Commodore CBM 2001-16N, CBM 2001-16, CBM 2001-32, CBM 2001-32N User Manual

BUSINESS

COMPUTER

BUSINESS

CBM

MODEL

2001-16,

USER

16N,

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32,

32N,

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MANUAL

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only

and

©

Commodore

2001-16,

16N.32,

COMPUTER

USER

FEBRUARY

is

"All

MANUAL

1979

reviewed

subject

first

Business Machines,

rights

andisbelievedtobe

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materialinthis

to

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reliable.

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information

Commodore

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Santa

Business

3330

Scott

Clara,

Blvd.

Ca.

95051

Machines

TABLE

OF

CONTENTS

Chapter1.Welcometo

Chapter2.

UnpackingyourPETandturningiton

Chapter3.Basic

PET

keyboard

Screen

Chapter4.Beginning

The

PRINT

Variables

Direct

Literals

Functions

your

PET

keyboard

editor

input

BASIC

statement

and

program

statements

computer

Chapter5.Eiementaryprogramming

Unconditional

Data

Chapter6.

Advancedprogrammingtechniques

String

Subroutines

FOR

Subscrpted

entry

variables

conditional

and

functions

loops

variables

looping

1

3

n

19

32

38

Chapter7.PET

communication

PET

interfaces

Commands

peripheral

IEEE-488bus

and

devices

withtheoutsideworld

and

lines

operations

for

Chapter8.Machinelanguageprogramming

Allocation

Commands

Machine

Chapter9.Errorsanddiagnostics

Debug

BASIC

OS

error

of

memory

from

BASIC

language

techniques

error

messages

monitor

57

91

113

LIST

OF

FIGURES

2.1

2.2

2.3

2.4

2.5

2.6

3.1

6.1

6.2

7.1

Rear

viewofPET

PET

memory

Memory

ASCII

codeinmain

ASCII6bit

PET

graphic

PET

keyboard

Functions

Principal

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bus

mapbyfunctional

code

character

scan

expressedintermsofbuilt-in

pointers

viewofPET

2001

memory

codes

lines

into

PET

blocks

RAM

BASIC

functions

3

4

6

7

8

12

43

55

57

7.2

7.3

7.4

7.5

7.6

7.7

7.8

7.9

7.10

7.11

Edge

connectorsJ1and

PET

IEEE

connector

Receptacles

IEEE

standard

Parallel

6522

VIA

Parallel

ConnectorJ3contact

Second

PET

second

for

user

port

addressesinPET

user

port

cassette

pinout

the

IEEE

connectors

information

example

identification

interface

edge

J2

interface

port

connector

J3

57

58

59

61

62

63

7.12

Edge

connector

J4

63

iii

LISTOFFIGURES(continued)

7.13

7.14

7.15

7.16

7.17

7.18

7.19

7.20

7.21

7.22

Memory

Multiple

OPEN

Status

Default

Examplesofdefault

IEEE

Transfer

Byte

expansion

file

structure

for

write

from

for

readtoPET

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errors

parameters

bus

contact

bus

transfer

identification

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from

talker to

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parameters

sequence

listener

'

63

69

73

74

80

82

83

84

85

7.23

7.24

7.25

7.26

8.1

8.2

Signals

Status

IEEE-488

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Example

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for

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for

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Point

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operation

87

88

89

94

100

IV

LIST

OF

APPENDICES

A.

B.

C.

D.

E.

F.

Detailed

BASIC

Expressions

Space

Suggested

PET

memory

statements

commands—intrinsic

and

speed

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functions

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hints

1-

WELCOME

TO

YOUR

PET

COMPUTER

Congratulations

the

PET

2001

is

now

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short

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potentials

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WritetousatCommodore

withanewsletter

Commodore

3330

Santa

USA

360

Euston

London

England

3370

Agincourt

Ontario, Canada

and

welcome

you

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Scott

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10

Chapter

3.

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INT).

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II

31

LJ

Chapter

S.

ELEMENTARY

PROGRAMMING

Useofdecision

A

major

maybedoneintwo

advanceinBASIC

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written

IF-THEN

withaspace

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ways-unconditionally

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three

forms:

programs.

line

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Conditions

provides

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familiar

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screen,wecould

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six

relational

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with

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concept

order.

write

10

20

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operators:

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number)

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20,

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them

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preventaninexperienced

ASCII

characters

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allows

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terminatortoindicateacarriage

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a

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39

ASC

turnsacharacter

parameterisa

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65

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of

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string.

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49

The

ASCII

SEGMENTOFSTRINGS

In

many

casesitis

problem

middle

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ordertobe

whereinresponsetoan

intitial,

the

listbeorderedbylast

functions.

analyze

piecesofa

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convenience.

string.

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code

for

and

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are

essentially

intoanASCII

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desirabletoaccess

last

name.Itis

programming

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code

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important

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function

will

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for

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functions

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not

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oneofthese

three

and

define

mainly

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first

character

list.

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first

name,

provides

three

functions

all

three

for

programming

the

but

to

at

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specified.IfI

is

VARIABLE,I)gives

than

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expression

lengthofthe

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the

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the

returned.

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the

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function

negative,

and

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or

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the

255,anILLEGAL

are

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expressions

gives

"J"

string,

QUANTITY

characters

second

lengthofthe

greater

characters,

string.

from

expressionisMID$(STRING

string.

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"I"isgreater

than

255,

variables

right

numberofcharacters,

MID$

variable,

than

255,

thenanILLEGAL

rightmost

QUANTITY

characters

then

this

ERRORisprinted.

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than

and

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for

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from

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will

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lengthofthe

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expression.

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general

starting

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greater

are

returned.

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function

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with

the

"I"or"J"

than

the

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position

thenanull

which

numberofcharacters

leftmost

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than

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negative,orgreater

numberofcharacters

sameasspecifying

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than

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than

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all

of

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find

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last

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function.

