Commodore 2040, 3040, 4040, 8050 User Manual

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Page 1

User's

for

Manual

CBM

5Y4-inch

Dual

Floppy Disk

Drives

ell

commodore

Page 2

User's

for

Manual

CBM

Dual

Floppys

Model Model

Appropriate

Commodore

•

Series Series

•

Series

•

Series

Part Number 320899

2040-Model 4040 3040-Model 8050

2001 3000 CBM) 4000 8000 CBM)

Drive

for

use

Computers

(CBM-PET)

PET)

with:

October 1980

(I[

commodore

Page 3

Chapter 1

Table of Contents

Introduction.

General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Care Of The 2040, 3040, 4040 and 8050 . . . . . . . . . . . . . . . . . . . . 9

Care Unpacking The Disk Drive 9

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Front Panel 3 Back Panel 3 Interior Configuration 4

The Diskette . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

The Diskettes 9

Page

Chapter 2

Chapter 3

Preparing To

Connecting The Disk Drive To The Computer 11 Performing The Power-On Test 12 Inserting The Diskette Into The 8050 13

Learning How To

The Block Availability The Disk Operating System (DOS) , 22

Disk Maintenance Commands. . . . . . . . . . . . . . . . . . . . . . . . . . .

Use

Your Disk Drive 11

Inserting The Diskette Into The 2040, 3040 and 4040 The 4040 and 8050 Performance Test 14 The 2040 and 3040 Performance Test 17

Use

Your Floppy Disk Drive

Map

(BAM)

NEW

HEADER (BASIC 4.0 Direct Command) . .

Initialization (2040 and 3040) . . . . . . . . . . . . . . . . . .

Initialization (4040) . . . . . . . . . . . . . . . . . . . . . . . . . .

Initialization (8050) . . . . . . . . . . . . . . . . . . . . . . . . . .

The Directory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

LOAD$ 26

DIRECTORY (BASIC 4.0 Direct

Printing The

Directory.

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

Command).

21 22

26 27

iii

Page 4

VALIDATE..................................

COLLECT (BASIC 4.0 Direct Command). .

DUPLICATE 28

29 29

COpy

BACKUP (BASIC 4.0 Direct Command). . . COpy

(BASIC 4.0 Direct Command) . . . . .

CONCAT (BASIC 4.0 Direct Command). . .

RENAME 31

RENAME (BASIC 4.0 Direct Command) . .

SCRATCH 32

SCRATCH (BASIC 4.0 Direct Command). .

Chapter 4

Chapter 5

BASIC Commands For Data Handling 35

BASIC Commands Associated with Floppy Disk Drives . . . . . . .

SAVE and DSAVE (Writing a Program

a Diskette) .

LOAD and DLOAD (Reading a Program from a

Diskette) 36

VERIFy.....................................

37 OPEN 38 DOPEN 39

CLOSE......................................

39 DCLOSE 40 Closing The Command Channel 40 Closing The Data Channel 41

PRINT# . . . .

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

.. ..

41 INPUT# 42 GET#

43 RECORD# 43

Quickload Feature (BASIC 4.0)

Moving a Tape Program

Disk 45

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

Advanced Disk Programming 47

Commodore Disk Operating System (DOS) 47

Disk Utility Command Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

BLOCK-READ................................

BLOCK-WRITE. . . . . . . .

......

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

. . .

50 BLOCK-EXECUTE 50

BUFFER-POINTER . . . . . . . . . . . . . . . . . . . . . . . . . .

BLOCK-ALLOCATE "

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

MEMORy 51

MEMORY-WRITE

MEMORY-READ. . . . . . . . . . . . . . . . . . . .

MEMORY-EXECUTE 52

USER.......................................

8050

Disk Zones 59

Chapter 6

Advanced File Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Special Open and Close Statements For Direct Access . . . . . . . .

Random Access Example . . . . . . . . . . . . . . . . . . . . . .

To Create A File . . . . . . . . . . . . . . . . . . . . .

To Add A

Record.

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

To See A Record 68 To Change A Record 68

Getting The Directory of Listings . . . . . . . .

Page 5

Ending The Program . . . . . . . . . . . . . . . . . .

Relative Files 4040, 8050 . . . . . . . . . . . . . . . . . . . . . .

Creating A Relative File Expanding A Relative File 72

Accessing A Relative File . . . . . . . . . . . . . . . . . . . . . .

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

Chapter 7

Chapter 8

Chapter 9 Chapter 10

Simplifying The

Loading The Using The Loading A Program With The Loading And Running A Program With Special

Error Messages - Pattern Matching File Names - Disk Commands. . .

Requesting Error Messages: Commodore Disk Drives. . . . . . . . .

Summary Of Description of Pattern Matching 85

User's Quick Reference: Disk Commands. . . . . . . . . . . . . . . . . .

Random 1.00 Program Listing 89

Index , . . . . . . . . . . . . . . .

Use

of Commodore Disk-Related

DOS

Support Program . . . . . . . . . . . . . . . . . . . . . .

DOS

Support Symbols: >and @ . . • • . • • . • . • . • • . •

Commands.

. . . . .

1. ... . . . . . . . . . . . .. . . . . . . . . .

Arrow... . . . . . . . .

DOS

Support Information 79

CBM

Floppy Error Messages 82

DOS

Error Messages 82

List of Illustrations

Figure Title

1 Models 2040, 3040, 4040, 8050: Rear View 5 2 Floppy Disk Hookup 12 3 Position For Diskette Insertion 13 4 5 8050 Format: Expanded View of A Single Sector 63

2040,3040,4040

Format: Expanded View of A Single Sector 62

.•

Page

List of Tables

Table Title

1 Suggested Reading List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2 Specifications: Model 8050 Dual Drive Floppy Disk 6 3 Specifications: Models 4 Specifications: Model 4040 Dual Drive Floppy Disk 8

5 Standard Jump Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6 Block Distribution 7 8

9 4040 10 11 8050 Directory Header 12

2040,3040 2040,3040

BAM

4040 Directory Header. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8050

BAM

BAM Directory

Format.

2040/3040 Dual Drive Floppy

Track 54

Format.

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

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

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

Header.

Block.

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

Disk.

. . . . . . . . . 7

Page

Page 6

Directory Sequential Format Program File Format Relative File Format 70 User's Quick Reference - Disk Commands 87

Format.

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

61 61

Page 7

Chapter

INTRODUCTION

The disk-oriented Commodore Computer System of providing you, the user, with large file-handling capabilities supported by gramming commands and further simplified by

Read the Table of Contents and become acquainted with the broad scope of material

covered

gram by utilizing the computer drive ment of the system tionship

That's why it Grasping and understanding the concept that each individual component acts and reacts to signals and commands from other devices in the system will greatly accelerate your fundamental grasp of how the basis of this manual: teaching you how to gain mastery of the system so that it will

perform as desired. That fashion: it permits you

The first chapters discuss basic hardware features and permit you, right from the start,

become familiar with the disk drive by doing the performance tests which comprise the first

essential "hands learning

more comprehensive subjects.

this manual.Ithas been designed to assist you in pursuing an educational pro-

an adjunct to the learning process. That is, once the disk

properly interfaced to a Commodore Computer,

the hardware. Your importance, however,ismeasured in direct rela-

how well you understand howtoeffectively utilize the hardware and software.

besttothink of your computer and disk driveasonly part of a system.

operate, control, and master the system. This basic concept forms

the primary reason this manualislaid

advanceasfast as you desire.

on"

experience. Then, by actually using your particular disk drive and

carefully follow instructions, you can gain confidence in order to proceed

was

designed around the central concept

DOS

Support command abbreviations.

YOU

become as important an ele-

outina building block

BASIC

pro-

the time you begin Chapter 3-Learning How To have already used some portions of the until Chapter 7. The reason for this procedure lies within the purpose of simplifying commands. command structure of archy at an early stage. This concept of providing you with enough essential information complete a task, a step-by-step description of the task, and meaningful examplesisa feature of this manual which will provide you with sufficient incentive to actually complete the task.

actually easier to instruct a new user by using the simplified

DOS

Support than attempting to explain the entire command hier-

DOS

Support system whichisnot fully described

Use

Your Floppy Disk Drive-you will

DOS

Support:

Page 8

The manner in which this manual Difficult concepts and procedures have been broken down through examples which provide ample each command description. When possible, command description and,asan Chapter 8 for easy access if problems persist.

laid

out

encourages

opportunitytoexperiment laterbyreturning

the

command

additional aid, a User's Quick Reference has been placed in

the

conceptoflearningbydoing.

into

steps

that

walk

the

user

format

has been included with

the

Error messages are also presented in Chapter 8 where needed. The Error Message discussions have been expanded

• How

• Error message summary.

• Detailed error message descriptions.

For

those users who have been reluctanttoattempt sumed degree manual from least difficult

• Commands for file manipulation and maintenance

• Commands for

• Advanced programming

• Advanced file handling

• Simplified commands

Users who have advanced subjects such as random access or relative files while others may be just following the

user with essential information in a logical sequence. Follow

step-by-step procedures, and learnbydoing.

With

the

computing powerofyour

should study

1. You will benefit most if

Table

those features CBM

Floppys.

request error messages.

difficulty,

data

attained

the

manual's format. In either case, this manual has been laid

purchaseofyour

your

computer's

that

relatetoyour

note

that

the

entire disk command hierarchyisstructured in this

more complex:

handling

some degreeofprogramming skills may desiretobegin with

Commodore Dual Drive

Commodore system.

user guide, and if necessary

you

first read through this entire manual, taking

particular floppy as well as those which are

they

can be quickly referenced, if

include:

disk programming becauseofthe

the

examples,

GENERAL

Floppy

get

Disk the the

you most BASIC manuals listed in

INFORMATION

have greatly enhanced

outofyour

pre-

the

content

outtoprovide

attempt

commontoall

system

note

with

the

you

The information presented in this manual is extensive and may, in some cases, present in-

formation and thoughtfully studying its

sively upgrade

This manual presents discussions, descriptions, practices and procedures relating and operation

Four

thatiscurrently

your

programming skills and expertise.

all Commodore 5-1I4-inch Dual

models are discussed: Model Model Model Model

2040 3040 4040 8050

(DOS (DOS (DOS2) (DOS 2.5)

beyond

contents

your particular levelofexpertise. However, by carefully

you

will gain

the

Floppy

confidence necessarytoprogres-

Disk Drives.

the

use

Page 9

The floppys are operationally compatible with the following Commodore Computers.

1. Series 2001

2. Series 2001 - PET 8K - Upgraded to BASIC Version 3.0

3. Series 3000 - 16K and 32K - Operating

4. Series 4000 - PET 8K, 16K, and 32K - Operating

5. Series 8000 - 32K - Operating For ease of reference, the Models 2040,

Disks will and noted otherwise.

-16K

referred to in this manualas"the

"the

8050", respectively.

and 32K - Operating With BASIC Version 3.0

With

BASIC Version 3.0

With

BASIC Version 4.0

With

BASIC

All

descriptions and discussions are common unless

Version 4.0

3040,4040,

2040",

and 8050 Dual Drive Floppy

"the

3040",

"the

4040",

DESCRIPTION

All

CBM

Floppys describedinthis manual are dual-drive diskette storage devices. Their individual primary components consist of read/write controls, drive motor electronics, two drive mechanisms, two read/write heads, and track positioning mechanisms. discussed is

an "intelligent" peripheral, their operation requiresnospace in the computer's memory. This means you have just have the disks attached.

this manual conform to IEEE-488 interface requirements. Because each device

much computer memory availabletoyouaswhen you do not

All

disk drives

Front Panel

The front panel of the respective disk drive consists of an identification panel across the top;

slots

the doorisclosed, the disketteisclamped onto the diskette spindle hub. Also on the front

panel are three LED indicator lights. The one on the right cator, and lights when drive 0 the 8050, the LED in the middleisa two-color power/error indicator. Itisnormally green, indicating power 4040 the middle LED occurs.

whichtoinsert two diskettes; and doors to close after inserting the diskettes.

called the Drive 0 Active Indi-

active. The LED on the left does the same for drive 1.

but flashes red whenever a disk error occurs. On the 2040, 3040, and

activated if powerisapplied or removed, and whenever an error

When

Back Panel

The back of each disk drive contains an IEEE-488 interface connector. Near the panel's

lower edge

power cord.

the power ON/OFF switch. Thereisalso a "slow blow" fuse, and the

Page 10

Table 1. Suggested Reading List

ICBM Personal

Pet

Computer

Guide. C.S.Donahue andJ.K. Enger, Osborne/McGraw-Hill, Berkeley,

94710

Hands-On Basic with a Pet.

H. D. Peckham,

McGraw-Hill,

1979

Entering BASIC.

J. Sack and

BASIC: A

Pegels, Holden-Day, Inc.,

Computer

Meadows, Science Research Associates,

Programming Language.

1973

BASIC Programming.

J. Kemeny and T. Kurtz,

3100), Menlo Park, CA

BASIC

FOR

HOME COMPUTERS.

Albrecht, Finkle

3100), Menlo Park,

A Guided

TourofComputer

T. Dwyer,

Houghton Mifflin Co.,

Peoples

94025,

and

Brown, Peoples

94025,

Programming in BASIC.

Computer

1967

Computer

1973

Programing Time Shared Computer in BASIC.

Eugene H. Barnett,

Programming Language

Digital

101 BASIC

Equipment

Computer

Software Distribution Center,

Wiley-Interscience, LIC 72-175789

#2.

Corp., Maynard,

01754

Games.

Digital

Equipment

WhatdoTo After You Hit Return.

Peoples

Computer

Co.,

1010

Doyle (P.O. Box

Basic BASIC.

James

WORKBOOKS

T.I.S., P.O. Box 921, Los Alamos,

Programming

R. Zaks,

Coan, Hayden

1-5.

the

6502.

Sybex,

1978

Book

Co., Rochelle Park, NJ

87544

24 Tested, Ready-to-Run Game Programs in Basic.

Tracton, Tab Books,

1978

Some Basic Programs.

Borchers and R. Poole, Osborne & Assoc. Inc.,

Basic Programming for Business.

H. Forkner, Prentice-Hall,

1977

The Channel Data Book.

B. Lewis,

PET and

Osborne/McGraw-Hill,

the

5960

IEEE

Mandarin Ave., Goleta, CA

488

Bus (GPIP).

630

Bancroft Way, Berkeley,

93017,1978

Co.,

1010

Co.,

1010

Corp., Maynard,

3100),

1978

630

Bancroft Way,

1973

Doyle (P.O. Box

Menlo Park,

94710

01754

94025

The interiorofyour

tained within

disk spindles.

floppy contains two disk drives. All

the

unit. The mechanical devices are, for

Interior Configuration

the

logic for

the

most part, located beneath

the

disk drive is con-

the

Page 11

The Diskette

The diskette (also knownasa minifloppy, floppy diskette, minidiskette, etc.)issimilar the standard flexible disk. There are several reputable manufacturers of the 5 1/4-inch diskettes. You should make sure that you buy diskettes for SOFT SECTORED FORMAT. Your Commodore dealer can supply your needs.

Specifications

Table 2 presents the specifications for the 8050, Table 3 the specifications for the 2040 and 3040, and Table 4 the 4040.

