

G

H

K

L

El

E2
E3

E.

E5
E6

E7

Ea

I

E9

J

EA

Ea

EC

Shift

C,

C2

C3 0

C4

C5 Q
C6

C7 S

ca

C9

CA

ca w
cc

Alone

M

ED

N

EE

EF

P

FO

F,

R

T

U

V

X

y

Z

F2

F3

F'

F5
F6
F7

Fa

F9

FA

Shift

CD

CE

CF

00

01

02

03

D'

05

06

07

08

DO

OA

The RESET key at the upper

generate

When

the keyisreleased, the computer starts a reset cycle.

alter the codes produced by

when the power

case characters.

DISK

will
connector which

an

ASCII code, but instead

the RESET

The CTRL

The power

I/O

The U·2200

boot

CP/M

and

CTRL keys

and

SHIFT keys generate no codes by themselves, but only

other keys.

li!tlt at the lower left-hand cornerisan

is

on. This keyisalso a switchtoset a flip-flop for upper!lower

has

two

disk

from the drive 1 connector. Table 5-3 lists the pin out of the

is

compatible with Apple disk drives.

right

corner of the main section does not

is

directly connectedtothe microprocessor.

are

pressed together,

I/O

connectors on the

all

prlXessing stops.

indicator lamptoshow

rear

panel. The booter

When

The U·2233 Keyboard has many predefined
keys and each key has autorepeat function. The operation willbefoundinKey·
board

operation sheet.

and

user-defined function

pin

'.3,5,7

2

•

6

8

o

10

1"

12

13,15,17,19

,.

16

18

20

Table 5-3

description

GROUND

QO

Q1

Q2
OJ

-12V

WR

REO

+5V

+12V

ENABLE

READ
WRITE
WRITE

DATA

DATA
PROTECTION

26

27

SPEAKER

I~side

the keyboard case, thereisa small 8 ohm speaker. Itisconnected

to

t~e

Internal electronics of the U·2200sothat

a vanety

~ft

tIme a program references

the
the
of

steady

4~200.

clICk.

CASSETTE I/O

for cassette I/O. The connector marked
the
soft ,switch for the cassette

location .

Referencing

zero to 25 millivolts,
of

wtllC~

repetl.tlon

duration
later use.

output

on
output

cassette tape recording.
tones on

pro~rams

again.

of

sounds.

T~e

speakeriscontrolled by a soft switch. This soft switchisnot

switches controlling

speak~r

stateISchanged;

the

U.2?OO

~e

Be

the

The other connector, marked "TAPE IN", can be used

will

change state: change form

speaker switch frequently and continuously, a program can generate a

tone

from the speaker.

The soft switch for

Any referencetothis address (SC030J

There are two small black packages labelled "TAPE

board, Thisisanother toggle switch, like the speaker switch. The

num~r

491.84 (or the equivalent

~I~

location will make

~ableis~IUgged

.'s recording

the

of

this tone, information may be encoded data on a tape and saved for

forewarned that if you attempt to flip

by

w~iting

recording. You should only use
soft switch.

the
or

data which were stored on cassette tape may be read back and used

onto

program produces a

to

tape, decoding them Into data, and storing theminmemory Thus

the

video modes,

the

memory address associated with the speaker switch

the

speaker produces a tiny "click".Byreferencing the address

the

speakerisassociated with memory location number

output

or

return from 25 millivolts backtozero.Ifthe

into

the

a tape, this wilt produce a tiny "click"onthe

its special location you

I.ts

main p:urposeisto provide a meansoflistening to

plug

the

MICROPHONE inputofthe

tone

"read"

butisinstead a toggle switch. Each

"in"to"out"orvice·versa. Each

will

"out"iswiredtoanother soft switch on

canbetoggled by referencing memory

-16352

voltage on the

on

the

will

operations when toggling

a program can cause it to make

like

cause the speakertoemit a

IN"

and "TAPE

or

hexadecimal SC0201.