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LEN

STRING

function

from

our

until

the

givesanexact

example,wecan

first

blankisencountered.Toimplement

countofthe

numberofcharacters

analyze

40

characters

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programweneed

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from

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rightmost

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the

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stringisstored

can

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writeageneral

10

INPUT"NAME:FIRST,

20l=LEN(A$)

30

IFM/D$(A$,I,1)

40I=I-

50IFl>0

60

1

PRINT

variantsofMID$

and

GOTO

"LAST

the

="'THEN

30

NAME=";MIID$(A$,

are

usingalengthof1tosearch

MID$.

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are

storedinthe

each

new

stringisadded,achain

string

pointstowhere

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and

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the

string

deal

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functions

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out

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programtoextract

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case

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positionofthe

string

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writearoutine

routine

areapointertothe

LEN

function

the

last

extracts

name

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location

this

byte.

name.

wherealengthisspecifiedasthe

blank

delimiting

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last

name.

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from

program and

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440

prints

usertoreshuffle.

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approximate

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functionsintermsofother

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functionisdefinedina

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FUNCTIONS

pointwehave

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functionsinthat

certain

expression

100

INPUT

110

INPUT

120

DEFFNA(V)=V/B+C

letter

the

following

FNX

FNJ7

FNKO

FNR2

functionsinlineitbecomes

might

B

C

functionis''FN"

followedbya

are

the

our

programasitispulled.

covered

become

functions.

DEF

valid

into

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all

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functions

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function

names:

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intrinsictoBASIC.

especially

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random

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index

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function.

notbedealt

preventsanILLEGAL

450

tests

for

the

endofthe

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trigonometric.

tedious

and

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facility

variable

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fromadocumentation

name.

is in

the

range1to

again.

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familiar

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could

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the

LEN(C$)

-1.

second

ERROR..

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460

allows

mathematics

write

code

standpoint

the

are

to

BASICtodefine

a

The

most

severe

one

line

(80-characters).

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variableinparentheses

definedtobe

are

consideredtobe

are

usedinthe

After

the

funtion

example:

130Z=FNA(3)

140?Z

When

the

DEFFN

characterofthe

with

the

name

where

be

spaceisconsumedbyrecursion.

Figure

the

dummy

definedintermsofother

6.1

limitationofuser-defined

any

expression

global

evaluation.

definition

statementisexecuted,asimple

name

are

two

variableisstored.

shows

some

String

has

functions

following

butitmay

(have

the

has

been

bit7,the

most

same

executed, a

pointers:anaddressofthe

The

DEF

FN.Anoutofmemory

user-defined

functions

functionsisthat

cannotbedefined.

the

variable

have

valueasin

nameiscalledadummy

only

one

user

variable

significant

bit,

text

they

mustbecontainedintheir

variable.Afunction

argument.

the

restofthe

defined

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variables

program),

function

canbeusedasin

entryismadeinthe

usedinthe

and

their

variable

settoindicateitisafunction

where

the

functionisstored

andanaddress

current

the

table.

name.

entirely

may

expression

following

The

Associated

codetoexecuteafunctionisre-entrantsothatafunction

error

will

which

are

occurintimeasthe

readytobe

usedinPET

available

BASIC

programs.

on

be

values

first

of

may

stack

42

FUNCTIONS

EXPRESSEDINTERMSOFBUILT-IN

BASIC

FUNCTIONS

SECANT,

SEC(X)

DEFFNA(X)=1/COS(X)

FORX<

COSECANT,

>n/2

CSC(X)

DEFFNB(X)=1/SIN(X)

FOR

X< >0

CONTANGENT,

DEF

FNC(X)=COS(X)/SIN(X)

FORX<>0

INVERSE

SINE,

COT(X)

ARCSIN(X)

DEFFND(X)=ATN(X/SQR(-X*X+1))

FOR

ABS(X)<1

INVERSE

INVERSE SECANT,

COSINE,

DEF

FNE(X)=-

FOR

ABS(X)<1

DEFFNF(X) =

FOR

ABS(X)>1

ARCCOS(X)

ATN

(X/SQR(-X*X

ARCSEC(X)

ATN(SQR(X*X-1)) +

+1))+nil

(SGN(X)-1)*rr/2

i

[J

INVERSE

HYPERBOLIC

COSECANT,

DEF

FNG(X)=ATN

FOR

ABS(X)>1

COTANGENT,

DEF

FNH(X)=-

FOR

ANY

SINE,

DEF

FNI(X)=(EXP(X)-EXP(-X))/2

FOR

ANY

COSINE,

DEFFNJ(X)=(EXP(X)+EXP(-X))/2

FOR

ANY

TANGENT,

DEF

FNR(X)=-

FOR

ANY

SECANT,

DEF

FNL(X)=2/(EXP(X)+EXP(-X))

FOR

ANY

ARCCSC(X)

(1/SQR(X*X-1))+(SGN(X)-1)*n/2

ARCCOT(X)

ATN(X)+it/2

X

SINH(X)

X

COSH(X)

X

TANH(X)

EXP(-X)/(EXP(X)

X

SECH(X)

X

+

EXP(-X))*2+1

■

, ,

U

u

.I

43

HYPERBOLIC

DEF

COSECANT,

FNM(X)=2/EXP(X)-EXP(-X))

FOR

X < >

COSH(X)

0

n

HYPERBOLIC

DEF

INVERSE

DEF

INVERSE

DEF

INVERSE

DEF

INVERSE

DEF

INVERSE

DEF

COTANGENT,

FNN(X)=EXP(—X)/(EXP(X)+EXP(—X))*2+1

FOR

X <>0

HYPERBOLIC

FNO(X)

FOR

ANY

HYPERBOLIC

FNP(X)

FORX> =

HYPERBOLIC

FNQ(X)=LOG((1+X)/(1-X))/2

FOR

ABS(X)<1

HYPERBOLIC

FNR(X)=LOG((SQR(-X*X+1)+1)/X)

FOR0<X<

HYPERBOLIC

FNS(X)=LOG((SGN(X)*SQR(X*X

FOR

X < >

COTH(X)

SINE,

ARCSINH(X)

= LOG(X+SQR(X*X+1))

X

COSINE,

= LOG(X+SQR(X*X

1

TANGENT,

SECANT,

=1

COSECANT,

0

ARCCOSH(X)

-1))

ARCTANH(X)

ARCSECH(X)

ARCCOSH(X)

+1)+

1)/X)

H

INVERSE

GOSUB-RETURN

We

have seen

intrinsic

expression

Often

several

one

place

The

linesofcode

that

GOSUB

automatically

A

subroutineisstoredasa

The

last

executing

howtouse

function.

anditmust

and

The

linesofcode

executedbya

are

remembersatwhich

to

the

following

lineofthe

the

subroutine

mainline

HYPERBOLIC

FNT(X)=LOG((X

DEF

FNT(X)=LOG((X+1)/(X

FOR

ABS(X)>1

the

DEFFNto

major

limitationofDEFFNis

fitonone

willberepeated

line.