Figure 1 - Models

2040,

3040,

4040,

8050:

Rear View

Page 12

STORAGE:

Total

capacity Sequential Relative

Directory Sectors Bytes

per Tracks Blocks

IC's:

Controller

6502 6530 6522

Interface

6502 6532 6564

entries

per

sector

(2) (2)

Table

2. Specifications: Model

track

8050

Dual Drive

533248 521208

bytes bytes

per per

464312to517398

depending

182880 65535 224

per

records

upon

bytes diskette

per

23to29

256

77 2083

microprocessor I/O,

RAM, ROM

I/O,

interval

microprocessor I/O,

RAM, interval

RO~v1

timers

Floppy

diskette diskette

bytes

file size.

file

timers

Disk

per

diskette

Shared

6114

(8)

PHYSICAL:

Material Dimensions

Height Width Depth

ELECTRICAL:

Power

MEDIA:

Diskettes

requirements Voltage Frequency

Power

4x1K

RAM

gao

steel

6.5/1

15.0/1

14.35/1

100,117,220, 50or60 50

Standard

single

Hertz

watts

mini 5

density

1/4",

240

VAC

single sided,

Page 13

Table 3. Specifications: Models

STORAGE:

2040/3040

Dual Drive Floppy Disk

Total capacity Sequential

Random Directory entries Sectors Bytes

per

sector

Tracks

Blocks

IC's:

Controller

6504 6530 6522

Interface

6502 6532

(2)

6332

(2)

Shared

6114

(8)

PHYSICAL:

track

176640 170180 170850

152

17to21

bytes per diskette bytes per diskette bytes per diskette

per diskette

256

35 690

microprocessor

I/O, RAM, ROM

I/O, interval timers

microprocessor

I/O, RAM, interval timers

ROM

4xlK

RAM

Material

Dimensions

Height Width Depth

ELECTRICAL:

Power requirements

Voltage Frequency

Power

Power requirements

Voltage

Frequency

Power

MEDIA:

Diskettes

(2040)

(3040)

gao

steel

6.5"

15.0"

14.35"

120

VAC

Hertz

50 Watts

100,

220,or240 VAC

Hertz

Watts

Standard mini 5

single density

1/4",

single sided,

Page 14

STORAGE:

Table4.Specifications: Model

4040

Dual Drive

Floppy

Disk

Total capacity Sequential Relative

Directory entries

6504 6530 6522

6502 6532 6332

6114

per

sector

(2) (2)

(8)

Sectors Bytes Tracks Blocks

IC's:

Controller

Interface

Shared

PHYSICAL:

track

174848

168656

167132 144

17to21

65535

per

bytes

per

bytes

per

bytes

per diskette

records

diskette

diskette diskette

per

file

256

35 683

microprocessor I/O,

RAM, ROM

I/O, interval timers

microprocessor I/O, RAM, interval timers ROM

4x1K RAM

gao

Material Dimensions

Height

Width

Depth

ELECTRICAL:

Power requirements (4040) USA (domestic)

Voltage Frequency

Power 50 Watts

Power requirements (4040) (international)

Voltage Frequency Power 50 Watts

MEDIA:

Diskettes Standard mini 5

15.0"

14.35"

120 60

100,220,or240 VAC 60

steel

6.5"

VAC

Hertz

single density

1/4",

single sided,

Page 15

CARE OF THE 2040, 3040, 4040 AND 8050

The disk drive should be placed on a flat surface free of vibration. Itisimportant that dust particles be kept at a minimum since a particle buildup will interfere with optimum opera-

tion. attempt

you should experience a hardware failure contact your Commodore dealer. Any

correct the problem yourself could result in voiding the warranty.

CARE OF THE DISKETTES

Handle diskettes with care. Follow these instructions to maintain the quality of the diskette and

protect the integrity of the data:

1. Return the diskette to its storage envelope whenever it

Keep the diskettes away from magnetic fields. Exposuretoa magnetic field can distort the data.

3. Never leave a diskette on top of your computer or disk drive.

4. Do

6. Do not touch or attempt to clean the diskette surface. Abrasions will cause loss of stored

7. Before applying power

not

write on the plastic jacket with a lead pencil or ball-point pen.

or fill out the label before attaching it Do

not expose diskettestoheat or sunlight.

data.

the 2040, 3040, or 4040 open the drive doors and remove

diskettes.

the jacket.

removed from the drive.

Use

a felt tip pen

UNPACKING THE DISK DRIVE

Before unpacking the disk drive, inspect the shipping carton for signs of external damage.

the cartonisdamaged, be especially careful when inspecting its contents. Carefully remove

all

packing material and the contents of the carton. until you have made sure you have located all the contents of the carton! The carton should contain:

NOT discard any packing material

1. Commodore Dual Floppy Disk Drive

2. User Manual, Number 320899

3. One of the following TEST/DEMO diskettes: a. 2040/3040/4040 TEST/DEMO diskette, PIN 4040037 b. 8050 TEST/DEMO diskette, PIN 8050050

any items are missing, please contact your Commodore dealer immediately.

Page 16

Chapter

PREPARING

YOUR

Before starting to use your disk drive, make sure itisin good working condition. This in-

cludes properly connecting it test, and finally the performance test using the appropriate TEST/DEMO diskette.

CONNECTING THE DISK DRIVE TO THE COMPUTER

One of two connector cables are requiredtointerface the floppytothe computer. These cables can be supplied by your Commodore dealer.

PET-to-IEEE cable, PIN 320101 Use

this cable if the disk driveisto

computer.

2. IEEE-to-IEEE cable, Use

this cable if your disk driveisto pheral device such printer.

the Commodore Model 2022, or any other suitable interfaced

your computer,

be the only (or first) IEEE device connectedtoyour

905080

be connected ("daisy-chained") to another peri-

DISK

giving

it a power-on and initial checkout

USE

DRIVE

NOTE: The disk drive should be the first peripheral attached vices are

Follow these steps STEP 1: Turn power OFF STEP 2: Place the disk drive in a convenient location

STEP

STEP 4: Connect the disk drive power cable to an

be "daisy-chained".

connect the disk drivetoyour computer:

the computer.

closeaspossibletothe computer.

NOT connect the disk drivetoa power outlet at this time.

Connect the PET-to-IEEE cable between the IEEE-488 interface connector on the

outlet.

computer and the connector on the disk drive.

connected, the IEEE-to-IEEE cable(s) must be used.

this time.

the computer if other de-

additional IEEE devices are

NOT turn on power at

Page 17

Floppy

Disk

IEEE-la-IEEE

(PIN 905080)

Prinler

Figure 2 - Floppy Disk Hookup

PERFORMING THE POWER-ON TEST

You are now readytoproceed with the power-on part of the checkout:

Cable

STEP 1: Open both disk drive doors. Ensure that no diskettes are present in either drive. STEP 2: Turn power STEP 3: Apply power to the disk drive.

panel will flash twice. On the 8050, the two drive LEDs will two-color power/error LED will stay green indicating power ON. lights remain on, more than five seconds, turn the power OFF. any light remains lit, or

ONtothe COMPUTER and verify that itisworking properly.

All

three indicator lights (LEDS) on the front

out

and the center

the drive

all

lights flash continuously, or if the power/error LEDisred for

Wait

one minute and

all

lights flash continuously, contact your Commodore

try

dealer immediately.

NOTE:

the problem persists,

bus. This should assure that a problem related

try

disconnecting the other devices attachedtothe IEEE

another device does not affect the disk

drive.

again.

Page 18

INSERTING THE DISKETTE INTO THE 8050

STEP 1: Insert the diskette into the slot designated "Drive0"and with the write protect

tab oriented

STEP 2: Once the diskette

tinct "clock". The diskette

Press

STEP

DOWN into the correct position. It motion

To remove the diskette, press release the spring and raise the diskette. ing, press

front

the left.

in the slot, push gently on the diskette until you hear a dis-

now properly positioned in the drive.

firmly on

avoid damaging the diskette.

on the door. This will release the diskette and push it

the drive. The diskette is now free to be removed from the drive.

the

spring-loaded door of the drivetolower the diskette

importanttopress firmly on the door in a smooth

DOWN

firmly on the spring-loaded door. This will

When

the disketteislevel with the open-

out

toward the

STEP 5:

NOT ATTEMPT TO CLOSE THE DOOR WITHOUT A DISKETTE IN PLACE. The doorislocked open by a mechanical interlock mechanism associated with the diskette ejector that prevents the door from closing if no diskette has been loaded.

I-

eI:

WRITE

PROTECT

NOTCH

WHEN COVERED, DISKETTE

CONTENTS

CANNOT

BE ALTERED

••

•

Figure 3 - Position for Diskette Insertion

INSERTING THE DISKETTE INTO THE 2040, 3040 AND 4040

CAUTION: NEVER APPLY POWER TO THE DISK DRIVE IF DISKETTES ARE PRESENT (LOCKED AND SEATED) IN EITHER DRIVE 0 OR DRIVE

STEP 1: Ensure that the powertothe disk driveisOFF and

STEP 2:

you complete this step. Open diskettes are present in either drive.

the preceding conditions have been met, you may apply powertothe disk

drive.

both

disk drive doors and make sure

NOT apply power until

that

Page 19

STEP 3: Insert the diskette into the slot marked "Drive0"and with the write protect tab

oriented

the left. STEP 4: Once the diskette STEP 5: Press

STEP 6: To remove the diskette, insert your index finger under the lip of the spring-loaded

DOWN tinct "click". The diskette ing by the computer.

door and gently PULL. This will release the door and permit access ette. The diskette

isinthe slot, gently push on it until itisfully seated.

firmly on the spring-loaded door of the drive until you hear a dis-

now locked and seated in drive 0, ready for process-

the disk-

now freetobe removed from the drive.

THE 4040 AND 8050 PERFORMANCE TEST

When

you have successfully completed the Power-On test, proceed with the Performance

Test. Don't worry if you don't fully understand exactly what

this point, enter the commands just EXPECTED results are obtained during any step of the test, stop and start over again. The most likely cause of a problem until you become familiar with your disk unit.

All

commands are entered

press the RETURN key on your keyboard.

via

the keyboard and must be followed by a carriage return:

get a feel for what you can do with your disk.IfUN-

an improperly entered command. Thisisto

happening in this test. At

be expected

NOTE: Commands must be entered exactly shown in the example. example anyway. Re-enter your last command. If the light goes out, your correction was successful and you may continue.

NOTE FOR BUSINESS KEYBOARD USERS ONLY: You can set your computer for upper case character entry.

POKE 59468,12 and pressing the RETURN key.

Although itisnot absolutely necessarytogive In addition, the examples in this manual can be duplicated exactly when you use only

upper case. shift key when entering commands. (POKE 59468,14 will return the user

STEP 1: Insert the STEP 2: Type: LOAD

this stepisomitted the display will be in lower case letters.

from the diskette in drive 0 and display the following:

the error indicator lights, you may be abletocontinue the

this by typing:

DEMO

diskette into drive 0aspreviously instructed.

"*",8

and press RETURN. The computer will load the first file

shown.

this command, it does permit easy entry.

NOT insert any spaces unless

lower case letters.)

NOT use the

Page 20

STEP

3: Type: RUN and press RETURN. This

executed. (This program simplifies the direct mode commands.) A brief introductory descrption of Supportispresented in Chapter 3asit applies to Chapter 3 operations. A detailed description of

STEP

4: Insert a blank diskette into drive 1 and type:

>N1:DEMO,99 >C1=0

not necessary for the disk unittooperate; it just

DOS

Supportispresented in Chapter

will

cause the

DOS

Support Programtobe

DOS

This procedure formats the diskette and copys all files from drive 0 thus creating a backup of the drive 0 and return it to its protective envelope. Remove the diskette from drive 1 and place it in drive

STEP

5: Type:

The screen will display:

<:,EAF'CHmCT LORD PERD'T'

~JCT

•

LOAD

FOF'

"PERFORMANCE TEST",8

F'EF'FOFr'1AtJCE

•

STEP

6: Type: RUN and press RETURN.

The program instructs you to place a blank diskette into each drive. The Performance Test Program executes a shortened version of the test used by Commodore in final inspection of the 4040 or 8050. The purpose of this test

that the unit to complete.

NOTE: Do not use diskettes containing any valuable information since the Performance Test Program program will label these diskettes "Test Disk ettes are ready for further use when the test program formance test has been satisfied.

functioning correctly and

DEMO

Close the door to drive

E':,T

will

re-format them and any data

diskette. Remove the

DEMO

diskette from

will

take approximately seven minutes

will

be lost. The test

and "Test Disk 2". These disk-

completed and the per-

drive 1,

to ensure

STEP

7: Press RETURN, the following will display:

STEP

8: Enter the appropriate responsetothe question and press RETURN.

The computer disk drive and begin the performance test. The screen displays:

will

calculate the maximum number of tracks for the particular

Page 21

The computer This procedure takes up to three minutes per disk. At the end of the operation

the screen displays:

The computer conducts the remainder of the Performance Test and displays:

~.JF.:

OPEt·~

OF'Et·~

~.J

F.:

ITI CLO::;E L·JP

ITI

CLO~:;E

OPEN

OF'Et·~

PEADItKi

~:;CRATCH

FILES

SCRATCH

FILE::; L·JF.:ITE L·JPITE

~.JF.:

L·JPITE PEAD PEAD F.:EAD READ

~.JP

~4Ci

DATA

~'JF.:

~~Ci

DATA

L·JPITE PEAD READ

DATA FILE

~:;CF.:ATCHED

FILE

:::;CPATCHED

Tf;;:ACK

TPACK TF:ACK TF.:ACK

TF.:ACI< TF.:ACK TF.:ACI< TF.:ACK

FILE FILE

will

FILE

DATA

FF:Ot'1

Ot·~

>::::<

::<::<

::<>::

ot·~

::<>::

Ot·~

Ot~

O~~

first format the diskette in drive 0 then the diskette in drive 1.

ot·~

Ot·~

ot·~

Ot·~

1 0

Ot~

Ot·~

O~~

0 1

O!:::

OK.

01.00

01.~X1

~:1

OK OK

01<

00.00

00.

(10

00.00 OCI.OO

00.00

O~].

0(1.00

~X1

0(1.

{:m.O(1

0(1.00

(H].

(H)

O~:1.

00.

~)O

O~).

~]O

00.

(10

00.00

UNIT

PULL TURNING

F.:ERD'T'

HAS

PASSED

DISKETTES

POWEP

•

FROM

OFF.

PEPFORMANCE

DF.:IVES

TEST!

BEFOF.:E

•

STEP

9: Remove the diskettes and return them to their protective jackets. The floppy has

passed the Performance Test.

STEP

10:

any problems have been encountered during this phase of the test, return to

Step 1 and repeat the entire procedure. a satisfactory conclusion to the Performance Test, contact your Commodore dealer.

problems persist and you do not reach

Page 22

THE 2040 AND 3040 PERFORMANCE TEST

When

you have successfully completed the Power-On test, proceed with the Performance

don't

Test. Don't worry if you this point, enter the commands just EXPECTED results are obtained during any step of the test, stop and start over again. The

most likely cause of a problem until you become familiar with the procedure.

All

commands entered

RETURN key. NOTE: Enter the commands exactly

th&

example.Ifthe error indicator lights, you may be abletocontinue the example anyway. Re-enter your last command. may continue.

via

fully understand exactly whatishappening in this test. At

get a feel for what you can do with your disk.IfUN·

an improperly entered command. Thisisto

the keyboard mustbefollowed b a carriage return: press the

shown.

the light goes out, your c.orrection

NOT insert any spaces unless shown in

was

be expected

successful and you

STEP 1: Insert the

diskette into drive 1. Close both drive doors.

STEP 2: Type: OPEN 1,8,15

This command opens logical file 1 on device 8. The secondary address of 15 opens the command channel READY.

NOTE FOR BUSINESS KEYBOARD USERS ONLY: To set the computer for upper case character entry type:

Although it cating with the disk drive, it does permit easy entry. In addition, the examples in this manual can be duplicated exactly. (POKE 59468,14 will return the user lower case letters.)

STEP 3: Type: PRINT#1,"IO"

This command initializes drive head of the drive sary each time the diskette displays your entry, then the word READY.

DEMO

POKE 59468,12 and press RETURN

diskette into drive 0aspreviously instructed. Insert a blank

not absolutely necessarytogive

the device. The screen displays your entry followed by

this command priortocommuni-

The initialization procedure places the magnetic

the proper position above the diskette. This processisneces-

removed and inserted into the drive. The computer

STEP 4: Type: LOAD"*",8 and press RETURN.

The screen displays:

Page 23

STEP 5: Type: RUN.

This causes the sary for the disk unit

brief introductory discussion

Chapter 3 operations. A detailed description of

STEP

6: Type: >D1=O

applies sented in Chapter 7.

This commands the disk drive

DOS

support programtobe executed. (This programisnot

operate, it just simplifies the direct mode commands.) A

DOS

Supportispresented in Chapter 3asit

DOS

make a backup copyofthe

DEMO

neces-

Supportispre-

diskette.

Remove the original envelope. Insert the backup disk into drive

STEP 7: Type: >10

This command initializes the backup diskette.

STEP 8: Type: LOAD"O:DIAGNOSTIC BOOT",8

This command loads the Diagnostic Boot program from the diskette in drive 0

into memory. The screen displays your entry and:

':,ERPCHItJC, LORIIItlCi PERII'T'

FOP

•

DEMO

IiIRC,tJO':,TIC

disk from drive 0 and return ittoits protective

BOOT

•

Concurrent with the display, the drive 0 indicator lights and the drive 0 motor runs.

9: REMOVE THE

STEP

STEP.

STEP 10: Type: RUN and press RETURN

BACKUP

DISKE'ITE BEFORE PROCEEDING

THE NEXT

Follow the directions on the screen.

the test on the screen can be used tion, reset the disk drive by turning the computer's power switch OFF, then

STEP 11: Simultaneously press SHIFT and CLR/HOMEtoclear the screen.

command described earlier

STEP 12: RETURN THE BACKUP DISKE'ITE TO DRIVE 0 STEP 13: Type: >10

This command initializes the diskette in drive

passed.Ifall indicators remain lit in a steady pattern, the directions

find the problem area.

set the computer for upper case character entry.

all

three indicators flicker continuously,

Mter

30 secondsofopera-

ON.

Use

the POKE

Page 24

STEP 14: Type: /O:PET DISK

This loads the PET DISK program from the diskette in drive 0 into memory.

The screen displays your entry and:

':,EAF'CHUK,

LOAD

IHC,

F'EAD'T'

•

FOP(1F'ET

1':,[

•

STEP 15: Type: RUN

The PET DISK program

the drive 0 motor running intermittently

STEP 16: Press the RUN/STOP key.