out

connector swing from

cassette tape recoder

tape.Byvarying

the

soft switch for

actually generate two "clicks"

the

to

"listen"toa

other

tape.

pitch and

the

cassette

the

cassette

OUT"

the

tim~

end

By

The input circuit takes a 1 volt (peak-to-peakJ signal from
recorder's EARPHONE jack and converts it into a string
time the signal

or

vice,versa,
sending zeroes, and vice versa. A program can inspect the state
input circuit by lookingatmemory location number 29248orthe equivalents

-16288
is
location

can read the state of

is

usually much

GAME

input and
ly
four one-bit outputs, a data strobe, and four analog inputs to
of
to

controllers are connected

buttons are connected to two of the one-bit inputs.

ANNUNCIATOR OUTPUTS

can be usedasan input to some
can be connected to circuits

switch for
annunciator.
its corresponding annunciator
pair, you
the voltage
annunciator
determine
are:

or

greater thanorequalto128, then

is

I/O

The purpose

game progrin1s. The connector allows you

which can be controlled by your progr<ms. The Game controllers connected
cables can plug into

The four one-bit

Each annunciator

is

appliedtothe

the

input circuit changes state: ifitwas sending ones, it will start

hexadecimal SC060.1fthe value whichisread from this location

less than 128,

too

output

the

devicestoheighten

the

annunciators are arranged into four pairs,

If

you reference the first addressina pair, you turn the

rurn

the

on

its pin

is

"on",

current

then

the

cassette input circuit,

slowtobe abletomake any sense

of

the

Game I/O connectoristo allow you to connect special

the

to

outputs

is

controlled by a soft switch. The addresses of

annunciator's

on

the

voltageisnear 5 volts. Thereisno inherent means to

settingofan annunciator bit. The annunciator soft switches

input circlJit swings from positive to negative,

the

stateisa

the

stateisa

the

Game I/O connector. The two rotary dials on the

two analog inputs on the connector. The

are called "annunciators". Each annunciator

other

electronic device,orthe annunciator outputs

to

drive l<mps, relays. speakers. etc.

"off",

if you reference the ~ond addressinthe

output

the G<me I/O connectorisnear 0 volts; when an

"one",ifthe

"zero".

effectofprogramsingeneral, specifical-

to

"on",

of

ones and zeroes. Each

valueinthe memory

Although BASIC progr<ms

the

speedofa BASIC program

outofwhat

connect three one-bit inputs,

When an annunciatoris"off",

of

it reads.

the

one

pair for each

the

cassette

the cassette

U·2200,

two

push

output

the

soft

output

all

of

28

29

TABLE 5-4 ANNUNCIATOR SPECIAL lOCATION

STROBE OUTPUT

Ann

a

off
on

off

2

on

3

off
on

ONE-BIT INPUTS

The three one-bit inputs can each be connectedtoeither another electronic
device ortoa pushbutton. You can read the stateofany of the one-bit input
from a machine language or
the Cassette Input Addresses 49249 through 49251 (16287 through
or hexadeciaml $C061 through $C063).

ANALOG INPUTS

The four analog inputs can be connectedto150K ohm variable resistors

or potentiometers. The variable resistance between each input and the +5 Volt
supplyisusedina one-shot timing circuit.Asthe resistance onaninput varies,
the timing characteristics of its corresponding timing circuit change accordingly.
Machine
a numerical value correspondingtothe position of the potentiometer.