GOSUB

command:

calledasubroutine.

line

numberitwas

line

after

COTANGENT,

■

createasingle

throughaprogram.

GOSUB

executing

seriesoflinesinBASIC

code

mustbea

after

the

RETURN

GOSUB.

ARCCOTH(X)

-1))/2

variable

thatitcan

5000

meansgoto

executing

the

subroutine

function

consistofonlyasingle

These

the

before

startingatthe

statement.

This

which

program

subroutine.

the

GOSUB

canbeused

lines

It

differs

code.

line

number

tells

specifiedbythe

BASIC

you

like

any

algebraic

canbecollected

from

GOTO

and

can

return

in

GOSUB.

wanttoresume

44

Example;

10

REM

20

GOSUB

30

STOP

50

REM

60

RETURN

THIS

IS

THE

50

THISISA

MAINLINE

SUBROUTINE

CODE

LJ

U

I

]

LJ

Ifwecould

Five

bytes

the

line

currently

number

GOSUB

The

physical

little

stack

Exampleofsubroutines

Consider

n!=1x2x

You

cannot

simple

10

100

110

120

130

140

The

routineonlines

example,

takeasnapshotofexecution,wewould

are

pushed

number

executing

and

text

entry

are

limitation

space

the

factorial

3x...xn

define

routinetofindn!for

INPUT

I=1:NF=1

NF=NF*I

1=1+1

IFI< =NGOTO

PRINT

suppose

onto

and

text

addressofthe

line

number

address

also

left.

this

you

from

eliminated.

on

the

function:

function

N

NF

100-140

wantabinomial

the

any

couldbeused

see

the

lines

10-20-50-60-30

stack

whenaGOSUBisexecuted:

GOSUB.

and

the

GOTO

the

stacktoresume

The

line

number

routine

handles

mainline

a

following

the

execution.

numberofGOSUB'sineffectatone

with

the

DEFFNcommand.Onthe

given

110

n (upto34).

many

times

coefficient:

(NF

denotesnfactorial)

duringaprogram

executedinthis

GOSUB

branch.

timeis23.

other

token,

the

AllFORentriesinfrontofthe

hand,

using

and

GOSUBisstuffed

RETURN

After

this

you

different

order

two

bytes

restores

many

thereisvery

can use

the

values

each

for

into

the

line

following

forN.For

,

LJ

J

(7)

The

program

10

15

20

30

40

50

60

70

100

110

120

130

140

m!

r!(m-r)!

would

be

PRINT"M=";

PRINT"R=";

N=M:GOSUB100:X=NF

N=R:GOSUB100:Y=NF

N=M-R:GOSUB100:Z=NF

BC=X

PRINT

END

I=1:NF=1

NF=NF*I

1=1+1

IFI<=N

RETURN

BC

/ (

INPUT

Y*Z

GOTO

M

R

)

110

LJ

u

LI

45

TYPE

RUN

for

the

valuesM=

RESULTIS462

R=6.

Subroutines

usedtoinput

results.

outputasshown:

WhenwemakeNequaltoM,R,and

Of

course,

function

NESTED

The

subroutineonpage

the

binomial

The

subroutine,

act

likea"black

the

data

and

For

example,inthe

N

some

subroutinesdonot

suchasprintingaspecial

SUBROUTINES

coefficient.

denoted

box"orcomplex

other

fixed

subroutineonlines

SUB100

NF=N!

SUB

6-14

itself

couldbeusedasa

Merely

SUB

change

10,

beginningonline10and

function

variables

NF

M-R

respectively,

need

inputted

formonthe

print

line70to

70

within

(or

sometimes

100-140,

the

variableNis

we

getNFequaltoM!,R!and

variablesasthey

screen:

form

subroutineina

RETURN

endingonline70has

the

program.

the

same

might

program

Certain

variable)

input

just

that

fixed

are

usedtooutput

and

the

performaspecified

repeatedly

the

following

variables

variableNFis

(M-R)!.

calculates

structure:

are

the

Subroutines

nestedinSUB20.

only

limitisthe

Subroutines

accepts

on

the

subroutines.

CAUTIONS

A

common

and

resultina

that

are

Many

amountofmemory

can

alsobenestedinmore

specific

screen,

characters

mightbecalledonmany

errorinusing

RETURN

M

R

N

SUB100

usedbyother

programs

from

subroutines

WITHOUT

BC

f

NF

subroutines

have

subroutines

available.

than

the

keyboard,

timesinthe

are

called

nestedinsubroutines

one

subroutine.

printsawinking

main

istoallowamainline

GOSUB

ERROR.

PutaSTOPorENDstatementinyour

BC

=

nested

subroutines.

in

An

input

subroutine,

cursor,

program

executiontofall

and

itself

and

prints

intoafollowing

In

this

case,

SUB100

nested

alsoinvarious

subroutines...The

for

example,

the

given

characters

other

subroutine

codetoprevent

is

that

46

this

10

GOSUB

20

RETURN

20

10

15

GOSUB

END

20

RETURN

Sometimes,

just

once,

memory

to

structure

FOR-NEXT

withasingle

The

end

Nested

variable

Exiting

to

assign

We

have

you

might

thenitshouldbeincorporated

space.Onthe

your

program

LOOPS

simplifies

statement.

of the

FOR

names

a

loopisspecifiedbythe

FOR-NEXTIoop

the

maximum

seen

how

routine.