Simultaneously press SHIFT and CLR/HOME. This completes the 2040 and

3040 performance test.

displayed until terminated. Note that you can hear

each program loads the next.

NOTES

Page 25

Chapter

LEARNING

YOUR

Your

CBM

Floppy

and file handling capability and is controlled directly with:

• BASIC commands entered via

• BASIC statements within programs, and

• special disk commands.

In this chapter

organized in such a way

manner which permits BASIC commands which correspond

Before using

operate

you

your

FLOPPY

Disk Drive adds and enhances

the

will learn howtoapply those commands and statements. This chapter

that

the

functions and format of disk commands are described in a

the

usertoperform disk-related tasks.

each disk maintenance command are also discussed.

floppy disk make sure you know how

Commodore Computer,

HOW

DISK

your

keyboard,

computing power with added storage

to:

DRIVE

For

BASIC 4.0 users, those

USE

elementary programming in BASIC, and

3. open and close files.

the

they

2040,

are used

the

that

per-

exact

the

NOTE: The BASIC statements described in this chapter apply specifically

3040,4040,

ferent format

the

with

usage

This chapter will first acquaint form disk maintenance and file manipulation and will understanding

the

ner, proceedtoadvanced disk programming techniques. Practice examples, and follow

more advanced disk programming techniques will dependtoa large degree upon how well the

fundamentals have been mastered.

and 8050. Certainofthe

produce different results from those described herein when computer or with these commands and statements in

those BASIC commands used for data handling. Approached in this man-

user will then have developed

other

the

step-by-step illustrationsoftheir usage. The understandingofthe

commands and statements may follow a slightly dif-

peripherals. Consult the appropriate manual for

user with those fundamental disk commands

the

other

applications.

then

progressively advance toward an

necessary confidence and programming skills

the

disk commands, read

Page 26

To facilitate your understanding and mastery of Commodore BASIC, two computer terms are stressed in this Chapter: Block Availability Map (BAM) and Disk Operating System

(DOS). Although these are conventional terms, they will be briefly discussed to Commodore Floppy Disk Usage.

they relate

THE BLOCK AVAILABILITY MAP

The

BAMisa disk memory representation of available and allocated space on a disk. When

BAM

the system stores information on a disk, the DOS to determine what space cient spaceisavailabletostore a updatedtoaccount for the space allocated. However, if the DOS detects occupy more space than available, an error message will be generated.

Formatting a disk creates the tion. The

changes occur to the

these changes. Updates

performed on a new RELative or SEQuential data file. Since the 8050 has two blocks available for the updated, this block is written

interchange of information between the two disk, enables the system

BAMisstored on diskette in varying locations depending upon the drive used:

Model

2040,3040,4040

8050

BAM,

only one block of the

available and how many blocks can be allocated.Ifsuffi-

given

file, it will be stored on the disk and the

BAM

whichisthen loaded into DOS memory upon initializa-

BAM

BAMinDOS

the

BAM

maintain a record of free and allocated space on the disk.

memory, the

occur when a programissaved or a CLOSE or DCLOSE

the disk and the other block loaded into memory. This

will be automatically referenced by the

that

a file will

Location and Memory Required

Track 18, Sector 0

128

bytes

Track 38, Sector 0 and 1

2 Blocks

BAMondisk will be updatedtoreflect

BAM

is loaded into memory at a time. When

BAMs,

one in DOS memory and the other on

BAM

(BAM)

BAM

This description of the either the 2040 or 3040. Strict attention from the advantages of developing good programming techniques as well as better understanding of the relationship of one element of the system

The DOSisresponsible for managing information exchange between the disk controller and

the computer.

The DOS performs many functions which are transparent

the operation of the system. For example, the DOS monitors the input/output (I/O) of the

disk so that channels are properly assigned and

occur. In addition search the directory andtodelete and copy files.

There checkout in Chapter 2. Review the Performance Test procedure and observe the special symbols of cedures were fully explained

another function of DOS called

DOS

Support which were used to duplicate and initialize the disks before these pro-

monitoring of disk

can only stress the importance of initialization when using

this basic rule will enable the usertobenefit

develop a

another.

THE DISK OPERATING SYSTEM

the user but which are vital

that

no lengthy waits for an open channel

110,

the DOS also uses the channel structure

DOS

Support which was used during hardware

the

user. Because of its ease of use, DOS Support symbols

(DOS)

Page 27

were easiertoimplement at cedures they replace. and simplify your knowledge

is now appropriatetobriefly discuss how DOS Support can enhance

that

point than attemptingtoexplain

operating your Commodore computer.

the

programming pro-

The first file on

Wedge

puter memory, permits

For example, disk commands which would normally be transmitted PRINT#1fn "commandstring" format may be transmitted via DOS SUPPORT by preceding

the command

cause DOS SUPPORT

with DOS Support special symbols can simplify learning about your Commodore computer

by providing a faster method instructions concerning

program, often referredtoas DOS SUPPORT. This program, when loaded into com-

the

TEST/DEMO diskette

the

usertoenter abbreviations for many disk commands.

with>

or@.Typing slash (I) followed by a program name and RETURN will

load

the

useofthese special symbols and their limitations.

that

comes with your disk driveisthe

the disk using the

that

program into memory. Replacing certain disk commands

communicate with the disk. Chapter 7 contains detailed

Universal

DISK MAINTENANCE COMMANDS

The following disk commands permit the user to perform file manipulation and disk maintenance.

4.0

COMMAND

Diskette Level

BASIC

COMMAND NEW INITIALIZE Prepare diskette for use LOAD"$O" VALIDATE Reconstruct Block Availability

Formats a disk

Read disk directory

Map

FUNCTION

(BAM)

BASIC

DIRECT

HEADER

DIRECTORY

COLLECT

DUPLICATE

COPY Copies files (optional

File Level RENAME Renames a file

SCRATCH Erases a file

NOTE: Diskette commands can be transmitted through that a file has been opened with OPEN ERROR appears upon typing the OPEN command, it means opened but had file.

the

abbreviated commands of

not

been properly closed. This error condition will automatically close the

recover, retype the OPEN command.

Duplicates a diskette

concatenation)

the

disk by PRINT# commands

DOS

support. The examples in this chapter assume

the

OPEN 15,8,15 command.Ifthe

BACKUP

COpy

CONCAT RENAME

SCRATCH

error message ?FILE

that

the

logical file was

Page 28

NEW

Each time a disketteisplaced in oneofthe drives, both the diskette and the drive must be prepared for use. A previously unused diskette must first be formatted in the soft-sector format recognized by your particular disk drive. This may be accomplished by use NEW

disk command.

the

To use the command:

where 15 channel (primary address 8, secondary address 15).

The format of

Where dr=the drive number, 0 or 1

The

NEW user wishes ID, and track and sector numbers at the beginning of each block. The directory header and the

BAM

used on an already formatted diskette (with no ID specified)

reinitialize the ting without an ID

NEW

command, to format the diskette and initialize the disk drive, enter the

PRINT#15,"commandstring"

the logical file number of a file which has been openedtothe disk command

NEW

is:

"NEWdr:fn,xx"

"Ndr:fn,xx"

fn=the file name you wish to assign

characters long.

xx=a unique two-character, alphanumeric identifier supplied by the user.

command (with ID specified)isused on an unformatted diskette or one which the

reformat.

are created and the disketteismade readytoaccept data. The command may be

BAM,

NEW

creates the block headers, writing the sync characters, disk

deallocating all blocks on the diskette. The time involved in reformat-

much less than formatting with an ID.

the disk.Itmay be upto16

clear the disk directory and

Example 1: OPEN15,8,15

PRINT#15,"NO:TESTDISK,88"

These commands will open the command and error channeltothe disk drive and format a disk in drive 0, giving it a disk identifer of 88.

Here's an example of reformatting a diskette using the Example 2:

The diskette will be assigned the name "NEWNAME" and the directory and cleared. This procedure will work only if the diskette has been formatted.

NEW

The The latter will delete the program currently in memory and clear all variables before entering a new program.

OPEN1,8,15 PRINT#l,

disk command SHOULD NOT be confused with the

"NO:

NEWN

AME"

NEW

command and no disk ID.

NEW

command in BASIC.

BAM

will be

Page 29

HEADER (BASIC 4.0 Direct Command)

The HEADER command has the same effectasNEW computers using BASIC 4.0. Since formatting destroys all data previously stored, the

HEADER command has a built-in safety feature that queries the user: ARE positive response to this question permits formatting to take place while a negative response aborts the operation.

The format of HEADER command

HEADER

Where: fn=file name supplied by user but limited to 16 characters.

"fn"

,Ddr,Ixx

dr=drive number, 0 or 1 xx=a unique two character alphanumeric identifier (ID) supplied by user.

(same parameters

used by

is:

NEW

command)

command butisreserved for those

YOU

SURE? A

Initialization (2040 and 3040)

Whenever a disketteisinserted into either drive, for any reason, it ensure that the information on the the diskette currently in the drive. Failure inserted or reinserted into the drive will resultina DISKIDMISMATCH loss of data.

BAM

(in the disk memory)isthe proper information for

properly initialize a diskette each timeitis

MUST

be initialized to

ERROR and/or

Insert the diskette into drive 1 and initialize

OPEN 1,8,15 PRINT#l,"Il"

NOTE: FILE OPEN ERROR could occur if a previously opened file

second OPEN command. If the file

file. If this error

The diskette in drive 1 Remember destroy previously stored data.

The INITIALIZE command on the 2040 and 3040 aligns the read/write head with track 1 on the specified diskette. It then moves this information into the Disk Operating System (DOS) memory.

Since the 2040 and 3040 initialization function depends upon a change of change of diskette, inserting a diskette with an ID identical to a loss of data. This happens because the computer will reference the the previous diskette. Since the IDs are identical the of diskette. A SAVE or DSAVE command may now cause new data data already present on the disk because the area, instead of the current one. The results are unpredictable, and the diskette may become totally useless. For this reason, unique disk IDs must be used whenever possible for each

diskette.

that

displayed, retype the OPEN command and proceed.

now initialized.

formattingisusually a one-time operation and that re-formatting a disk will

still open, the second OPEN command would close the

follows:

was

addressed with a

not confuse formatting and initialization.

track 18, reads the disk label and ID, and loads

to detect a

one previously used may lead

BAM

left over from

DOS

assumes there has been no change

be written over good

DOS

will use the old map of available storage

Page 30

Initialization (4040)

The 4040 utilizes a initialization the new disk. Operator initializationisnot

DOS

2 software routine each time the diskisaddressedtodetermine if

required. If a different IDisdetected, the 4040 will automatically initialize

required if unique IDs are assigned each diskette.

Initialization (8050)

The 8050 utilizes a hardware feature to detect the removal or insertion of a diskette, so it not necessarytoinitialize since thisisan automatic function.

THE DIRECTORY

Confirm the following methods information:

There are two methods available to all users for listing the directory. The first method illustrates the listing procedure using LOAD and the second, the listing procedure in BASIC 4.0 using the DIRECTORY command. If using a 2040 or 3040, and have removed the disks from the drives for any reason, the disks must be INITIALIZED before attempting play and continue.

that

the newly formatted disk has the correct ID and disk name by using one of

list the directory. The directory display includes the following

• Disk name

• Disk ID

•

DOS

version number

• File name

• File type

• Number of blocks used

• Pointer

• Number of available (free) blocks

the

directory. If using a 4040 or 8050, initializationisnot required-insert the diskette

first blockoffile

dis-

LOADS

This procedure will destroy any program currently in computer memory when the directory

LOADed. (Refertothe description of the

a non-destructive directory display procedure.)

STEP 1: Place a formatted disk in drive

ette and continue.

STEP 2: Type: LOAD"$1",8

The screen displays:

LOADI$l".':::

':,EAPCHIHC,

LOAIiItH:' .

PEAD'T'

•

FOJ::'

then press RETURN.

DOS

Support command in Chapter 7 which

1. If using a 2040 or 3040, INITIALIZE the disk-

•

STEP 3: Type: LIST

The directory for drive 1

will display the directory for drive

will

be displayed. SUbstituting $0 for $1 in the format

Page 31

DIRECTORY (BASIC

This command will display the directory without disturbing the content of the memory.

You may type: DIRECTORY is

illustrated which uses the first two unshifted characters followed by a shifted R.

using the full word spelling but the preferred short format

4.0

Direct Command)

To display the directory, type:

using upper case display, type: DI_DO and press RETURN.

The _ in this example represents the upper display the directory for drive both drives if there reference manual for a complete description of this BASIC command.

a formatted diskette present in each drive.

diRdO

1. Typing

and press RETURN.

case

display for a shifted R. Typing DI _

_ or DIRECTORY will display the directory for

See

your BASIC 4.0

Printing The Directory

Quite often, it becomes convenient to affix a diskette directory listing directly on the protective jacket. This permits the user insert the diskette into the drivetoobtain this information. Should you desiretoprint the directory, place the diskette

LOAD

OPEN 4,4:CMD4

LIST PRINT#4:CLOSE4

"$0",8

scan the printed directory listing without having

drive 0 and enter the following commands:

Loads the directory. Opens device 4 (printer) and changes

the primary output device Prints the directory. Returns output

the screen and closes the file.

will

VALIDATE

The VALIDATE command traces through each block of data contain'ed in

diskette. to the diskette. Any blocks which have been allocated but are not associated with a file name, files created using the BASIC 4.0 DOPEN command.

additiontoreconstructing the were never properly closed. operation aborts and leaves the diskette in its previous state. If a VALIDATE error does occur, you must re-initialize before proceeding.

The format of VALIDATE

Where: dr=drive number (0 or 1)

this traceissuccessful, a new

in the case of direct access files

BAM,

a READ errorisencountered during a VALIDATE, the

is:

PRINT#15,"VALIDATEdr"

BAMisgenerated in the disk memory and written

willbefreed for use. This will not affect relative

VALIDATE deletes files from the directory that

all

files on the

Page 32

NOTE: You may abbreviate VALIDATEtoV.1f a drive numberisnot

ette in the last drive used during the current session

Example: OPEN1,8,15

PRINT#l,"VO" or

verified.

specified, the disk-

PRINT#l,"VALIDATE

The COLLECT command in BASIC 4.0 performs the same functionasVALIDATE. Either command will accomplish the following:

• Recreate a Block Availability

• Delete files from the directory which were never properly closed. (OPENed but never CLOSEed)

The format of COLLECT is:

COLLECTDx

Where: x=drive number

Example 1: COLLECT

Verifies drive 1

Example 2:

COLLECT Verifies drive 0

(drive defaults

(lor

COLLECT (BASIC

Map

accordingtovalid data on disk

4.0

Direct Command)

DUPLICATE

The DUPLICATE command formats the destination diskette and transfers each block of information from the source diskette cate of the source diskette. a diskette.

Due to the various formatting protocols used by mand may NOT be used interchangeably when using diskettes prepared on different disk drives.

Use

the following guidetoavoid confusion:

DUPLICATE command may be used

• a 2040 or 3040 using diskettes formatted on a 2040 or 3040.

• a 4040 using diskettes formatted on a 4040.

DUPLICATE command may NOT be used

• a 2040 or 3040 using diskettes formatted on a 4040.

• a 4040 using diskettes formatted on a 2040 or 3040. To reproduce a diskette under these conditions, use the

gram found on the TEST/DEMO diskette which came with your disk drive.

Use

the destination diskette, thus creating an exact dupli-

this procedure for one method of creating a backup copy of

DOS

1, DOS 2, and

on-

DOS

COpy

2.5, this com-

ALL DISK pro-

Page 33

The formatofDUPLICATE is:

PRINT#lfn,

Where: ddr=is the destination diskette (either 0 or 1)

not

reverse the order of the drive numbers. If you do, you will lose all data and there

no waytorecover it. Observe good practice and place a write protect tab on the diskette containing the valuable information. This procedure will prevent overlaying good information.

Example: OPEN1,8,15

NOTE: The letter Disa legal abbreviation for DUPLICATE command.

The BACKUP command in BASIC 4.0 performs the same functionasDUPLICATE. The format of BACKUP is:

"DUPLICATEddr=sdr"

sdr=is the source diskette (either 0 or 1)

PRINT#l,"DUPLICATEO=l" or PRINT#l,"DO=l"

BACKUP (BASIC

4.0

Direct

Command)

BACKUP Dsdr TO Dddr.

Where: ddr=is the destination drive

sdr=is the source drive

Note

that

the format of BACKUP differs from DUPLICATE in that the order of the drives

reversed.

Example: BACKUP

This has exactly the same effect as the previous example given when discussing DUPLICATE

command. For a complete explanation of the BACKUP command, refer

BASIC 4.0 Reference Manual.