Before a program can start to read the settingofa potentiometer,itmust

first reset the timing circuits.
$C070l does just this.
in

the four locations 49252 through 49255 become greater than 128 (their
bits are set). Within 3.060 milliseconds, the values containedinthese four locations
should drop below 128. The exact time it takes for each location to dropinvalue
is

directly proportional to the setting of the game paddle associated with
location.Ifthe potentiometers connected to the analog inputs have a greater
resistance than 150K ohms, or there are no potentiometers connected, then the

valuesinthe game controller locations might never droptozero.

off
on

lan!1Jage

State

49240

49241

49242
49243

49244
49245

49246
49247

Address

Decimal

-16296

-16295

-16294

-16293

-16292

-16291

-16290

-16289

programs can sense the changesintiming loops and obtain

When

you reset the timing circuits, the values contained

$Ca58

$C059

$C05A
$C05B

$C05C
$C05D

$C05E
$C05F

BASIC

location

Hox

programinthe same mannerasyou read

number 49264

(-16272

or hexadeciaml

-16285

high

that

Thereisan additional output, called C040STROBE. whichisnormally

+5

Volts but

the control of a machine

by

referringtolocation number 49216

perform a

TABLE

Function

speaker

cassette
cassette

Annunciators

Flag.inputs

Analog
inputs

Analog
Clear

Utility
Strobe

will

drop to zero volts for a durationofone-half microsecond under

"write"

lan!1Jage

operationtothis location, you

or BASIC program. You can trigger this

(-1632

or $C04F).Beaware th.atIfyou

will

trigger the strobe

5-5: INPUT/OUTPUT SPECIAL LOCATIONS

out

In

Address

49200

49184
49256

49240
throug, through through
49247

49249
49250
49251

49252
49253
49254
49255

49264

49216

Decimal

-16336

-16352

-16288

-16296

-16289

-16287

-16286

-16285

-16284

-16283

-16282

-16281

-16272

-16320

Hox

$C030

$C020
$C060

$C058

$caSF

$C061
$C062

$C063

$C064

$C065
$C066
$C067

$C070

Read/Write

R

R

R

RNI

R
R

R

R

RNI

R$C040

"s~rObe"

tWice.

30

31

THE GAME

I/O

CONNECTOR

C040

STROBE

FIG. 5·1 Game

+5V

PBO
PBl
PB2

GCO
GC2

Gnd

1
2

3

•

5

6
7

8 9

1/0

16

'5

13

"

12

11

'A

Connector

NC

ANa
AN'

AN2
AN3

GC3

GC'

NC

Pinouts

APPENDIX A

REFERENCE

1. AppleIIReference Manual
(product number A2LOO01A)

2.

Basic Programming Reference Manual
(product

3. Apple1\Basic Programming Manual
(product

4.

The

(product

number

number

DOS Manual

number

A2LOOO6)

A2LOO5Xl

A2l0036)

Pin:

,

2-4

5

6,7.10,1'

8

12·15

Tibia

Name:

+5V

PBO·PB2

C040

STROBE

GCQ·GC3

Gnd

ANO-AN3

506

Gwn8 I/O Signal Descriptions

Description:

+5

volt

pOW'er

on

this pin mustbeless

Single-bit (Pushbutton) inputs. These are

standard

A general-purpose strobe. This line, nor·

mally hi1tl. goes low during

write cycle

through $C04F. Thisisa standard 74LS
TTL

Game

each be connected throu!1l a

variable resistorto+5\1.

System electrical ground.

Annunciator outPuts. These are standard

74LS

bufferedifusedtodrive

inputs.

74LS

outPut.

controller

serie'S

supply. Total

series TTL inputs.

to

any address from $C040

inputs.

TTL

outPuts

than

tjJJofa read

These

other

current

l00mA.

lOOK

and

than

should

must

drain

or

Ohm

be

TTL

5. Apple Pascal Operating System Manual
{product

6.

6502

7.

Programming

8.

Softcard Manual

The

9.

•

Apple n

•

CP/Misa trade markofDigital Research, lne.

•

Z·BOisa trade markofZilog, Inc.

number

Assembly lan!J.lage Progr<mmingbylance

CP/M Handbook

is

A2l00281

The

Z·BObyRodnay Zaks

with

MP/MbyRodnay Zaks

a trade markofApple, Inc.

A. levonthal

9,16

NC

No

32

internal

connection.

33