10

1=1

201=1+

30

1

IFI<=10

haveatendency

other

hand,

subroutines

into

blocks.

the

writingofBASIC

loops

are

permitted

resultinNEXT

WITHOUT

viaabranch

limit

to

the

variable

repeated

THEN

operations

GOTO

20

to

make

everything

intoaprogram

are

incredibly

intoasubroutine.

whereitis

programsbyallowing

FOR

I=ATO

statement

as

long

as

FOR

will

leave

the

then

canbeperformed

BSTEPC

loop

errors.

FOR

entryonthe

exit

the

usesaunique

loop

usingacounting

Ifagiven

usedtosave

powerful

programming

onetospecify

variable.

stack.

through

The

a

NEXT.

variable

subroutine

execution

tools

and

complex

best

loop

Use

of

identical

waytohandle

suchasIinthe

is

used

time

and

allow

you

structures

loop

this

is

M

I

j

LI

\ ;

M

|

U

In

this

case,

any

routine

have

values

This

looping

10

20I=

30IFI<=

The

valuesofI

Since

10

20

Iisthe

A,B,C

10

On

the

subscripted

10

20

30

which

process

I=A

l+C

BTHEN

will

this

processiscumbersometouse,

FORI=ATOBSTEPC

may

FOR

other

REM

NF=1

FORI=1TO

variable,

not

onlybeconstants,

I=A(2)+1TOJ*2STEP-1

hand,

1(1,4).

When

COMPUTATIONOFFACTORIAL

appearinginlines

range from1to10in

canbegenralizedinthe

GOTO

range

the

fromAtoBin

Aisthe

counting

the

N

20

variable

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47

40

NF=NF*I

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48

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10

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1

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49

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51

DATA

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NOTES

56

Chapter

As

sideofthe

As

PET

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main

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signal

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1

2

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4

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6

7

8

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10

11

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A

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D

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impedance

Standard

IEEE

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Numbers

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

matchingisin

Mnemonic

IEEE

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DI01

DI02

DI03

DI04

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NRFD

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IEEE-488

#1

specifications.

#2

#3

#4

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RECEPTACLES

A

listoffrequently

edge

card

FOR

THE

used12position,

connectorJ1andJ2is

Table

IEEE

INTERFACE

Table

7.3.

PET

IEEE-488

associated

shown

7.4.

contact

24

contact

here:

Manufacturer

Cinch

Sylvania

Amp

Receptacles

connectorsorparallel

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labels

receptacles

recommended

characters.

characters,

and

descriptions.

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Part

Number

251-12-90-160

6AG0M2-1A1-01

530657-3

530658-3

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for

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user

port.

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are

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their

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7.5.

long

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page.

Digital

Video

usedindiagnostic

the

video

Direct

the

IEEE-488

ing

operationofthe

nostic

Direct

the

IEEE-488

ing

operationofthe

nostic

When

up

the

nostic

routine.

user

characters,

and

their

Signal

Description

ground.

output

used

for

external

routine

circuittothe

connectiontothe

port.Itis

routine.

connectiontothe

port.Itis

routine.

this

pinisheld

PET

software

routine,

port

descriptions.

rather

information.

the

corresponding

display

SRQinthe

EOIinthe

low

jumpstothe

than

display,

for

verifying

board.

SRQ

signal

on

usedinverify

diag

EOI

signal

on

usedinverify

diag

during

power

diag

the

BASIC

59

Table

7.6.

Parallel

user

port

information

(continued).

Identification

Character

6

7

8

9

10

11,

12

A

B

C

D

E

F

H

J

K

L

M

N

Signal

Label

Tape

READ

Tape

READ

Tape

TV.

Vertical

TV

Horizontal

GND

CA1

PA0

PA1

PA2

PA3

PA4

PA5

PA6

PA7

CB2

GND

#1

=2

Write

Description

Used

with

the

diagnostic

verify

cassette

Used

with

verify

cassette

Used

with

verify

operationofthe

tionofboth

TV

vertical

diagnostic.

TV

display.

TV.

horizontal

diagnostic

Digital

Standard

6522VIA.

Input/output

and

entlyofeach

or

output.

Special

Digital

tape=1read

the

diagnostic

tape=2read

the

diagnostic

cassette

sync

Maybeused

signal

maybeused

ground.

edge

sensitive

canbeprogrammed

I/O

pinofVIA.

ground.

Signal

routine

WRITE

ports.

signal

verified

for

verified

forTVdisplay.

input

linestoperipherals,

other

for

to

function.

to

function.

to

func

in

external

in

of

independ

input

VERSATILE

The

linesonthe

(VIA

MOS

The

signals

address

The

parallel

for

the

connection,

shift

register.

A

detailed

port

are

signalsinany

INTERFACE

bottom

Technology

CA1,

PAO-7,

E840.

(Decimal

port

consistsofeight

eight

lines,CA1,

CB2.

This

specification

utilizedbythe

way.

ADAPTER

sideofthe

part

#6522).

and

CB2,

address

which

has

PET

can

mostofthe

for

the

for

Internal

user

port

connector

are

directly

connectedtoa

59456).

programmable

alsobeused

abilities

VIAisbelow.

controls.

for

of

All

Please

originate

bi-directional

other

edge-sensative

CA1,

but

can

signalsonthe

note

fromaVersatile

standard

I/O

also

VIA

that

6522

lines

actasthe

that

the

user

60

Interface

VIA

locatedathexadecimal

PAO-7,aninput

inputs

andavery

handshake

inputoroutputofthe

are

not

connectedtothe

should

avoid

interfacing

Adapter

line

powerful

VIA

user

these

Table

7.7

shows

the

decimal

and

hexadecimal

addressesinthe

PET

associated

with

the

VIA.

Decimal

59456

59457

59458

59459

59460

59461

59462

59463

59464

59465

59466

59467

59468

59469

59470

59471

Hexa-

Decimal

E840

E841

E842

E843

E844

E845

E846

E847

E848

E849

E84A

E84B

E84C

E84D

E84E

E84F

$E840+

0000

0001

0010

0011

0100

0101

0110

0111

1000

1001

1010

1011

1100

1101

1110

1111

Addressed

Output

I/O

Read

Access

Read

Access

Serial

Auxiliary

Peripheral

Interrupt

Output

register

with

handshaking.