(either 0 or 1)

(either 0 or

the Commodore

COpy

The

COpy tiple copies (under different names) used catenated into the destination file.

copied

with a

command allows youtocopy files from one diskettetoanother,tocreate mul·

files on the same diskette. This command can also be

concatenate data files on the 4040 or 8050.Upto four source files can be con-

the 4040 or 8050 all files from one drive may be

a formatted diskette in the other drive. The COPY command may be abbreviated

COpy

To copy a single file: PRINT#1fn,

disk command can be formatted three ways depending upon application:

"COpy

ddr:dfn=sdr:sfn"

Page 34

PRINT#1fn,"Cddr:dfn=sdr:sfn"

To concatenate and copy: PRINT#1fn,"COPYddr:dfn=sdr:sfn,sdr:sfn

PRINT#1fn,"Cddr:dfn=sdr:sfn,sdr:sfn

To copy all files on a diskette:

Where: ddr=is the destination drive. The file

drive. This may be the same or different from the source drive.

dfn=is the destination file name. This name may be either a new name or the

same as the old file name unless the ddr

are

In example 1, a fileiscopied from the diskette in drive 1tothe diskette in driveO.In example 2, files from both drives are concatenated into a file on drive files from drive 0 are copied to drive the disk unit if a file example).

exist on the same diskette, they must have different names.

PRINT#1fn,

PRINT#1fn,"Cddr=sdr"

be copied already exists on the destination drive (drive 1 in this

"COpy

error message FILE EXISTS will be generated in

ddr=sdr"

istobe copied

the same as the sdr.Ifboth files

onto

...

the diskette in this

1. In example 3, all

Example

A file

Example 2: PRINT#I,"Cl:JDATA=I:ACCTl,O:ADATA,O:BDATA"

Files from both drives are concatenated into a file on drive be short,asthe maximum length of a disk command stringis40 characters.

Example 3:

All

Example 3 illustrates one waytoupgrade from a 2040 or 3040 formatted diskettetoa 4040 format: place a formatted diskette in drive copy all files from

PRINT#I,

copied from the diskette in drive 1todrive

PRINT#I,

files from drive 0 are copiedtodrive 1.

0 onto

"Cl

:ACCTI=0:ACCT"

"Cl

=0"

1 and the diskette

1. Note

that

file names should

be upgraded in drive 0 and

Page 35

COPY (BASIC 4.0 Direct Command)

The

COpy

mand and its formatisalso dependent upon application. Use

this formattocopy the contents of the entire disk:

direct command in BASIC 4.0 performs the same functionasCOPY disk com-

COpy

Use

this formattocopy a single file:

COpy

Where: sdr=the source diskette

Dsdr TO Dddr

Dsdr,"sfn" to Dddr,"dfn"

ddr=destination diskette

fn=file name

CONCAT (BASIC 4.0 Direct Command)

The CONCAT direct command in BASIC 4.0 permits the usertoconcatenate files. The format of CONCAT

CONCAT Dsdr,"sfn" TO Dddr,"dfn"

where the file named dfn on drive ddr the concatenation. For example:

CONCAT DO,"YOURFILE" TO D1,"MYFILE"

will

contain the contents of both dfn and sfn after

will

result in MYFILE on drive 1 containing the data from the old MYFILE and from

YOURFILE. YOURFILE will remain unchanged.

NOTE: The concatenation feature of COPY disk command and CONCAT direct command are valid only for

For further information regarding use of BASIC COPY and CONCAT commands, refer the Commodore BASIC 4.0 Reference Manual.

DOS

2. to

RENAME

The RENAME command renames an existing file. A file can not already exist with the file name specified in the command or the FILE EXISTS error message will be generated.

The format of RENAME is:

PRINT#1fn, "RENAMEdr:nfn=ofn"

Where: dr=the disk drive on which the diskette

nfn=the new name of the file.

located.

Page 36

ofn=the old name of the file.

lfn=a logical file number. You assign this number arbitrarily and it may be any

whole number between 1 and 255.

NOTE: The letter R

The RENAME direct command in BASIC 4.0 performs the same functionasRENAME disk command.

The format is:

RENAME Ddr,"ofn"

NOTE: Close any open files before using the RENAME command since the disk will

execute this command on any active files. For further information on the RENAME command, please refer

4.0 Reference Manual.

a legal abbreviation for RENAME.

RENAME (BASIC

"nfn"

4.0

Direct Command)

the Commodore BASIC

not

SCRATCH

The SCRATCH command erases unwanted files from the specified diskette and itsdirectory.

You can erase one file, several files, or all the files on a diskette.

The format of SCRATCH is:

PRINT#lfn,"Sdr:fn,dr:fn

Where: dr

To erase one file, enter the entire name of the file:

Example: PRINT#l,"SO:ACCT" To erase several files with unrelated names, enter the entire name of each file Example: PRINT#l,"SO:ACCT,O:CUSTOMER,O:INV"

To erase several files at one time where names have something in common, refer in

APPENDIX B concerning pattern matching. You may erase all files on a diskette using pattern matching Example:

the disk drivetobe searched.

alone means "last drive accessed", with dr refers to the specified drive, where not used means

the name of the filetobe

PRINT#l

"~O:*"

...

"both

dr :fn"

drives".

erased.

in the following example:

be deleted:

the rules

Page 37

SCRATCH (BASIC 4.0 Direct Command)

SCRATCH direct command in BASIC 4.0 performs the same functionasSCRATCH disk

command.

The format is: SCRATCH

Where: dr=drive number

fn=filename

Pattern matching rules may be used with this command.

there permits the file

For a complete description of the SCRATCH direct command, please refer to your BASIC

4.0 reference manual.

a built-in safety feature

be SCRATCHed while a negative response aborts the operation.

Ddr,"fn"

filetobe scratched

that

queries the user: ARE

with the HEADER command,

YOU

SURE? A positive response

NOTES

Page 38

Chapter

BASIC COMMANDS

FOR DATA HANDLING

BASIC

The BASIC commands described in this chapter, allow the usertocommunicate with and transfer data to and from the disk drive.

These commands are available for ALL versions of Commodore BASIC:

OPENlfn,8,sa,

CLOSElfn

LOAD"dr:fn",8

SAVE"dr

These commands are available ONLY in BASIC 4.0:

DOPEN#lfn,"fn" DCLOSE#lfn DLOAD"fn"

Where: lfn=logical file number (any number between 1 and 255)

COMMANDS

"dr

:fn,t,r/w"

:fn",8

fn=file name supplied by user

x=dr=disk drive number

8=device number (8 for disk, 2 for second cassette, 4 for printer)

sa=secondary address

U=logical file

ASSOCIATED WITH FLOPPY DISK DRIVES

VERIFY"dr:fn",8 PRINT#lf

GET#lfn

INPUT#

VE"fn"

DSA RECORD#lfn,R,B

(lor

0): both Dx and dr defaultto0

All upper-case characters shown in format are essential for the proper execution of a com-

via

mand and must be typed by user. These commands are entered shifted characters only. On the

BASIC 3.0 commands are upward compatible with BASIC 4.0 commands. Each command will be defined along with a brief example

floppy disk you

try the examples and procedures.

attachedtoyour computer and has passed the performance test,weencourage

CBM

Business Model they will appear in lower case.

illustrate their use. As soon as your dual drive

the keyboard using un-

Page 39

SAVE and DSAVE (Writing a Program to a Diskette)

a programisin computer memory, it can be movedtoa diskette for storage. This is

accomplished with the SAVE (any Commodore BASIC) or DSAVE (BASIC 4.0) commands. Any data transferred with the SAVE

the DOS as a program (PRG) file. Both commands transfer PRG files from the computer's

memory and the device number. The device number will default it

not specified.

The format

SAVE"dr:fn",dn

Where: dr=is the disk drive number.

This following example illustrates creating a one line program, SAVEing it on the diskette in drive 0 under

Example: 10?"THIS IS A TEST"

The DSAVE command performs modore disk system and BASIC 4.0.

the specified diskette. You must specify the drive number, the program name,

ofSAVE

fn=is any file nameof16

dn=is the device number and it must be 8.

the

SAVE"O:TESTPROG",8

VERIFY"0:TESTPROG",8

is:

transferred

name TESTPROG, and VERIFYing that itisresident on disk.

the

DSAVE commands are automaticaly designated by

device 1 whichisthe

must be 0 or 1.

characters or less you wishtoassigntothe

diskette. Blanks are countedascharacters.

the

same functionasSAVE, butisvalid only with a Com-

tape unit if

file to be

The format is:

DSAVE"fn"Ddr

"fn"

This command will save a file named "fn",

may be any nameof16 characters or less.

on the floppy disk in drive 0 or 1. The file name,

LOAD and DLOAD (Reading a Program from a Diskette)

A program stored on diskette may be loaded into memory using dore BASIC) or DLOAD (BASIC 4.0) commands.

The LOAD and DLOAD commands transfer PRG files from the specified diskette

computer's memory. You must specify the drive number, the program name, and the device number. The device number will default LOAD is:

LOAD''dr

Where: dr=is the drive number from which you are loading data.

:fn"

,dn

unit 1 whichisthe cassette unit. The format

the

LOAD (any Commo-

must be 0 or 1.

the

Page 40

fn=is the file name previously specified in the SAVE command and/or stored

the disk directory.

dn=is the device number and it must be 8.

The following example illustrates how a program puter memory, then executed. To do this example, first type

key fuse the

Example

The DLOAD command transfers performs the same function designed for a Commodore disk unit using BASIC 4.0. The device number will default to 8 if not specified. The drive number will default

A successful LOAD or DLOAD closes all open files. Therefore you must command in order tocontinue communicating with the disk drive command and error channel.

clear your computer's memorysothat you can see that it really works. Don't con-

NEW

command in BASIC with the

LOAD''0 :TESTPROG",8 READY. RUN

THIS

DLOAD"fn",Ddr

A TEST

loaded from the diskette into the com-

NEW

and depress RETURN

NEW

disk command used to format your disk.

LOAD, butisspecifically

to0is

not specified.

give

a new OPEN

VERIFY

The format of VERIFY command

is:

VERIFY''dr:fn",8

"fn"

This command verifies that a file named

information which VERIFY command used with the tape cassette. Once again, dr refers to the drive number, either zero or one. Note that the format of this command specifies that the drive number placed before the filename. The 8atthe end of this commandisthe device number (8 for disk, 2 for second tape cassette).

STEP 1: Write a short program and save it on a diskette in drive 1 under the name

using the procedure described under the section on SAVE. NOTE: It

between the

STEP

Type: VERIFY "1:TEST",8 Once verified, the screen displays:

stored in the computer's memory. This commandisthe sameasthe

important that the program in memoryisnot changed in any way

save

and verify operations.

stored on a floppy disk contains the same

"test"

Page 41

a verify error occurs, reSAVE the program and verify it again.

VERIFY may also be used in

the

format:

VERIFY'

in ordertoperform verificationofthe last file saved without re-typing the filename. Con-

firm by following these steps: STEP 1: Write a short program and save it. STEP 2: Clear STEP

The VERIFY function will be performed comparing the last file savedtothe content memory.

'*",8

the

screen.

Type: VERIFY

"*",8

OPEN

This command sets up a correspondence between a logical file number and a file which exists on disk. opened.

The format

also reserves the buffer space within the disk unit for operations on the file being

the complete OPEN command is:

OPENlfn,dn,sa,"dr:fn,ft,mode"

Where: lfn=the logical file number

dn=the device number; in this case 8

sa=the secondary address. It may be any number from 2to14 and may be used

either for input or dr=the drive number: 0 or 1 fn=the name of the file.

ft=the file type. It may be SEQ (for sequential), USR (for user), REL (for rela-

tive) or PRO (for program).

mode describes how the channel WRITE

NOTE: Secondary address 15isthe

are discussed in subsequent chapters. Secondary addresses

operating systems (BASIC and DOS) for LOADing and SAVEing programs. Examples:

(W).

OPEN2,8,2,"O:FILE1,SEQ,WRITE" OPEN3,8,9,"1:TESTDATA,PRO,WRITE"

output

as specified in mode. See note below

to be used. It may be either READ (R) or

command and error channel and has special uses which

0 and 1 are reserved by

the

OPEN8,8,8,"O:NUM,USR,READ"

Page 42

The contentsofan existing file (on 4040 and 8050 only) may be replaced by preceding the drive number with an

OPEN3,8,5,"@0:JDATA,USR,WRITE"

the specified file does not exist, then normal OPENing procedures are executed.

sign

(@)

in the OPEN command.

You can also assign some of the OPEN parameters

examples: Example

Example 2:

The preceding methods are convenient when it same file name.

The DOPEN commandisavailable onlytoBASIC 4.0 users. or 8050, DOPEN may be used

The format of DOPEN is:

Where: lfn, fn, and dr are the sameasdefined for OPEN.

FL$="O:FILEA,SEQ,READ" OPEN1,8,14,FL$

FL$="O:FILEA" OPEN1,8,14,FL$+",SEQ,WRITE"

create relative files or sequential files of fixed length.

DOPEN#lfn,"fn",Ddr,Lrl (,ONUdn)

Lrl defines the record length

(,W)

equaltorl

a variable nameasillustrated in these

necessarytoopen several channelstothe

When

used with either a 4040

DOPEN

ONUdn specifies Wmay be specified

files, the file will be opened

PENisnot available for the standard 2040 or 3040.

The CLOSE command closes a file opened by the OPEN command. Its format is:

CLOSE lfn

Where: lfn=the logical file number of a file opened by

Always close a file after working with it. You are files in the computer and five in files

soonaspossible. This way you will always have the maximum numberoffiles avail·

able for use.

the

device number equal to dn (with default device being 8)

mean write mode.IfWisnot specified for sequential

read.

the

OPEN command.

not

allowed to have more than ten open

the

disk drives, so itisprudenttomake a habit of closing

Page 43

lOSE

The DCLOSE commandisavailable only to BASIC 4.0 users. This command closes files

opened with the DOPEN command.

The format of DCLOSE is:

DCLOSE#lfn

Where: lfn=the logical file number of the file to be closed.

The DCLOSE command may also be used in this format:

DCLOSE ONUdn

Where: dn=the device number of the disk unit (defaults

When

used in this form,DCLOSE command closes all active disk files on the specified unit.

The following examples illustrate some applications of

8).

LOSE command:

Example 1:

Example 2:

LOSE Close all files currently OPEN. DCLOSE#5 Close only logical file 5.

CLOSING THE COMMAND CHANNEL

Closing the command channel closes all channels associated with the disk drive. part of the logical file environment that the files have been closed.

The following example illustrates a situation in which several channels are closed down by a single CLOSE command.

Example:

affected. That is, the computer does

The command channel Data Channels

are opened for writing.

not

other

recognize

opened.

A channel mistake. An error message screen.

Since there was an error, all logical files in the computer are closed, disk drive are still open. To close the disk channels, type:

openedtothe printer by

displayed on the

but

the channels in the

Page 44

OPEN1,8,15 CLOSE1

Now all data channels in the disk drive are properly closed.

CLOSING THE DATA CHANNEL

The CLOSE command closes a file and the data or command channel associated with it. Whenever you close a file opened with a write channel, the closing of that file writes the

final block of data with a read channel, that channel

the disk and updates the disk directory.

simply closed down.

When

you close a file opened

NOTE: all when there are any files open since the files

When

a driveisinitialized with INITIALIZE,

channels associated with that drive are deleted. These commands should not be executed

willbedisrupted.

NEW,

DUPLICATE, or VALIDATE,

PRINT #

The PRINT# command transmits a disk command stringtothe drive. The format of PRINT# is:

PRINT#fn,"commandstring" Where: "commandstring"=disk handling or disk file handling commands. These disk commands

PRINT# may also be used A semicolon must be used

3.0 the diskette by the BASIC PRINT# routineaspart of the data terminator.Itis be The line feed use

avoid sending extraneous line feedstothe diskette. These characters are written

aware of this face because the carriage return aloneisseenasa terminator by the DOS.

the following format:

lfn=a file previously opened using secondary address 15

are discussed

to as

then stored in the fileasthe first character in the next record. To avoid this,

detail in Chapter 3 of this manual.

transmit data to a previously-opened sequential or relative file.

a terminator for each PRINT# statement when using BASIC

important to

Example: PRINT#2,"JONESABC";CHR$(13); The CHR$(13)

the disk. BASIC 4.0 users do

from it). In BASIC 4.0, any file opened with lfn less than 128 will automatically suppress the line feed.

The following format may then be used:

PRINT#1fn,A$

This will produce the desired value of A$ for the record, and will not interfere with the next record.

the carriage return necessary for the proper termination of the record on

When

this recordisinput, the result will be JONESABC whichisthe desired result.

not

needtofollow this procedure (though no harmful effects will result

Page 45

Several variables may be writtentothe disk at the same time. The format:

PRINT#lfn,A$,B$,C$

will

result in a single variable (A$+B$+C$) being retrieved by the input command.

The format:

PRINT#lfn,A$CHR$(13)B$CHR$(13)C$

will result in the variables A$, B$, and C$ being separated by carriage returns, and they may then be input as separate variables.

INPUT #

The INPUT# commandisusedtotransfer information from an IEEE device suchasthe disk drive into computer memory. INPUT#isvalid only when used in a program and only when referencing a logical file

The format for INPUT# is:

INPUT#lfn,A$ or INPUT#lfn,A

that

has been OPENed for input.

Where: lfn=a file previously opened using secondary address

A$=a string variable which will contain the data transferred.

A=a

numeric variable which will contain the data transferred.

INPUT# may also be used

INPUT#1fn,A$,B$,C$

Where: A$, B$,

In this format, the data strings must have been separated by carriage returns ( CHR$(13) ) at the time they were written may contain more than

Example 1:

Example 2:

20 INPUT#2,A Input the next data item which must be in numeric form and assign the value

to variable

transfer several stringsofdata at one time:

will contain the data transferred from the disk.

the disk in ordertobe retrieved separately. No single string

characters if itisto

be INPUT.

10 INPUT#8,A$ Input the next data item

a string and assign ittovariable A$.

Page 46

Example 3:

60 INPUT#7,B,C$

Input the next two data items and assign the first the secondtostring variable C$.

For strings longer than 80 characters, the GET# command must be used.

The GET# commandisusedtotransfer individual bytes of information from an IEEE

device such gram

and only when referencing a file that has been OPENed.

The format of GET# is:

GET#lfn,A$

Where: lfn=a file previously opened using secondary address 15

the disk drive into computer memory. GET# is valid only when usedina pro-

A$=a string variable which will contain the data transferred.

numeric variable

Band

GET#

GET# may also be used ing strings which have been written to the disk in a format which INPUT command (strings longer than 80 characters).

For example: 10 AA$=""

20 FOR 30 GET#lfn,A$

40 AA$=AA$+A$

50 NEXT

a program segment which would resultina string of length 254 being transferred from the

disk (logical file number lfn)

transfer several bytes of information, whichisuseful for retriev-

unacceptable for the

1=1

254

the computer memory and stored in the variable AA$.

RECORD#

The RECORD# commandisused priortoa PRINT#, INPUT#, or GET# in order to posi-

tion the file pointer to the desired record (and byte) of a relative file. For example, if record pointer

are generated

RECORD# is available only

is set beyond the last record and PRINT#

expand the filetothe desired record.

users equipped with BASIC 4.0. The format is:

RECORD#lfn,r

used, the appropriate number of records

Where: lfn=a logical file number of a file previously opened with the DOPEN command

r=the desired record number. 4 may be either a variable name or value, how-

ever if r 0<=r<=65535

b=the byte position desired within the record. Byte positioning

1<=b<=254

a variable name, it must appear enclosed in parentheses.

optional.

Page 47

The following example illustrates how RECORD command

Example:

RECORD#1,120 Using the RECORD command

20 INPUT#1,A$

select

the

used with INPUT#:

record.

Input the next data item as a string and assign it

A detailed example of found in Chapter

the

usage of the RECORD command for relative file manipulation

aUICKLOAD

This command featureisvalid with command will also function properly with a retrofitted 2040.)

This command loads the first file on the disk in drive 0 into memory. To ensure that the first program on the diskette given

after a cold start. STEP 1: Turn the computer OFF, then ON. STEP 2: Make sure the disk containing a programasthe first fileisin drive 0 and

drive door

3: Simultaneously press the SHIFT and RUN/STOP keys.

STEP The computer will initialize the disk in drive

and load it.

closed.

DOS

2 and BASIC 4.0, and either a 4040 or 8050. (This

accessed, the command must be the first disk command

0, search for the first program on that disk,

variable A$.

FEATURE (BASIC

that

4.0)

the

When

using this feature the computer will automatically execute the DLOAD and RUN

commands and it

not necessarytoenter either command.

Page 48

MOVING

This example illustrates a session with the computer, a tape cassette and a disk drive. The purpose diskette previously stored on the cassette.

Example:

istocopy a cassette program to a diskette. The programisthen read from the to

the computer's memory and printed.Itis

A TAPE PROGRAM TO DISK

assumed that the

BASIC

program

was

Load the file from the cassette tape computer's memory.

Create a program file containing the program on diskette.

Erase everything from memory. (The commandinBASIC NEW

disk command will format a disk.)

Load the program back into the computer's memory.

Run the program

will clear memory; the

verify it has been loaded.

the

NEW

Page 49

Chapter

ADVANCED

DISK PROGRAMMING

This chapter provides detailed information about The utility commands provide the programmer with low-level functions that may for special applications such

special disk handling routines and random access techniques.

DOS

structure and disk utility commands.

used

COMMODORE DISK OPERATING SYSTEM (DOS)

The DOS file interface controllerisresponsible for managing all information between the disk controller and the

sulting in a faster response The file systemisorganized by channels which are opened with the

ment.

When

executed with the OPEN statement, the channel and allocates either one or two disk I/O buffer areas. If either the workspace or the buffer is not available, a

structure The common memory between the disk controller and the file interface controllerisused

256-byte buffer areas. Three of the sixteen buffers are used by the

Availability

queue.

The job queue side by providing the disk controller with sector header and type of operation information. The disk controller seeks the optimum job and attempts execution.

then returned in place of the job command.Ifthe jobisunsuccessful, the file side re-enters the job a given number of times, depending upon the operation, before generating an error message.

search the directory, and to delete and copy files.

Maps

the vital link between the two controllers. Jobs are initiated on the file

IEEE488

(BAM), variable space, command channel I/O, and disk controller's job

bus. Most disk I/Oisperformed on a pipelined basis, re-

a requested operation.

DOS

assigns a workspacetoeach

CHANNEL errorisgenerated. The

BASIC

DOS

OPEN state-

also uses the channel

for the Block

error condition

The secondary address given in the The number the user assigns

the work areas, and statements transmit secondary addresses of 0 and 1, respectively. The

not relatedtothe

OPEN

a channelisonly a reference number thatisusedtoaccess

statementisused by

DOS

ordering of channels. The LOAD snd SAVE

DOSasthe channel number.

DOS

automatically

Page 50

interprets these secondary addresses as LOAD and SAVE functions. Unless these functions

are desired when opening files, avoid secondary addresses bers,2 data.

through

14,

may be usedassecondary addressestoopen uptofive channels for

0 and1.The remaining num-

DISK UTILITY COMMAND SET

The disk utility command set consists of the following commands:

Commands BLOCK-READ BLOCK-WRITE

BLOCK-EXECUTE BUFFER-POINTER BLOCK-ALLOCATE BLOCK-FREE memory-write memory-read memory-execute

USER

Where: ch=the channel number in DOS: identicaltothe secondary address in the

associated OPEN statement.

Abbreviations

B-R B-W B-E B-P B-A

B-F M-W M-R M-E

General Format "B-R:"ch,dr ,t,s "B-W:

"ch,dr,t,s "B-E:"ch,dr,t,s "B-P:"ch,p "B-A:

"dr

,t,s "B-F:"dr,t,s "M-W"adl/adh/nc/data "M-R"adlladh

"M-E"adlladh "Ui:parms"

dr=the drive number: 0 or 1

the

t=the track number: 0 thru 77. For each track number,

for the 2040, 3040, 4040, and 8050 are shown in Appendix

p=the pointerposition for the buffer pointer.

adl=the low

adh=the high

nc=the number

data=the actual data in hexidecimaI. This is transmitted by using the CHR$

function, i.e. CHR$(1) would send 01, (decimal 1).

i=the index

parms=the parameters associated with the U command (optional).

byteofthe address*.

byte

of the address*.

characters: 1 through 34*.

the

User

Table.

the

binary equivalentofhexidecimal

sector ranges

Page 51

The values used in conjunction with the memory commands exist in the 2040, 3040, and

4040 as hexidecimal values and must be transmitted equivalent of the desired hexidecimal value.

NOTE:

If using variables the format must have only the command in quotes.

CHR$(n), where nisthe decimal

For

example:

"B-R:"ch,dr,t,s

"B-R:ch,dr,t,s"

To avoid confusion, it

implied in the preceding format, these commands may be abbreviatedtothe first characterofeach of the key words. Abbreviations only are accepted for those commands shown in lower case. The parameters associated with each command are searched for starting at a colon (:), or in the fourth character position if a colon ing shows four ways

NOTE: If using a 4040 initialize the disk before the buffer read or write.

Examples:

Parameters following the key words within quotation marks may be separated by any combination of the following characters:

"BLOCK-READ: "2,1,4,0 "B-R"2,1,4,0

"B-R"2;1;4;0 "B-READ:"2;1;4;0

good practicetouse this format when using variables or constants.

that

the same block-read command may be given.

Character Name

correct incorrect

not present. The example follow-

Keyboard Representation Skip Space Comma

The use of these characters permits sending both ASCII strings and integers.

Parameters not within the confines of quotation marks should be separated by semicolons (;).

the following discussions, a PRINT# is assumed in all examples.

<cursor right> Space bar

BLOCK-READ

This diskette utility command provides direct accesstoany block on a diskette in either disk drive. Used in conjunction with other block commands, a random access file system may be created through BASIC. This command finds the character pointer in the O-position of the block.

or-Identify (EOI) the computer.

When

a character in this positionisaccessed with GET# or INPUT#, an End-

sent. This terminates an INPUT# and sets the Status

Word

(ST)to64 in

Page 52

The format "B-R:"ch;dr;t;sisillustrated in the following example. Example: "B-R: "5;1;18;0

Reads the block from drive 1, track 18, sector 0 into channel 5 buffer area.

Mter

using BLOCK READ to transfer the data to the buffer, the data may be transferred memory by INPUT# or GET# from the logical file openedtothat that secondary address).

The

command described under USERissimilar to the BLOCK-READ command.

disk channel (Le., using

BLOCK-WRITE

When

this commandisinitiated, the current buffer pointerisusedasthe last character

pointer and

indicated block on the diskette and the buffer pointer

placed in the 0 position of the new buffer. The bufferisthen written to the

left in position 1.

The format Example:

BLOCK-WRITE retrofits. The BLOCK-WRITE command

"B-W:

Writes channel 7 buffer to the block on drive 0, track 35, sector 10:

"ch;dr;t;sisillustrated in the following example.

"7;0;35;10

not available with

DOS

2. This includes the 4040 and all 2040/3040

is replaced by the

command for the 4040.

BLOCK-EXECUTE

This command allows part of the loaded into disk drive memory and executed. Interface Controller begins execution of the contents after the block

Execution must be terminated with a return from the subroutine (RTS) instruction. Future

system extensions or user-created functions may implement this command.

The format "B-E:"ch;dr;t;s Example: "B-E:"6;1;1;10

Reads a block from drive 1, track 1, sector cutes its contents beginning at position 0 in the buffer:

DOS

or user designed routines to reside on disk and be

B-Eisreally a

illustrated in the following example.

B-R

into channel 6 buffer and exe-

with an addition. The File

read into a buffer.

BUFFER-POINTER

This command changes the pointer assocIated with the given channel to a new value. This useful when accessing particular fields of a record in a block or, if the blockisdivided into records, individual records may be set for transmitting or receiving data.

The format "B-P: "ch,p Example: "B-P:"2;1

Sets channel 2 pointer buffer:

illustrated in the following example.

the beginning of the data area in the direct access

Page 53

BLOCK-ALLOCATE

The appropriate allocated (used). In future operations, the programs or writing sequential files. The updated closure of a write file or the closure of a direct access channel.

BAMisupdated in the

DOS

memorytoreflect the indicated block

DOS

skips over the allocated block when saving

BAMiswrittentodiskette upon the

If the block requested has been previously allocated, the error channel indicates the next

available block (increasing track and sector numbers) with a no blocks available that are greater in number than the one requested, zeroes are displayed as

track and sector parameters.

The format "B-A:"dr;t;s

Example: "B-A: "1;10;0

Requests that block (sector) 0 of track 10 in drive

NOTE: The error channel should alwaysbecheck when using BLOCK ALLOCATE,sothat

if the block message will also indicate the next available block.

Example: INPUT#15,EN,EM$,ET,ES

already allocated, it will notbeoverwritten. If the blockisallocated, the error

Reads the next track and sector, respectively, into ET and ES, assuming that

lfn=15 has been previously OPENed to the disk error channel.

illustrated in the following example.

BLOCK error. If there are

flaggedasallocated on the diskette

All

three

MEMORY language programs. BASIC statements may MEMORY M-E:

commands by using the CHR$ function. The system accepts only

neither verbose spelling or the use of the colon (:)ispermitted.

commands are byte-orientedsothat the user may utilize machine

used to access information through the

Memory-Write

This command provides direct accesstothe loaded to the disk drive through this command and then executed using the EXECUTE command or one of the USER (U) commands. with each use of the command. The low byte of the address must precede the address.

The format Example:

"M-W:

Writes four bytes

"adl/adh/nc/dataisillustrated in the following example.

"CHR$(00)CHR$(18)CHR$(4)CHR$(32)CHR$(0)CHR$(17)CHR$(96)

buffer 2 ($1200 or decimal 4608):

DOS

memory. Special routines may be down-

Upto34 bytes may be deposited

MEMORY

M-R,

MEMORY-

the

high byte of

M-W,

and

Page 54

Memory-Read

The byte pointed to by the addressinthe command string may be accessed with this com-

DOS

mand. Variables from the

M-R

command. The

transmitting information (secondary address 15) transmits the byte. error channel after a MEMORY-READ command until a the MEMORY commands

The format "M-R: "adlladh Example: "M-R"CHR$(128);CHR$(O)

Accesses the byte located at ($0080 or decimal 128):

command changes the contents of the error channel since itisused for

or the contents of the buffers may alsoberead with this

the computer. The next GET# from the error channel

An INPUT# should not

executed.

illustrated in the following example.

DOS

executed from the

command other than one of

Memory-Execute

Subroutines in the

DOS, terminate the subroutine with RTS ($60). The format "M-E: "adlladh Example: "M-E"CHR$(128);CHR$(49)

Requests the execution of code beginning at $3180.

DOS

memory maybeexecuted with this command. To returntothe

illustrated in the following example.

USER

This command provides a link to 6502 machine code accordingtoa jump table pointed by the special VSER pointer. Refer to Table5.The second character in this command

usedasan index to the table. The ASCII character 0 through 9 or A through 0 maybeused. Zero sets the VSER pointer to a standard jump table that contains links

The special VSER commands BLOCK-READ and the BLOCK-WRITE commands.

The format of

"VI:

forces the character count (buffer pointer)to255 and reads an entire block into

memory. This allows complete access to

is:

"ch;dr;t;s

(or VA) and V2 (or VB) can be usedtoreplace the

all

bytes in the block.

special routines.

The format of

"V2

V2 writes a buffer

B-W

does. Thisisuseful when a blockisto be read in (with B-R) and updated

field and PRINT#), then written back to diskette with

Refertothe random access exampleinChapter 6 for an application of the

commands.

V2 is:

:"ch;dr;t;s

a block on the disk without changing the contents of position 0

V2.

(B-Ptothe

and V2

Page 55

USER

DESIGNATION

Table 5. Standard Jump Table

ALTERNATE

USER

DESIGNATION

FUNCTION Ul U2

U3 U4 U5 U6

U7 U8 U9 U:

thru

U9 commands are user-defined. The locations jumpedtoare located in the buffer

areas

RAM and routines may be written to reside there and downloaded using the

command. Locations D008,

the

in that

2040/3040 and USER commands may be used

position. Location

IOFOisthe

UA UB

UC UD UE UF UG UH

DOOB,

BLOCK-READ replacement BLOCK-WRITE replacement

jump jump jump to jump jump jump jump

DOOE,

and

DOD5

location of the

2040/3040 4040 8050 to to

$1300 $1300 $1300

$1303 $1303 $1303

$1306 $1306 $1306 to to to to

$D008 $DOOB $DOOE $DOD5

$1309 $1309 $130C $130F $130F

$10FO $10FO

power up vector

are located in the expansion ROM slot

access a ROM or EPROM located in

NMI

vector in the 4040 and 8050.

$130C

M-W

Page 56

Table 6. Block DistributionByTrack

2040,3040

Track number

1to17

18to24

25 31to35

4040

Track number Sector Range

1to17 18to24 25to30 31to35

8050

Track number

1to39 40

53 o

54to64 65

77 o

Any block on a diskette may be examined by using

on the TEST/DEMO diskette.

Block or

Sector Range

o o o o

Block

oto o o o

Block or

Sector Range Total

o o

to to to to

to to to

to to to to

Total

20 19 17 16

20 18 17 16

28 26 24 22

the

program DISPLAY T&S, provided

21 20 18 17

Total

21 19 18 17

29 27 25 23

Tables 7 through 12

PLAY T&S program.

will

assist the user in interpreting information obtained using

the

DIS-

Page 57

Track

18,

Sector

Table 7.