PortBData

register.

PortAData

register.

Timer1Counter

byte

WritetoTimer1Latch

low

order

Timer1Counter

order

Latch

initiate

Timer1Latch

byte.

Timer1Latch

byte.

low

and

reset

Writetolow

Timer2butdonot

interrupt.

high

2;

reset

write.

I/O

register

without

for

byte.

WritetoTimer

high

order

count.

order

byteofTimer

Counter

order

Counter

Shift

register.

Control

Flag

register

Enable

for

handshaking.

Location

I/O

port

B.

I/O

port

A

Direction

low

order

high

1

byte

and

low

order

high

order

interrupt.

byte

of

reset

byteofTimer

interrupt

register.

I/O

on

(IFR).

Port

A,

2

PROGRAMMING

Data

lines

PAO-7

usingasoftware

showsapractical

The

programming

drive

the

pins

THE

are

individually

POKE

exampleofinput/output

need

programmedasoutputs,

Table

7.7.

VIA

6522

USER

PORT

programmedtofunction

59459

commandtoplace a

onlybecarried

Decimal

and

selection.

outatthe

and

beginning.

PEEK(59471)

61

Hexadecimal

number

addressesinPET.

for

input or

into

the

From

will

read

outputasrequired.

data

direction

thenonPOKE

all

the

inputs.

register.

59471

Thisisdone

Table

7.8

canbeused

by

to

Command

Statement

POKE

59459,255

POKE

59459,0

POKE

59459,240

Programmingoflines

Table

Binary

Representation

11111111

00000000

11110000

7.8.

Parallel

user

PAO-7

for

port

input/output

Lines

PA0-7

PA0-3

PA4-7

example.

operation.

Mode

Output

Input

Output

SECOND

This

with

A

keying

This

are

CASSETTE

interfaceisbrought

.156

inch

spacing

slotislocated

portisintended

madeatthe

riskofthe

supply.

Table

7.10

shows

typical

receptacles

INTERFACE

out

between

for

use

user.

the

PET

that

are

Insulation

(Connector

from

the

PET

contact

pins

2-3.

with

the

Commodore

Please

identification

suitable

for

FROM

Figure

PET

RearorEdge-on

7.9.

J3)

main

logic

centers

note

(See

that+5voltsisnot

characters,-labels

the

second

MAIN

LOGIC

BCD

View

Simplified

with

viewofedge

contact

boardtoa 6

Figure

second

cassette

7.9).

position,12contact

system

intended

and

descriptions.

cassette

through

identification.

connector.

ASSEMBLY

slotinPET

connector

BOARD

only.

for

Top

View

Upper

Contact

(or

Pin)

Lower

Contact

(or

Pin)

J3

Any

use

as an

Table

edge

connector

other

connections

external

7.11

shows

power

some

Note

A-1,

B-2,

In

some

Identification

Characters

A-1

B-2

C-3

D-4

E-5

F-6

PET

etc.,

special

units,

Label

GND

+5

Motor

Read

Write

Sense

Table

identification

implyapinAto

pins1through6were

Digital

Positive5voltstooperate

Computer

Read

Write

Monitors

7.10.

Second

characters,

pin1,

ground.

only.

controlled

cassette

motor.

line

from

linetocassette.

closureofmechanical

when

cassette

labels

62

pinBto

cassette.

interface

and

pin2,connection.

not

connected.

Description

positive6volts

any

buttonispressed.

port.

associated

cassette

circuitry

for

switch

on

descriptions.

u

Manufacturer

Sylvania

Viking

Amp

Sullins

Cinch

Table

7.11.Aselection

with

the

PET

DAUGHTER

The

PET

main

expansion

suitable

J4

daughter

Daughter

connectors

andJ9are

board

12

3 4 5 6

#

function

-5V

Raw

-5V

Raw

connectorsJ4and

6AJ07-6-1A1-01

2KH6/1AB5

2KH6/9AB5

2KH6/21AB5

530692-1

ESM6-SREH

250-06-90-170

off

suitable

second

BOARD

logic

which

2x25

(row,

power

7

power

key

+12V

Raw

power

+12V

Raw

power

Ground

Manufacturer

Spectra-strip

Circuit-Assembly

Table

7.12.Aselectionofsuitable

for

connecting

connectors

with

J4,

J9,

J10,

Identifier

MEMORY

The

and

7.12

spacing

Note

returns

receptacles

cassette

EXPANSION

board

edge

connector

CONNECTORS

has

been

J9,

and

the

user

column)

configuration,

connections

•

o o••

123456

*

p[

1

+9

key

2

key

3

4

+9

5

ground

6

+9

7

Ground

contact

2x7

2x25

2x7

2x25

PET

grid

daughter

and

J11

board

EXPANSION

memory

decoded

expansion

input/output

showsasimplified

between

that

the40top

for

connecting

J3.

contact

the

corresponding40lower

(J4,

designedtosupportadaughter

expansion

may

attach

power

for

his

and

table

7.13B

lists

table

7.13A

• •

7

function

unregulated

identifier

802-104

802-114

802-050

802-150

CA-14-IDSC

CA-50-IDSC

receptacles

CONNECTOR

connector

lines

viewofthe

centersis0.1

edge

"B"

connections

J9,

J10,

J11)

connectors

own

boards.

J10

and

J11

the

memory

Memory

1

2 3

45678

pin#

SideAl

11

12

13

#

SideAl

10

11

12

13

2

3

4

5

6

7

8

9

10

2

3

4

5

6

7

8

9

function

ground

BA0

BA1

BA2

BA3

BA4

BA5

BA6

BA7

BA8

BA9

BA10

BA11

function

ground

BD0

BD1

BD2

BD3

BD4

BD5

BD6

BD7

SEL2

SEL3

SEL4

SEL5

from

board

J10

All

are

expansion

(ConnectorJ4and

provides

the

80-position

and

connector

2x7.

accesstothe

6502

microprocessor.

connectors

inch.

(or

pins)

edge

"A"

which

attachestomemory

J11.