2040,

3040

BAM

FORMAT

BYTE 0,1 2 3 0 Null flag 4-143 *l=available

O=block

(each

Track

18,

BYTE CONTENTS

144"-161

not

bit

Sector

CONTENTS

18,01 1

block

available

represents

Table 8.

one

Track Indicates

*Bit

block)

2040,

Disk

DEFINITION

and

sectoroffirst

version 1

for

future

mapofavailable blocks

3040

DIRECTORY

name

padded

DIRECTORY

HEADER

BLOCK

BYTE CONTENTS 0,1 2 3 0 Null flag 4,5 6-21 22,23 24,25 26 27,28

29-32 33-255

38,0 67

0 Unused.

160

50,67

160 0 Nulls,

Track

ASCII

Disk

name Shifted Disk ID. Shifted ASCII

format Shifted

and

not

DEFINITION

sectoroffirst BAM block.

character

for

spaces.

space.

representation

type.

spaces.

future

padded

used.

C indicating

DOS use.

with

shifted

for

2C which is DOS version

8050

spaces.

format.

and

Page 60

Table

12.

8050

BAM FORMAT

First

BAM

block:

BYTE CONTENTS DEFINITION

Track

38,

Sector

0,1 2 3 4 5 51 Highest

7-10

11-255

Second

BAM

BYTE 0,1 39,1 Track 2 3

38,3 67 0 1

block:

Track

CONTENTS DEFINITION

67 0 Null flag for

Track ASCII character C indicating Null flag for Lowest

Numberofblocks unusedontrack Bit map representationofavailable blocksontrack

*BAM for tracks

38,

Sector 3.

ASCII character C indicating

Lowest

and

sectorofsecond

future

track

number

track

number+1in this

2-50,

and

sectoroffirst

future

track

number

BAM

block.

8050

DOS use.

represented in this

BAM

5 bytes

DOS use.

represented this

per

DIRECTORY

Track

18, 39,

and entry entry entry entry entry entry entry entry

Sector Sector

1 for 1 for

sectorofnext 1 2 3 4 5 6 7 8

ENTRY

4040 8050

DEFINITION

directory

DEFINITION

block.

1,2 3-18

19,20

22-25 26,27

28,29

128+type

File

type

OR'ed

TYPES:

Track

and File name Relative file

block. Relative file Unused.

Track effect.

Numberofblocks in file: low

and

with

$80toindicate

DELeted 1 = SEQential 2 = PROGram 3 = USER 4 = RELative

sectorof1st

padded

only:

sectorofreplacement

data

with shifted spaces.

track

and sector for first side

Record size.

properly

block.

file when OPEN@ is in

byte,

high

byte.

closed file.

sector

Page 63

Table

14.

SEQUENTIAL

FORMAT

BYTE

0,1

2-256

BYTE 0,1 2-256

Track

and

254

bytesofdata

Track 254

tokenized).

and

bytesofprogram

sectorofnext

with

Table

15.

sectorofnext

Endoffile is

DEFINITION

sequential

carriage

PROGRAM

info

returnsasrecord

DEFINITION

blockinprogram

stored

markedbythree

in CBM

data

FILE

block.

FORMAT

file.

memory

zero

terminators.

format

bytes.

(with

key

words

Page 64

SYNC

NOTE:

Nottoscale

IDl

ID2

TRACK

SECTOR

CHECK-

SUM

GAP

SYNC

POINTERSTOLINK

TOGETHER

WITHIN A

• t

,...;

r..:I r..:I

E-<

P=I

254

ALL

FILE

BLOCKS

BYTES

DATA

CHECK- GAP

SUM

Figure 4 -

Figure 4 illustrates an expanded view In addition

characters. Blocks within

block pointer. By pointing

system

file triggers a search for

related blocks until

2040,3040,4040

other information, each sector contains a data block consistingof256 stored

the

Format: Expanded Viewofa Single Sector

a single sector on a diskette formatted for

same file are linked together by means of a two character

the

locationofthe

retrieve data from non-contiguous blocks. Retrieving

the

next data block which, in turn, utilizes block pointerstolocate

the

entire fileisassembled and made available for display. All PRG,

SEQ, and USR files utilize this format.

A data block numbered 1 to 35 while an

addressed by track and sector. A 2040 diskette contains 35 tracks (or rings)

8050

diskette contains 77 tracks numbered 1to77. The number of sectors per track will vary (as illustrated in Table ference and recording frequency.

the

first

The 2040 maintains a system file on track

BAM,

and file directory. The and occupied storage locations

resident in

diskette. The last

the diskette name and ID. The file directory begins on

next data block, block pointers enable the

the

first data block within a

duetodifferences in track circum-

which contains

128

bytesofsector 0, monitors available

128

the

BAM, diskette name, ID,

bytes of sector 0 are usedtostore

next sector, sector 1.

the

2040.

Page 65

SYNC

NOTE:

Nottoscale

IDI

ID2

TRACK

SECTOR

CHECK-

SUM

GAP I SYNC

POINTERS TOGETHER WITHIN A

+ +

,...,

t-< t-<

I:Q

LINK

ALL

BLOCKS

FILE

254

BYTES CHECK- GAP

DATA

SUM

Figure 5 - 8050

Figure In addition to

5 illustrates an expanded view

other

information, each sector contains a data block consisting characters. Blocks within the same file are linked together block pointer. By pointing system to retrieve data from non-contiguous blocks. Retrieving file triggers a search for the next data block which, in

the

related blocks until

entire fileisassembled and made available for display. All PRG,

Format:

a single sector on a diskette formatted for the 8050.

the locationofthe

Expanded Viewofa Single Sector

meansofa two character

data block, block pointers enable

the

first data block within a

turn,

utilizes block pointers to locate

256 stored

the

SEQ, and USR files utilize this format.

A data blockisaddressedbytrack and sector. A 2040 diskette contains 35 tracks (or rings) numbered 1 to of sectors per track will vary (as illustrated in Table

35 while an 8050 diskette contains 77 tracks numbered 1

duetodifferences in track circum-

77. The number ference and recording frequency.

The

8050 maintains system files

name, ID, and file directory. The BAM, resident in

tracks 38 and 39 which contain

the

first 255 bytesofsectors 0 and 3

the

BAM, diskette

track 38, monitors available and occupied storage locations on diskette. The file directory header block, beginning the first

30 bytes.

sector 0oftrack 39, contains the diskette name and ID within

Page 66

Chapter

ADVANCED

FILE HANDLING

the preceding chapters, you learned how to manipulate files on the disk, and were shown the format of commands used to create and update files. In this chapter, you will utilize these skills in a file handling application using random or relative access.

SPECIAL OPEN AND CLOSE

STATEMENTS

The BASIC statements (after initializing the disk):

OPEN2,8,4,

open a channel to one buffer, to be used with the block commands. In the first example, the first available buffer is allocated to channel 4. The second example cate buffer

dition position dependent code

Execute a mitted or read operations

generated. The explicit buffer allocation can be used to reserve a buffer for

GET#

the buffer number. A buffer number may only be obtained PRIOR

"#"

"#12"

12tothe channel. If the buffers are

asinthe case of an EXECUTE command.

statement to find the number of the allocated buffer. The byte trans-

that

buffer.

not

available, a

FOR DIRECT ACCESS

an attempt to allo-

CHANNELS error con-

any write

The CLOSE statement clears the OPENed channel and writes the was

last used by that channel. To avoid confusion, limit yourselftoaccessing one drive with

any direct access channel.

BAM

to the diskette that

Page 67

RANDOM

Since the BLOCK-ALLOCATE command returns the next available diskette block through

the error channel, it can be used in the allocation of records. This feature allows creating a

random file without being concerned with the actual physical structure of

However, the allocated blocks must first be recorded in a sequential or user file in order to

be referenced by the BASIC program.

The following random file example demonstrates the use that the record A smaller application might take advantage of the

Chapter 9 contains a complete listing of the random access program entitled "Random

1.00". The example program record access through BASIC programming. Most of the programming below line 2000 relative record access. The field accessing routines left-justify binary and alpha fields, and right-justify numeric fields.

In an actual situation, the program should generate error messages to the operator, or automatically take corrective action such possible including field markers, must be less than 254 characters. Field size characters becauseofthe restrictions of the BASIC INPUT# statement. Longer fields could be used if

would be much slower.

and

commands are used. These commands are used since more than one

stored in a block, and itisnecessary to manage end-of-record pointers in BASIC.

B-R

built upon a relative record scheme and provides single

rounding numbers

add data sorts and searchesaswellaskey fields to the program. Record size,

the

BASIC program were modifiedtouse GET# for retrieval

and

ACCESS

block access commands. Notice

B-W

commands.

fit a field.

restrictedto80

but

EXAMPLE

the

diskette.

would also be

that

procedure

Two sequential files are used

bears the name of the file name given in the CREATE file code (lines 1100 six-character extension. Since primary file names are ten or less characters, the file names are padded with spaces. The two files are named FILENAME .DESCR and FILENAME

.KEY01.

The descriptor ( .DESC) contains information about record structure and location. The primary key file ( .KEY01) contains the first field of each record and the relative record number. This example allows the random records to reside on a separate diskette from the sequential support files, thereby providing added room for random data. The OPEN code (lines 1200 to 1275) requires the disk

Note that since no file name be

performed on the disk containing the random data. In order to backup the disk, a

BACKUP or DUPLICATE must be performed, since the filename.

STEP 1: Insert the TEST/DEMO disk in drive STEP 2: Type: OPEN15,8,15 and press RETURN

Opens the command channel and initializes the diskette.

support the random access file in this example. Each file

1180) plus a

of the random file disk for comparison.

assignedtothe random blocks, a VALIDATE should never

DOSisunable to

COpy

without a

Create

A File

STEP 3: Type: LOAD"O:RANDOM 1.00",8 and press RETURN

the

This command loads

random access program.

Page 68

STEP 4: Insert a blank diskette into drive

STEP 5: Type: PRINT#15,"N1:MAILING LIST" STEP

Type: RUN and press RETURN

YOU

The screen displays: "DO

STEP 7: Type: Y and press RETURN

The screen displays: "RANDOM FILE NAME"?

STEP 8: Type the file name: PHONE LIST and press RETURN

The screen displays: "KEY FILE DRIVE NUMBER"?

STEP 9: Type: 1 and press RETURN

The screen displays: "RANDOM FILE NUMBER"?

STEP 10: Type: 1 and press RETURN

The screen displays: "ENTER

STEP 11: Type:

The screen displays: "NUMBER OF RECORDS"?

STEP 12: Type: 10 and press RETURN

For this example, ten

records the file can contain.

than ten.

and press RETURN

was

entered since thisisthe

WISH

OF RANDOM DISK"?

less records are needed, specify a number less

and press RETURN

CREATE A FILE"?

MAXIMUM

number of

The screen displays: "NUMBER OF FIELDS PER RECORD"?

STEP 13: Type: 4 and press RETURN

This

the number of 'items' each field contains.

The screen displays: "INPUT FIELD NAME, FIELD SIZE, FIELD TYPE".

TYPES: O=BINARY, l=NUMERIC, 2=ALPHA

1?"

FIELD FIELD

FIELD

enter: NAME,20,2

2?"

enter: PHONE,15,2

3?"

enter: ADDRESS,40,2

4?"

enter: COMMENTS,40,2

and press RETURN and press RETURN and press RETURN and press RETURN

To Add A Record

STEP 1: The screen displays: "WHOSE RECORD

Press RETURN. The screen displays: "****ADD RECORD****"

NAME"?

YOU

WISH

TO SEE?

STEP 2: Type: COMMODORE and press RETURN

The screen displays: "PHONE"?

Page 69

STEP

3: Type: 727-1130 and press RETURN

The screen displays: "ADDRESS"?

STEP

4: Type: 3330 SCOTT BLVD SANTA CLARA CA. 95051

The screen displays: "COMMENTS"?

STEP

5: Type: MANUFACTURES MICROCOMPUTERS and press RETURN

The screen displays: Press RETURN

The screen displays: NAME"? Enter the desired name. For example: SMITH and press

RETURN PHONE"? Enter the phone number: 999-356-1012 and press RETURN

ADDRESS"? Enter the address: 247 MASSOL DR LOS GATOS and press RETURN

COMMENTS"? Enter a comment. For example: MANUFACTURES PERIPHERALS and press RETURN

STEP 6: The screen displays: "WHOSE RECORD

Press RETURN

"WHOSE RECORD

"****ADD RECORD****"

YOU

and press RETURN

WISH

TO SEE"?

WISH

SEE"?

CA.

95030

The screen displays: "****ADD RECORD****"

NAME"? Enter the desired name. For example: JONES and press RETURN

PHONE"? Enter

ADDRESS"? Enter the address: 4086 AMBER and press RETURN

COMMENTS"? Enter a comment. For example: COMPUTERS and press RETURN

The computer displays: "WHOSE RECORD Enter: COMMODORE and press RETURN

After displaying the record, the screen displays:

STEP

1: Type: YES

the

phone number: 999-268-1795 and press RETURN

and press RETURN.

YOU

WISH

"ANY MODS"?

WAY

SAN JOSE

MANUFACTURES

To See A Record

TO SEE"?

Change

A Record

CA.

95117

The screen displays: Enter the number of the field you wishtochange.

"WHICH FIELD"?

Page 70

STEP

2: Type: 4 and press RETURN.

The computer displays

STEP

3: Press RETURN.

The screen display asks if there are; "ANY MODS".

STEP

the recordiscorrect, type:

The screen displays:

Type:

The computer displays the directory.

The computer displays; Type:

IDIR and press RETURN

and press RETURN. The program ends.

"WHOSE RECORD

that

"WHOSE RECORD

field:

HEADQUARTERS

and press RETURN

Getting The Directory of Listings

YOU

WISH

TO SEE"?

Ending The Program

YOU

WISH

TO SEE"?

RELATIVE FILES 4040, 8050

Direct access of relative filesisa method that allows the programmer to positiontoany record on the disk relative dard procedure becomes apparent the amount of time required to find a specific record stored on disk. This reduction in the amount of time required to locate and fetch a file through the application

handling techniques frees the user from the major objection

excessive "look

DOS

Both ficantly reduce the amount

The two main components of a relative file are the side sector chain of blocks and the data

block chain. Both are linked together through forward pointers similar

sequential file. Record sizes, while fixed in length, may range from one to 254 bytes. The

number of records not exceed 65,535.

The side sectors do blocks. The record size dictates where the pointer enced because the record size

placed when a record numberisgiven through the RECORD command. The side sector also contains a table of pointers to all of the other side sectors within the file. In order to move from one side sector to another, the pointer

command, and the corresponding side track and sector read into memory.Byusing the information contained in the referenced side sector, the data block pointer can be located and used to read in

having to search each track and sector for the desired information and it that

up"

2 and 2.5 (4040 and 8050) are capable of handling relative files and should signi-

not

the

the beginning of that file. Compare this methodtothe stan-

such a relative handling method would result in a great reduction in

relative file

using sequential disk files:

time.

time spent retrieving disk files.

those used in a

limited to

contain record information, but do contain locations of the data

actual data block containing the record. The relative file data block

the

capacity of the disk but for practical purposes should

placed when a record numberisrefer-

used in an algorithm to compute where the pointer

referenced through the appropriate

DOS

Page 71

pointers in disk read

the

side sectors allow

commands-a

considerable savings in

sired data block when compared

the

DOStomove from one recordtoanother within

the

amountoftime requiredtofind a de-

sequential methods.

two

A file may contain up data blocks. Therefore, 182,880 to

bytes (120 pointers/side sector *6 side sectors *

be greater

than

six side sectors and each side sector may contain pointersto120

the

largest file on the 204 Dual Drive

the

total storage capacityofthat

16.

Table

RELATIVE FILE FORMAT

particular disk.

DATA BLOCK

BYTE DEFINITION

0,1 2-256

Track and sectorofnext

254

bytesofdata.

the

ones) in

first byte followed by00(binary all zeros)

the endofthe

(00).

nulls

Empty

record. Partially filled records are padded with

data

SIDE SECTOR BLOCK

BYTE

0,1 2 Side sector number.

Track and sectorofnext

DEFINITION

side sector block.