Table

pins

Table

7.13A

connections.

areon.1"

connections.

bus

9

101112 131415

14

15

16

17

18

19

20

21

22

23

24

25

table

16

#

Memory

SideB1-25

(J4j

#

14

15

16

17

18

19

20

21

22

23

24

25

Side

B1-25

J9

buffered

Figure

used.

The

are

ground

7.12

shows

grid.

lists

the

7.13B

17 1819202122 23 24

function

BA12

BA13

BA14

BA15

SYNC

IRQ

Management

B02

BR/W

DMA

ground

function

SET6

selT

SEL"8

SEL"9

SEL

A

seTb

CAS

RAS

RES

RDY

NMT

ground

0

n

u

I"*

U

25

U

0

63

D

Table

7.13C

shows

the

PET

numbers,

line

labels

and

line

descriptions.

Connector

Numbers

J9-1

J9-2

J9-3

J9-4

J9-5

J9-6

J9-7

J9-8

J9-9

J9-25

J9-10

J9-11

J9-12

J9-13

J9-14

J9-15

J9-16

J9-17

J9-19

J9-21

J9-22

J4-10

J4-11

J4-12

J4-13

J4-14

J4-15

J4-16

J4-17

J4-18

J4-19

J4-22

J4-23

J4-24

J9-1

J4-2

J4-3

J4-4

J4-5

J4-6

J4-7

J4-8

J4-9

J4-20

J4-21

J4-25

Line

Labels

GND

BA0

BA1

BA2

BA3

BA4

BA5

BA6

BA7

GND

BA8

BA9

BA10

BA11

BA12

BA13

BA14

BA15

IRQ

B02

BR/W

SEL2

SEL3

SEL4

SEL5

SEL6

SEL7

SEL~8

SEL~9

SEL

A

SELB

RES

R"DY

NMI

GND

BD0

BD1

BD2

BD3

BD4

BD5

BD6

BD7

RAS

CAS

GND

Logic

Ground

Address

Logic

Address

Interrupt

Buffered

4K

Reset

Ready

Non

Logic

Data

Dynamic

Logic

bit0,used

bit1,used

bit2,used

bit3,used

bit4,used

bit5,used

bit6,used

bit7,used

Ground.

bit8,used

bit9,used

bit

10,

bit

11,

bit

12,

bit

13,

bit

14,

bit

15,

request

phase2clock.

read/write

byte

page

byte

page

byte

page

byte

page

byte

page

byte

page

byte

page

byte

page

byte

page

byte

page

for

6502

linetothe

maskable

ground.

bit0.Buffered.

bit1.Buffered.

bit2.Buffered.

bit3.Buffered.

bit4.Buffered.

bit5.Buffered.

bit6.Buffered.

bit7.Buffered.

RAM

Ground.

Line

Description

for

memory

for

memory

for

memory

for

memory

for

memory

for

memory

for

memory

for

memory

for

memory

for

memory

used

for

memory

used

for

memory

used

for

memory

used

for

memory

used

for

memory

used

for

memory

linetothe

from

6502

address

microprocessor.

interrupttomicroprocessor.

RAS.

CAS.

select

select for

select

select for

select

microprocessor.

expansion.

microprocessor.

for

memory

for

memory

for

memory

for

memory

for

memory

for

memory

for

memory

for

memory

Note:

Buffered.

locations

connectedto74LS00

2000-2FFF.

3000-3FFF.

4000-4FFF.

5000-5FFF.

6000-6FFF.

7000-7FFF.

8000-8FFF.

9000-9FFF.

A000-AFFF.

B000-Bfff.

output.

64

ADDITIONAL

By

this

permits

To

add

flexibility

the

PET,

enhanced

the

useofthese

To

communicate

BASIC

time,

the

outputordisplayofdata.

and

future

flexibility

a)

b)

c)

d)

e)

COMMANDS

userisprobably

to

the

PET

Commodore

of

data

extra

commands.

with

any

device,acombination

OPEN/CLOSE

PRINTS

CMD

INPUT*

GET#

familiar

computer

system,

products

interchange

Openorclose

Write

SameasPRINT*

listener

Read

PET

with

the

These

commands

several

will

take

between

data

from

on bus

data

from

accepts

use

of the

commands

are

commontoall

commands

advantage

the

PET

of

the

logical

PETtoI/O

but

after

I/O

one

character

of

the

and

peripheral

additional

file.

device.

leaves

executionofcommand.

devicetoPET.

from

INPUT

have

been

resulting

and

PRINT.

formsofBASIC.

addedtoclassical

extra

capability.

devicesispossible,

commandsisused:

IEEE

deviceanactive

I/O

device.

INPUT

BASIC

In

thanks

in

general,

to

INPUT/OUTPUT

In

ordertouse

consideration:

These

statement:

LOGICAL

Files

parameters

are

usedtostore

convenient

logical

storage

For

upon

file.Tothe

system

example,

requesttothe

havetoopenafile

PET

can

usea"read"

Whennofurther

COMMAND

the

additional

a)

Logical

b)

Device

c)

Secondary

d)

File-name

can

OPEN#LF,D,SA,FN

FILES

extension

PET

suchasmagnetic

imagine

that

PET

and

dataisrequired

PARAMETERS

commands

file

number

appear,

and

retrieve

of

this

operating

an

via

the

(D)

address

(FN)

for

example,

ideaisto

system,

tape.

external

IEEE

assignalogical

command

(INPUT#)

from

referred

(LF)

(SA)

data,asfor

regard

data

digital

bus.

Sometime

file

numbertorefertothe

which

the

voltmeter,

tointhe

when

using

above,

the

OPEN#

exampleinthe

any

device

might

voltmeter

uses

which

justaswell

is

set

during

the

logical

the

logical

four

parameters

commandinthe

caseofa

can

have

up

so

that

"voltmeter

voltmeter.

file

magnetic

receive

and/or

come

from,orbe

it

can

transmit

program"

Once

number

to

canbeclosed.

mustbetaken

formofthe

tapeordisc

generate

going

voltage

the

programmer

this

has

been

refer

to

the

voltmeter.

into

file.

A

dataasa

to,

a

readings

will

done,

The

More

generally,

the

advantages

a)

Every

device

canbeassociated

withinaprogram.

b)

Multiple

by

meansofdistinct logical

tobeusedinthe

the

PET.

c)

Oncealogical'file

offeredbythe

number

with

files

withinasingle

newly

secondary

its

developed

number

own

useoflogical

address

unique

file

numbers.

has

dev

disc

been

65

ice

logical

canberefered

This

storage

definedinan

files

are:

combination

file

number

to

approach

system

is

for

OPEN

statement,

in

the

need

address

withinaprogram,

following

for

further

(where

only

this

input/output

statements.

restatementofdevice

used)

and

file

name

(where

number

number,

needbeused

This

eliminates

secondary

used).

the

Althoughitis

system

that

range1through

DEVICE

All

for

All

the

cases,aspecific

to

On

of less

hastokeep

canbecontrolledbythe

devices

the

following

other

device

communicate

many

expensive

permissabletoidentify

255.

NUMBERS

which

devices

which

IEEE

the

peripherals:

Number

Default-1Cassette1panel

are

will

number

using

devices,

products,bythe

and

trackofthe

PET

Device

automatically

have

the

files

that

PETatone

communicates

Device

0

Keyboard

2

Cassette2add-on

3

Video

screen

assumedbythe

been

allocatedanumber

wouldbeallocatedtoeach

parallel

allocationofthe

IEEE-488

connectionofjumpers.

use

many

logical

are

currently

timeisten.Alogical

with

are

mounted

in

assigned

PETtobe

within

IEEE

bus.

device

numberismadebymeansofa

filesina

useinthe

file

numbers.

IEEE

the

devicetoallow

given

program,

program.

number

devices,

range4through

The

canbeany

The

first

and

the

greatest

fourofthese

controlistransferred

30.

PET

andaparticular

the

PET

operating

numberoffiles

integerinthe

are

reserved

Exceptinspecial

device

switch,orin

the

case

to

SECONDARY

The

conceptofsecondary

The

useofa

modes.

ADDRESSES

secondary

For

example,ina

address

PET

Secondary

Address

permitsanintelligent

printer,

Operation

Default-0Normal

1

Printing

2

Transfer

3

Set

variable

4

Use

5

Byte

In

short,bychanging

operating

particular

canbeobtainedbyconsulting

The

characteristics

secondary

PET

tape

units

the

secondary

canbetotally

address

haveaspecial

Secondary

Address

conventions

Operation

the

Default-0Tapeisbeing

1

Tapeisbeing

2

Tapeisbeing

tape"

maybenewtothose people

who

peripheraltofunctioninany

there

are

six

secondary

addresses:

printing

under

format

data

from

lines

expanded

data

address

manual

set of

diagnostic

for

programmable

changed,ifso

which

for

secondary

opened

header

being

statement

control

PETtoformat

per

page

messages

character

usedtocommunicate

desired.

mustbefollowed.

that

particular

address

for

forced

device.

rules:

"read"

"write"

when

the

have

never

statement

with a

Manyofthe

Specific

withan"end

file is

given

IEEE

closed.

worked

with

the

oneofa

physical

devices

dataonthese

of

device,

have

conventions

IEEE

bus.

number

their

of

its

own

The

secondary

FILE

NAMES

In

random

filesismandatory.Inthe

facilitates

address

storage

the

devices

identification

can

have

values

where

caseoftapes,afile

thereismore

of

tapes.

over

nameisdesirable,

the

range0through

than

one

filetobe

evenifthereisonly

31.

accessed,

the

useofnamestoidentify

one

fileonthe

tape,

since

it

For the

Whenafile

Assume

be

three

unwanted

It

For

ordertoascertain

TAPE

The

are

It

by

Note

think

Becauseofthe

and

simultaneously

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IEEE-488

status

an EOI

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command,

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output

number,

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system

systems.

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device.

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5

file

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logical

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For

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IEEE-4888

the

devices,

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DEVICE

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DETECTION:

basic

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the

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for

all

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Table

7.17

shows

operations,

tape

timebycalling

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the

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verify

and

ST

Bit

Position

0

1

2

3

4

5

6

7

meaning

functionoftheSTword

load

operations.

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Numeric

Value

-128

1

2

4

8

16

32

64

the

function

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in

the

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bitinthe

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value

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the

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line

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three

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Table

7.17.

Status

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tape

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terminates

attention,

unit

occur

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bus

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than

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only

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lost.

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.

100

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110

PRINT

120IFST=0THEN

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100

INPUT#2,A,B,C

110IFST=0

120IFST=64

technique

the

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A

the

THEN

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200

transferofdata

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print

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300

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logical

than

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value

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the

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TECHNIQUES

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PARAMETERS

Statement

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IEEE-488

INPUT#

from

devices

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Parameter

Device

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address

1

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1,2,1

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that

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real

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•

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Parameter

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OPEN^1,2,0

OPEN#1,2,1

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information.

seriesofslow

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SA=0

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suchassampling

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INTRODUCTIONTOTHE

This

bus

consistsof16

a)

The

data

2)

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control

3)

The

management

Furthermore,

the

IEEE

bus

a)

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datatothe

b)

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simultaneously

c)

Controller:

Table

IEEE-488

signal

BUS

lines

that

transmission

bus

can

support

given

data

bus.

devicesasrequired

from

the

PETisthe

7.19.

Exampleofdefault

are

divided

bus

three

classesofdevice:

moment,

only

bus.

only

controller

parameters.

functionally

one

deviceispermittedtotransmit

may

82

into

three

receive

data

allowedonthe

groups,

IEEE

bus.

those

are:

BUS/DEVICE

The

line-pin

assembly

Certain

CONTROL

connections

board

physical

for

the12position,24contact

(see

Table

7-19).

limitations

a)

The

b)

The

c)

The

shouldbenoted

maximum

edge

For

further

advisable

interdevice

information,

when

bus

extension

spacingis5

please

connecting

from

meters.

numberofdevicesis15.

card

connector,

refertoFigure

devicestothe

the

PETis20

emanate

from

7.2

IEEE

bus:

meters.