(0-5)

Floppy

254

bytes/block) which happens

Disk contains

block.

records contain

(all binary

3 Record length. 4,5 6,7 8,9 10,11 12,13 14,15

16-256

Track and sectoroffirst side sector (number 0)

Track and sectorofsecond side sector (number 1) Track and sectorofthird side sector (number 2) Track and sectoroffourth side sector (number 3) Track and sectoroffifth side sector (number 4) Track and sectorofsixth side sector (number 5) Track and sector pointers

120

data

To expand a relative file, a programmer may reference the last record

the

through records from automatically generated by necessary For

example, if

number referenced would expand it

RECORD command and printtothat

the

pointofthe

contain a file, regardlessofsize,

the

current sizeofthe

current endofthe

the

DOS. This includes any side sectors and all

relative recordisone

125

blocks, then an additional side sector would be

generated by the DOS since one side sector can only represent

particular record. The intermediate

filetothe reference record

but

within the capacity limitsofthe

data

block long and

120

data

blocks.

number

blocks.

generated

number

data

will be

blocks

diskette.

the

record

Page 72

Spanningisa key feature of relative files which aids in reducing the number of disk read/ write operations required to find and retrieve data. Before explaining how this feature DOS

2 and 2.5 improves time utilization efficiency,weneed to examine how I/O channels

are utilized by relative files:

When

a channelisopened to a previously existing file, the DOS will position to

that

the first record provided

not

length variable

necessary on the OPEN if the fileisalready in existence, but

the DOS causes a check to be made against the record size

made in the 50-record

PEN statement creating the file.Ifthese do not match, then error

not present-will be generated.

the given parameters match properly. The record

that

was originally

The relative channel requires three memory buffers from the system, whereas sequential files only require two. Since there are twelve channels in the system and two of these are used in directory searches and internal functions, only three

relative channels can be open

ten, which limits the total number of channels which can be open at

time.

was

foundtobe on the boundary between two data blocks,

a record

be used anyone

one time. The highest numberofbuffers

that one data block and finishing in another, then the DOS would read the first segment as

any following records in the second data block. In practice, the records of most relative

that

can

is, starting in

well

data files will span across data blocks. The only exceptions are record size 1, 2, 127, and

254. These divide evenly into the 254 size of the data block and spanning

unnecessary. This method of spanning has the advantage of requiring no system memory overhead aside from

that

required for the side sector blocks in the relative files. When a recordiswritten upon through the PRINT#statement, the data block only written

out

when the DOS moves beyond the particular data block in which

not

immediately written out.Itis

that record resides. This can occur through successive printing to sequential records, or when positioning to another record outside of

that

particular block.

Because of the spanning feature, it tive file at the same time if either channel will be writing made in the channel's particular memory buffer area, but the change may

that

disk until the DOS moves ever, and

certain instances where the fileisonly read from, it may be advantageous to

particular data block. Thereisno restriction on this, how-

recommended that two channels not be open to a rela-

the same file. An update may be

not

be made on

have more than one channel open to a single relative file.

The

DOS

terminates printingtoa record by detecting the EOI signal whichisgenerated with

each PRINT# statement.

51-record

overflow-will be generated. Any data overflow will be truncated to fit the num-

the PRINT statement goes over the maximum record size, error

ber of characters specified by the record size and the DOS will position to the next record in

sequence.

positions within

record for input the EOI signal non-zero terminator such

the print statement contains less characters than the record size, the remaining

that

record will be filled with nulls. Consequently, when positioning to a

generated from the DOS to the computer when the last

transmitted. Should the programmer desiretostore binary information, a record

carriage return will have to be used and the record size increased by one

charactertoaccommodate the terminator. While

the

DOS

is generating new data blocks for relative files, the requested record number

compared to the number of data blocks left on the diskette.Ifthe resulting number of

data blocksisgreater than whatisleft on the diskette, then error

52-file

too large-is

generated.

Page 73

CREATING

A RELATIVE FILE

The following examples apply only to those users equipped with

2. In terms computer and a 4040 or 8050 for the disk drive.

When mer

space on the diskette for the future data. A simple program

illustrated below:

In the preceding example, line 110 creates a file with the name FILE1 and a record length of 50.

hardware, this means a 4000 or 8000 Series PET or

a relative fileisopened for the first time, the file should be initialized by the program-

allow for faster subsequent access, and to assure that the

110 DOPEN#1,"FILE1",DO,L50

120 GOSUB 190 130 RECORD#1,100 140 GOSUB 190 150 PRINT#1,CHR$(255); 160 GOSUB 190 170 DCLOSE#l

180 END 190 IF DS<20 THEN RETURN 200 PRINT DS$ 210 IF DS=50 THEN RETURN 220 STOP

both

BASIC 4.0 and DOS

CBM

must be usedasthe

DOS

reserves sufficient

perform such initialization

160

Lines 120, 140, and gramming practice to check the error channel after each disk-related operation.

Line 130 positions the file pointer message 50 RECORD NOT PRESENT a warning rather than an error condition. This messageisnormally expected to occurasa warning when a new record or GET operation should be attempted.

Line 150 causes record number written. During this write operation, the exist, and automatically initializes them by placing CHR(255) in the first character.

Line 170 closes the file and causes the space

190-220

Lines line 190 would return control to the main program. Line 200 prints the error message, and lie 210 returns to the main program if the message some other unexpected error (suchasa read error) occurs, line 220 will halt the program so the user can correct the problem.

Mter

the file has been initialized, data may be written to the file. Initialization of a file in this manner need be performed only once when the file wishes to expand an existing file, the same procedure would be used, with the record number (line 130 in the example) changed to be the new last record.

are the error subroutine.IfDSisless than 20, no error condition exists, so

cause the error handling subroutine to be executed. Itisgood pro-

record number 100 which does

will

occur at this point, but shouldbeinterpreted

accessed for the first time and indicates that no INPUT

100

(because of the pointer positioned by line 130) to be

DOS

detects that records 1 thru 99 do

be allocated in the

was

50 RECORD NOT PRESENT.

EXPANDING

originally created.Ifthe user

not

yet exist. The

not

already

BAM

and file directory.

A RELATIVE FILE

Page 74

The following example, when with the disk containing the file FILE1 (with 100 records) in

drive 0, will result in the first 100 records remaining unchanged and records containing

only CHR$(255) would be generated for records

110 DOPEN#1,"FILE1",DO,L50 120

GOSUB 130 RECORD#1,200 140

GOSUB 150 PRINT#1,CHR$(255)

GOSUB

160 170 DCLOSE#l

END

180 190 IF DS<20 THEN RETURN 200 PRINT DS$ 210 IF DS=50 THEN RETURN 220 STOP

NOTE: al. error condition

When sectors are transparent to the user since they are automatically generated and accessed by the

When

specified, it must match the record length set at the time the file

a fileisexpanded in this manner, the required side sectors are also created. Side

DOS.

190 190 190

DOPENisused onanexisting file, specification of the record lengthisoption-

will

result.

101-200.

was

created or an

ACCESSING A RELATIVE FILE

In ordertomake the relative file system practical, the user must be able to access the file for reading and writing of data. Both of these operations are simplified by relative files and both may use the RECORD command for positioning to the desired record before the operation.

To write data

(line 130)

110 DOPEN#1,"FILE1",DO 120

GOSUB

130 RECORD#1,25

GOSUB

140 150 PRINT#l,"RECORD 160

GOSUB 170 DCLOSE#l 180

END 190 IF DS<20 THEN RETURN 200 PRINT DS$ 210 IF DS=50 THEN RETURN 220 STOP

The resulting record would appear

a predetermined recordina file, a constant may be usedinthe positioning

follows:

190

25"

190

follows:

12345678901234567890123456789012345678901234567890 RECORD 25* Where * represents a carriage return ( CHR$(13)

234

Page 75

The following program illustrates the feature which permits access to individual bytes within

a record:

110 DOPEN#1,"FILE1",DO 120

GOSUB

900

130 RECORD#1,25,1

GOSUB

140 150 PRINT#l,"FIELD 160

GOSUB

900

170 RECORD#1,25,10

GOSUB

180 190 PRINT#l,"FIELD 200

GOSUB

900

210 RECORD#1,25,30

GOSUB

220 230 PRINT#l,"FIELD 240

GOSUB

900

250 DCLOSE#l

END

260 900 IF DS<20 THEN RETURN 910 PRINT DS$ 920 STOP

Lines 130, 170, and 210 cause the file pointer to

number 25. The following illustration

25 after the above example

executed:

a representation of the contents of record number

moved to different places within record

234

12345678901234567890123456789012345678901234567890 FIELD 1* FIELD 2* FIELD 3* Where

NOTE:Itis

* represents a carriage return ( CHR$(13)

important that the fieldsbewritteninsequence, since writing to a byte at the

beginning of the record destroys the rest of the record in memory. For example, this means

that while it

possible to position and write first to byte 1 and then to byte 20, itisNOT

possible to first write byte 20 and then byte 1.

Since the carriage returnisrecognizedasa terminatorbythe

data may

retrieved by the following sequence:

BASIC

INPUT statement, the

110 DOPEN#1,"FILE1",DO 120

GOSUB

290 130 RECORD#1,25 140

GOSUB

290 150 RECORD#I,25,I:GOSUB 290 160 INPUT#I,A$:GOSUB 290 170 RECORD#1,25,10:GOSUB 290 180 INPUT#l,B$:GOSUB 290 190 RECORD#I,25,30:GOSUB 290 200 INPUT#I,C$:GOSUB 290 210 DCLOSE#1

END

220 290 IF DS<20 THEN RETURN 300 PRINT DS$ 320 STOP

Page 76

Lines 160, 180, and 200 cause the stored values on disk toberead and stored in A$, B$, and C$, respectively.

extremely usefultobe abletoaccess a record whichisdetermined during program

operation. The following routine illustrates a procedure to query the operator for a record

number and data and to write the data

100 PRINT "TYPE RECORD NUMBER

the disk file:

AND

DATA" 105 INPUT R,D$ 110 DOPEN#1,"FILE1",DO

120

GOSUB

190 130 RECORD#l,(R) 140 GOSUB 190 150 PRINT#l,D$ 160

GOSUB

190 170 DCLOSE#l 180

END 190 IF DS<20 THEN RETURN 200 PRINT DS$

220 STOP

Line 130 positions the file pointer variable used in the RECORD command must

record number (R), specified by the user. Note that a

enclosedinparentheses.

Line 150 causes the data stored

The RECORD command may be omitted if the file saves

time during program execution.Anexample of this occurs when writing a large data base to the disk file. Assume that the program has already dimensioned D$ which contains 100 elements. These elements are to be written to the disk ber 1 thru 100 of file

FILEl.

D$ tobestored on the disk.

istobe

accessed sequentially, which

an array

records num-

This couldbeaccomplished with the following program

segment:

110 DOPEN#1,"FILE1",DO

GOSUB

120

130 FOR

1=1

190

TO 100 150 PRINT#l,D$(I) 160 GOSUB 190 165 NEXT I 170 DCLOSE#l 180

END 190 IF DS<20 THEN RETURN 200 PRINT DS$ 220 STOP

Since the record pointer the first record written.Ifno RECORD commandisexecuted the

automatically set to record 1 when the fileisopened, record 1

DOS

automatically posi-

tions to the next record after each PRINT. Therefore, the contents of D$ will be written to

records 1 thru 100 of the file.

For detailed description of related the BASIC 4.0 reference manual.

BASIC

commands, refer to chapter 4 of this manual and

Page 77

Chapter

SIMPLIFYING THE USE OF

COMMODORE DISK-

RELATED COMMANDS

It has been explained command and enclosed in quotation marks. This is true,

grammed

The first file on the TEST/DEMO diskette contains a program called UNIVERSAL WEDGE, often referred

takes care of can use the quick load procedure to load the equipped with BASIC 4.0, the following procedure

Start with a cold start condition by resetting both the computer and disk drive and insert

the TEST/DEMO disk in drive 0. STEP

perform these tasksaswellashowtoload and run programs stored on diskette.

the

Type:

The screen displays:

that

all disk commands mustbepreceded with the BASIC PRI1'.1'=

but

your computer can be pro-

as DOS

tasks mentioned above. If your computer has Commodore BASIC 4.0 you

LOAD"*",8

S'L"PPORT.

and press

THE

This program, when loaded into memory,

DOS

RETCR~.

DOS SUPPORT PROGRAM

SL"PPORT

will

work:

program.

For

those of you

not

Page 78

STEP 2: Type: RUN and press RETURN.

DOS

This will cause the locate itself into the top of the user memory, where it will coexist with programs which are entered later.

puter entry of disk commands.

reset. The following special symbols, once implemented, will simplify the

Support programtobe executed. This program will re-

DOS

support will not needtobe

reloaded until the com-

USING THE DOS SUPPORT SYMBOLS: > AND @

Once

DOS

SUPPORTisimplemented, preceding disk commands with PRINT#lfn or enclos-

ing

them in quotation marksisno longer required: precede the disk command with either the greater than symbol symbol.

(»

or the at-sign (@). The examplesinthis manual use

the>

Examples:

The OPEN statement The>

with LOAD"$dr",8 but this command destroys any program you might have in memory. When the data

Examples:

NOTE: To avoid scrolling the directory, press the space bartostop the listing. To continue the listing, press any key on the keyboard.

To stop a directory listing and return

The third use of >

symbol can alsobeused to load a diskette directly. Normally the directoryisloaded

you use

>10 >SO:FILE1

the>

the computer's memory.

>$0 >$l:Q*

the same

NOT required before a statement.

symbol, the directoryisprinted directly to the screen, thus preserving

the request of error messages.

the same

means display the entire directory of drive meanstodisplay

PRINT#l,

BASIC, press RUN/STOP.

"10"

PRINT#15, "SO;FILE1"

all

the files on drive 1 that begin with a

Example:

Use number

Example:

equivalent to:

10 OPEN2,8,15 20 INPUT#2,A$,B$,C$,D$ 30 PRINTA$,B$,C$,D$

LOADING A PROGRAM WITH THE I

the slash (I)toload a program from diskette. Both diskettes are searched if the drive

not specified.

/ACCT

loads the program

ACCT

into the computer's memory.

Page 79

LOADING AND RUNNING A PROGRAM

WITH

ARROW

The up arrow

searched if necessary. Example:

The

DOS

1. The program must be reaccessed from the disk whenever resetting the computer.

DOS is, they may NOT be used in a program.

3. The disk directory may be printed on the printer by

(t)

loads a program from a diskette and executes it. Both diskettes are

tJDATA

SUPPORT program has certain limitations. These are:

Support may only be used when communicating with the disk in direct mode. That

LOAD OPEN 4,4:CMD4:LIST PRINT#4:CLOSE 4

"$0",8

loads and runs the program JDATA.

SPECIAL DOS SUPPORT

giving

these commands:

INFORMATION

NOTES

Page 80

Chapter

ERROR

MESSAGES-

PATTERN MATCHING

FILE

NAMES-

DISK COMMANDS

REQUESTING ERROR MESSAGES:

The execution of the following program displays the error on the computer screen and resets

the

device error indicator:

COMMODORE

DISK DRIVES

CBM

Series 2001

CBM

Series 3000

with

BASIC 3.0

U::1

OPEt·~

INPUT#l..A..B$JC..D

PRINTA..B$..C..

where A=error message number B$=error message C=track D=sector

1J 8..15

CBM CBM

BASIC 4.0

Series 8000 Series 4000

with

Page 81

SUMMARY

CBM FLOPPY ERROR

o OK, no error exists.

1 Files scratched response. Not an error condition. 2-19 20 Block header 21 Sync character not found. 22 Data block 23 Checksum error in data. 24 Byte decoding error. 25 Write-verify error. 26 Attempt 27 Checksum error in header. 28 Data extends into next block. 29 Disk

30 General syntax error. 31 Invalid command. 32 Long line. 33 Invalid filename. 34 39 Command file 50 Record 51 52 File too large. 60 File open for write.

61 File

62 File not found. 63 File exists.

64 File type mismatch. 65 No block. 66 illegal track or sector.

67 illegal system track or sector.

70 No channels available.

72 Disk full or directory full.

73 Power up message, or write attempt with DOS mismatch.

74 Drive not ready. (8050 only)

Unused error messages: should be ignored.

not

found on disk.

not

present.

write with write protect on.

mismatch.

file given.

not

found.

not

present.

Overflow in record.

not

open.

Directory error.

MESSAGES

DESCRIPTION

NOTE: Error message numbers less than 20 should be ignored with the exception of 01

gives

which

20: READ ERROR (block header not found)

21: READ ERROR (no sync character)

information about the number of files scratched with the SCRATCH command.

The disk controller by an illegal sector number, or the header has been destroyed.

The disk controller misalignment perly seated diskette. Can also indicate a hardware failure.

unabletolocate the headerofthe requested data block. Caused

unable to detect a sync mark on the desired track. Caused by

the

read/write head, no disketteispresent, or unformatted or impro-

DOS

ERROR

MESSAGES

Page 82

22: READ ERROR (data block not present)

that

The disk controller has been requested to read or verify a data block

was

properly written. This error message occurs in conjunction with the BLOCK commands

and indicates an illegal track and/or sector request.

23: READ ERROR (checksum error in data block)

This error message indicates that there

data has been read into the

DOS

an error in one or more of the data bytes. The

memory, but the checksum over the dataisin error.

This message may also indicate grounding problems.

24: READ ERROR (byte decoding error)

The data or header has been read into the

DOS

memory,

but

a hardware error has been

created due to an invalid bit pattern in the data byte. This message may also indicate

grounding problems.