the

PET

u

0

main

u

0

PET

Contact

Identifi

cation

1

2

3

4

5

6

7

8

9

10

11

12

A

B

C

D

E

F

H

J

K

L

M

N

Bus

DATA

MANAGER

TRANSFER

MANAGER

DATA

MANAGER

GROUNDS

IEEE

Label

DI01

DI02

DI03

DI04

EOI

DAV

NRFD

NDAC

IFC

SRQ

ATN

SHIELD

DI05

DI06

DI07

DI08

REN

GND6

GND7

GND8

GND9

GND10

GND11

LOGIC

GND

PET

Contact

Identifi

cation

1

2

3

4

5

6

7

8

9

1*0

11

12

13

14

15

16

17

18

19

20

21

22

23

24

Label

Description

Data

INPUT/OUTPUT

Data

INPUT/OUTPUT

Data

INPUT/OUTPUT

Data

INPUT/OUTPUT

Endoridentify

Data

valid

Not

ready

for

Data

not

Interface

SameasPET

Service

Attention

Chassis

cable

Data

Remote

groundinthe

DAV

NFRD

NDAC

IFC

ground

SRQ

ground

ATN

Data

ground

data

accepted

clear

reset

request

ground

and

shield

INPUT/OUTPUT

enable

(REN)

PET

ground

(DI01-8)

LINE

IEEE

LINE

always

#1

#2

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=±5

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0

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U

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0

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Table

THE

DATA

This

busiscomprisedof8

slowest

one

byteata

Peripheral

differentiated

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most

Foranexplanation

Data

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possible

THE

TRANSFER

This

three

BUS

deviceinuseonthe

time,

bit

parallel.

addresses

and

from databyATN

significant

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bit

line

bus

bit

of

signal

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patterns

BUS

controls

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are

7.20.

IEEE

bus

group,

bi-directional lines

busata

control

abbreviations

validonthe

the

given

time

information

(true)

during

line

are also

their

DI08.

suchasDI-08,

data

bus

transfer

of

data

label

and

contact

that

transmit

controls

the

transmitted

transfer.

when

sending

over

the

data

83

identification

the

active

rateofdata

see

Figure

number.

low

data

transfer;

on

the

data

7.23.

datatodevices.

bus.

The

signals

the

bus.

transmitted

D101-8.

The

modeoftransfer

They

are

used

is

in

u

0

the

handshake

procedure

outlinedin7-21,

These

Note

See

The

Whenatalker

ensure

The

interconnection

The

showninthe

signals

that

Table

Handshake

are:

a)

b)

c)

the

talker

7-23

for

NRFD

NDAC

DAV

originates

detailed

Procedure

transmits

that

the operationissuccessful.

essential

transferofdata

functionofthe

a)

All

listeners

b)

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thereisvalid

c)

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the

occursata

of

devices

sequenceofevents

flow

diagramoffigure

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ready

for

Data

not

accepted

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valid

the

DAV

description

a

data

bytetooneormore

of

handshakeisto

are

readytoaccept

dataonthe

data

has

been

rate

determinedbythe

which

that

handle

occur

during

7-21.

data

signal

and

the

listeners

signals.

listeners,

ensure;

data.

data

bus.

acceptedbyall

listeners.

slowest

dataatdifferent

the

transferofa

speeds.

data

the

NFRD

this

control

active

deviceonthe

byte

from

and

NDAC

procedureisusedinorder

the

talkertothe

signals.

bus;

this

allows

listeners

to

the

is

Not

NRFD

(Listener)

DAV

(Talker)

NDAC

(Listener)

Data

Bus

Signals

Settling

Greater

(2)'

Data

Signal

Interval

than64msec.

(5) (7)

Ready

for

Data

Not

Ready

Data

Not

Valid

Data

Valid

Data

Accepted

Data

Not

Accepted

Bit

High

Bit

(Being)

Value=0

Impedance

Value=1

for

Data

Figure

7.21.

Transfer

bus

handshake

84

sequence.

COMMENTS

TALKER

COMMENTS

All

Listeners

are

Ready

for

Data

Is

the

Data

Valid

Data

Not

Valid

Figure

7.22.

listners.

Sequenceofevents

Broken

lines

duringadata

indicate

byte

the

testingoftransfer

transfer

bus

from

the

signal

logic

Not

ready

for

Data

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Not

Accepted

talkertothe

levels.

85

Figure

7-22

shows

numbersinthe

1)

signalstosettle.

3)

DAV

4)Assoonasa

NRFD

rate,

5)

the

6)

invalid.

7)

low

the

data

required

the

relative

following

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byteofdata.

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talker

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talker

low

low;

each

NDAC

data.

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talker

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listeners

(true)

data,

transfer.

data

timingoftransfer

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(false)

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indicating

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listeners

single

listener

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note

release

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repeat

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again,

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listener

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the

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Figure:

afterorduring

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that

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processed

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(1).

all

bracketed

PET/IEEE

The

If

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THE

This

concerned

The

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following

limitations

Table

7-24.

MANAGEMENT

groupoffive

with

five

management

Timing

limitations

a)

afterithas

b)

afterithas

a)

b)

c)

d)

e)

Constraints

shouldbenotedinordertoavoidalossofdata:

When

data,

PETisa

set

NFRD

When

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set

NRFD

are

exceeded,

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signal

ATN

EOI

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lines

controls

addresses,orcontrol

signals

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identify

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clear

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request

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are:

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,

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SIGNALS

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DEFINITIONS

linesofthe

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7-23

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businthe

LEVEL

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Functional

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PET

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low

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bus

devicetohold

the

Table

continuedonnext

Table

page.

7.23.

IEEE-488

87

bus

signal.

Table

7.23.

IEEE-488

bus

signal

(continued).

STATUS

STisa

have

IEEE-488

WORD

BASIC

certain

bus.

Group

Data

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variable

values

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over

ST

1

2

64

-128

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through

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The

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milliseconds

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8

the

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PETtoBASIC

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PEEK

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hardware

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E820

E822

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7.25.

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59424

59426

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59427

59408

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hardware

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time

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3

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6

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addresses

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NOTES

90

Chapter

8.

USEOFTHE

PET

FOR

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LANGUAGE

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92

Commodore CBM 2001-16N, CBM 2001-16, CBM 2001-32, CBM 2001-32N User Manual

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