25: WRITE ERROR (write-verify error)

This message

and the data in the

generated if the controller detects a mismatch between the written data

DOS

memory.

not

26: WRITE PROTECT

This messageisgenerated when the controller has been requestedtowrite a data block

while the write protect switch

depressed. Typically, thisiscaused by using a diskette

with a write protect tab over the notch.

27: READ ERROR (checksum errorinheader)

The controller has detected an error in the header of the requested data block. The block has not been read into the

DOS

memory. This message may also indicate ground-

ing problems.

28: WRITE ERROR (long data block)

The controller attempts

block.

the sync mark does not appear within a pre-determined time, the error

detect the sync mark of the next header after writing a data

messageisgenerated. The erroriscaused by a bad diskette format (the data extends into the next block), or by hardware failure.

29: DISK ID MISMATCH

This messageisgenerated when the controller has been requested to access a diskette which has not been initialized. The message can also occur if a diskette has a bad header.

30: SYNTAX ERROR (general syntax)

DOS

The

caused by an illegal number of file names, or patterns are illegally used. For example,

two file names may appear on the left side of the

cannot interpret the command sent to the command channel. Typically, this

COpy

command.

31: SYNTAX ERROR (invalid command)

The

DOS

does not recognize the command. The command must start in the first

position.

32: SYNTAX ERROR (long line)

The command sent

longer than 58 characters.

33: SYNTAX ERROR (invalid file name)

Pattern matching

invalidly used in the OPEN or SAVE command.

Page 83

34: SYNTAX ERROR (no file given)

was

The file name

left out of a command or the

Typically, a colon (:) has been left

out

of the command.

DOS

does not recognize itassuch.

39: SYNTAX ERROR (invalid command)

This error may result if the command sent

15)

unrecognizable by the DOS.

command channel (secondary address

50: RECORD NOT PRESENT

Result of disk reading past the last record through INPUT#, or GET# commands. This message will also occur after positioning

file. If the intent

mand), the error message may after this error

to expand the file by adding the new record (with a PRINT# com-

ignored. INPUT or GET should notbeattempted

detected without first repositioning.

a record beyond end of file in a relative

51: OVERFLOW

RECORD PRINT# statement exceeds record boundary. Information riage return which

message

will

sentasa record terminatoriscounted in the record size, this

occur if the total characters in the record (including the final carriage

return) exceeds the defined size.

52: FILE TOO LARGE

Record position within a relative file indicates that disk overflow

60: WRITE FILE OPEN

This message

generated when a write file that has not been closedisbeing opened for

reading.

61: FILE NOT OPEN

This message DOS. Sometimes, in this case, a message

generated when a fileisbeing accessed that has not been opened in the

not generated; the requestissimply ignored.

62: FILE NOT FOUND

The requested file does

not

exist on the indicated drive.

63: FILE EXISTS

The filename of the file being created already exists on the diskette.

64: FILE TYPE

The file type does

MISMATCH

not

match the file type in the directory entry for the requested file.

truncated. Since the car-

will

result.

65:

BLOCK This message occurs to

allocated has been previously allocated. The parameters indicate the track and sector available with the next highest number. blocks higher in number are

66: ILLEGAL TRACK

The

DOS

has attemptedtoaccess a track or sector which does not exist in the format

AND

being used. This may indicate a problem reading the pointer

67: ILLEGAL SYSTEM T OR S

This special error message indicates an illegal system track or sector.

conjunction with the

use.

SECTOR

B-A

command.Itindicates that the block

the parameters are zero (0), then all

the next block.

Page 84

70:

CHANNEL (available) The requested channel is sequential files may be opened

have six opened files.

71: DIRgectory) ERROR

BAM

does

not

The

BAM

or the the diskette to restore the the corrective action. NOTE:

72: DISK FULL

Either the blocks on for the 2040, 3040, and two blocks are available on the 8050

has been overwritten in

match

the

diskette are used or the directoryisat

4040

not

available, or all channels are in use. A maximumoffive

one time to the DOS. Direct access channels may

the

internal count. Thereisa problem in the

DOS

memory. To correct this problem, reinitialize

BAM

in memory. Some active files may be terminated by

BAM

= Block Availability Map

its limitof152 entries

or 243 entries for the 8050. DISK FULLissent when

allow the current filetobe closed.

BAM

allocation

73: DOS MISMATCH (73,

DOS 1 and 2 are read compatible but not write compatible. Disks may be interchangeably read with either DOS, with the other version because the format

attemptismadetowrite upon a disk which has been formatted in a non-

an compatible format. (A utility routine mat to another.) This message may also appear after power up.

74: DRIVE NOT READY

attempt

diskettes present in either drive.

Pattern matching of file namesisavailable on all Commodore floppys. Pattern matching uses the question mark (?) and the asterisk (*) lar names.

The asterisk

is insignificant.

FIL* could refer

FIL or FILE1 or FILEDATA or FILLER

has been madetoaccess the 8050 Dual Drive Floppy Disk without any

usedatthe

For

example:

CBM

DOS

V2.5 8050)

CBM

DOS

(73,

but

V2 ) for 4040

a disk formatted on one version cannot be written upon

different. This errorisdisplayed whenever

availabletoassist in converting from one for-

PATTERN

perform operations on several files with simi-

endofa string of characterstoindicate

files named

MATCHING

that

the rest of the name

or any other file name starting with the letters FIL.

The question mark may be used anywhere within the string of characters the character in

or DIAGN.SRC or PROGR.SRC

but

not

that

particular position should be disregarded.

????? .SRC could refer

TSTER.SRC

SRC.FILES

files named

For

example:

indicate

that

Page 85

Both the characters and the position of the characters are significant. The question mark and asterisk may be combined in many ways:

*J??????

does not make sense because the question marks are in an area which

insignificant (be-

cause of the asterisk).

P???FIL* will access files with the names

PET FILE or PRG FILE-32 or POKEFILES$$

or any other files starting with P and having FIL

SCRATCH with pattern matching should be used

positions

carefully~

5-7.

since multiple files will be

scratched. LOAD or DLOAD will load the first file which fits the pattern matching. OPEN

or DOPEN with pattern matching may be used

open an existing first existing file encountered which fits the description will be opened. DO

PEN should notbeused with pattern matching when creating a new file. Never

RENAME~

result~

SAVE~

if attempted.

DSAVE~

COpy

for pattern matching since an error condition will

USER'S QUICK REFERENCE: DISK

The

user~s

quick reference guide will assist the userinbecoming familiar with the various commands used in both wellaswith

all

Commodore disk units.

BASIC

3.0 and BASIC

4.0~

and with the

file~

which case the

However~

COMMANDS

DOS

SUPPORT utility

OPEN or

use

In order

make BASIC 4.0 easier to

language. For

•

DSAVEand DLOAD commands eliminate the needtospecify device number each

example~

with BASIC 4.0:

use~

disk commands have been incorporated into the

time you store and retrieve disk files.

• Directory display

now a one-step procedure and no longer interferes with the

program in memory.

• It

no longer necessarytowrite a program to read the error channel. The variable

DS$ contains the error message.

• Formatting

now a one-step procedure through the

use

of HEADER command.

Commands in BASIC 3.0 are upward compatible with BASIC 4.0. That with with

BASIC BASIC

3.0~

those commands

4.0.

All

disk commands available on the 2040 are upward compatible with both

will

still work on the Series 8000 Computer furnished

the 4040 and 8050.

is~

if you are familiar

Page 86

Table

17.

User's Quick

Reference-Disk

Commands

BASIC

SAVE

"dr:fn",8

LOAD"dr:fn",8

LOAD"*",8 RUN

LOAD"dr:fn",8 LOAD"$0",8

LIST (destroys

100PEN1,8,15 20INPUT#1,A,B$,C,D 30 PRINT A,B$,C,D

NOTE: Assume mands in letter

as illustrated.

PRINT#l,

3.0

memory)

that

the

following formats. Commands

"Ix"

UNIVERSAL

DOS SUPPORT

SAVE"dr:fn",8

/dr:fn

(searches

(preserves

OPEN1,8,15 has already been

INITLIALIZE

>Ix

tdr:fn

t* >$0

return

both

drives)

memory)

maybespelled

typed

BASIC

DSAVE,

(drive defaults

DLOAD"fn

(drive defaults

DLOAD"fn" RUN

shifted RUN/STOP DIRECTORYor

DI<shifted

(preserves ?DS$or?DS

(DSisnumberoferror only)

for

allofthe

outorabbreviatedbythe

PRINT#l,

PRINT#

4.0

"fn"

,Ddr

",Ddr

,Ddr

memory)

"Ix"

com-

first

PRINT#l,"Vdr"

PRINT#l,

PRINT#l,"Cddr=sdr"

PRINT#l,

PRINT#l,"Cdr:dfn=

dr:sfn1,dr:sfn2,

PRINT#l,

"Sdr

:fn"

"Dddr=sdr"

"Cdr

:dfn=

dr:sfn"

...

"Rdr

:dfn=sfn"

VALIDATE

>Vdr

SCRATCH

>dr:fn

DUPLICATE

>Dddr=sdr

COpy

(all disk)

>Cddr=sdr

COPY (single file)

>Cdr:dfn=dr:sfn

CONCATENATE FILES

>Cdr

:dfn=dr

dr:sfn2,

RENAME FILES

>Rdr:dfn=sfn"

:sfl,

...

COLLECT

SCRATCH'

BACKUP Dsdr TO

COpy

COPY

CONCAT

RENAME Ddr,

Ddr

'fn"

Dsdr TO

Ddr,"sfn" Ddr,"dfn

Ddr,"sfn" Ddr,

,Ddr

Dddr

"dfn

"sfn"

"dfn"

Dddr

PRINT#l,"Ndr

:dname,xx"

FORMAT A DISKETTE

>Ndr

:dname,xx

HEADER

"dname",Ddr,Ixx

Page 87

Chapter

RANDOM

1.00

PROGRAM LISTING

This chapter provides a complete listing of the random access program described in Chapter 6 under the heading of Random Access Example.

F.:EAD'T'

REM

1 2 3 4 5 6

10 11 12 13 15 16

20 21 25 30 31 32 S=0:

40 I

9f1

RANDOM

REM

SUBROUTINESTOMANAGE

REM

VARIABLES

REM

...

REM

VARIABLES

REM

ALL F.:EM REM

* .

REM POKEI022, M'=CHR$(13):REM :;:;P'=" C0=2: Cl=3: CC=15: D=0: T=0:

DD=0: F.:D=f1:

D$=" NR=0: CR=0: FR=0: NF=0: CF=0: PB=0: RS=0: NB=0: E=0: REM

EN$,EMS.ET$,ES$,ET,ES EP=.5/256: AS=0: PEM

AS=0: F.:EM

"A" DN=8:0PENCC,DN,CC: GOT02000: PEt1

1.0 ARE

DEFINEDBYUSER

FUNCTIONS

128:REM

REM REM

REM

REM REM REM

REM

" :

REM REt'1 PEM#PECOPDSINR-FILE REM REM REM#FIELDS REM REM#PECOPDS REM REM#BLOCKSINP-FILE REM

PEM PEM

USE

',"'ARIABLES

REM

SET

SHOULD

ACT

TURN

FIELD DIRECT

SEQUENTIAL COMMAND CURRENT CURRENT CURRENT

DESCRIPTOR

F.:At·WOt1

PAt~DOt1

CURRENT

1ST CURPENT PECOPD EPPOP

INTEGEP INDEX

ARRAY

AF.:E

STARTOFUSER

RANDOM

FROM

DATAOFDESCRIPTOR

PROGRAM

REFLECT

UPON

THE

DOS

SUPPORT

MARKER

CHANNEL

CHANNEL CHANNEL DRIVE TRACK SECTOR

DRIVE

DF.:I'·

...

E #

DISK

RECOPD

FREE

RECORD

FIELD

PER

SIZE

FLAG,

EPROR

COPPECTI(~

ARPAY

INDEX;

REM

AS=I:

TEt'1PORAR'T'

DN=

ACCESS

DESIRED

VARIABLES

# #

RECORD

BLOCK

ADDRESSING

DEVICE

PROGRAM

FILE

3.1

UNUSED

BYTES =0

CHANNEL

T&S

NUMBEP

OFF

ARE

FILES

DEFINED

STRATEGY

FILE&KEY

STRUCTURE

"+"":

REt'1

VAPIABLES

SET,

CR=

BELOW

:;:;PACE

RECORD

LIST

FILES

...

FOR

F'ADDING

OFFSETINBLOCK

Page 88

[10

~]~:

103 1[15 110

111

115 12[1

125 130 135 14'.:1

145 146 150 151

155

160 165 17[1

175

2~X1

2~:11

202 2'.:15

210

215 220

,-,.-.e-

.:::..:::.._1

230

2*]

245

::::O~:1

:X11 3[12 305

31'.:1

315

:::2~:1

'-"-,E:"

'':''::''-'

:~:35

340 400 401 402

4~]5

415 42[1 425

43~]

435

44'.:1 45'.:1 451 452

455

46'.:1 465 470 475 4:::0 5(1'.:1

501

5f12

515 520 53(1

C='-,C'

oJ·:.·;.)

....

t.t.

F:Et1

FH1

F:H1

..t.t.t.t.t.t.t.tt...t.t.t.t.t.t.t.t.t.t.

RANDOM

1ST

SET

FILE

NR,

DIMENSION

NF&NB

ROUTINE

F:Et1

GO:::UB15'.:1 IFFP%=-lTHENRETURN FP;·;=-l

D!t'1

F:::;';

(t'~F)

F:Et1

DIt1FP;';

F:H1

1t'1FT;.;

DIt1

FH$O'W)

DH1

F$O·F'

DI~1

F(~W)

RET

UF.:

t·j

(t·jF)

(t'~F

)

:REM

FP%(I)= :REM :REM

REM :REM

FIELD FIELD

FIELD FIELD FIELD FIELD

:::IZE

POSITION

SUM

[FS%(I-l)]

TYPE:

0:BINAPY, HEADING ARGS-ALPHA,BINAPY

ARGS-Nl~ERIC

IFIT%=-lTHENRETURN IT;';=-l D

It1IT;.; DIt1I:::;'; DI DI~1RF.:;·;

RETURt·~

REM REM

FH1

GC6UB900 PF.:ItH#CC.."Ul:"C0.:

PF.:IHT#CC.."B-P:

FORCF=

GOSUB5~X1

t'~E::<TCF

PRItH#CC.."U2:

(t·m)

(m:)

(t·W)

f.t.t.t.t.f.f.tt.tttttttt.tt.tt.

UPDATE

TOt~F

t~RI

RECORD,

REM REM REM

:REM

"C0.:

"C[1.:

TRACK SECTOR PRIMARY PELATIVE

D.:

T.:

D.:

T.:

:::

INDEX

KEY

RECORD

..t.t.t

ARRAY

VALUE

GOSUB1000:IFETHEN1900 RETUF.:

t·j

REM

t.ttf.tttttttttt.t.ttttt.t.t.tt.t.

REM

READ

RECORD,

REt1

GC6UB9~X1

PF.:ItH#CC, PF:ItH#CC.."B-P:

"Ui:"C0.:

"C0;

D.:

T.:

:::

GOSUB1000IFETHEN1900

FOPCF=l

GOSUB6~Xl

t'~E::-::TCF

TOt'~F

RETUF:tj REM

t.t.t.tt.t.t.tt.t.t.tt.tt.tttttttttt.

PEM

UPDATE

FIELD(CF)

PECORD

CR, REt1 GOSUB9[10 PRItH#CC.."Ul:"C0.:

D.:

T.::3

GOSUB1000:IFETHEN1900

PI':

It-H#CC.."B-P: GOSUB500 PPINT#CC,

:REM

"U2:

"C[1.:

FP;·;(CF)+F.:P

UPDATE

"C0;D;T;S

FIELD

GOSUB1000:IFETHEN1900

F:ETUF.:t·~

REM

....

REM

ttf.tf.tttttttttttttttttt

READ

FIELD(CF)

RECORDCR.. PEM GO:::UB9[1[1 PPIt-H#CC, GC6UB pF.:nH#CC.."E:-P: GOSUB600

RETURt·~

PEM REM

100[1

"Ul:"C0.: :I

FETHEt·~

D.:

T.:

19[10

"C0.:FP;·;(I::F)+f':P

:REM

READ

FIELD

ttttttttttttttttttttttttt

UPDATE

FIELD(CF),

:::

B-P

SET

REM

IFFT%(CF)()lTHEN520 A$=RIGHT$(SP$+STR$(F(CF»,FS%(CF»:GOT0530 AS=LEFT$(FS(CF)+SP$,FS%(CF»

PRItH#C[1..AS.:

~1$:

RETUf':tj

LIST

SINGLE

PER

KEY

FIELD

UPDATE

READ

ALPHA

Page 89

6013

REM

601

REM

6132

REM

610 IF

READ

FIELD(CF),

FT%CCF)

B-P

THEN645

SET

615 Al$="" 620

FORJ=lTOFS%CCF)

625

GET#CO,

6:30

Al$=Al$+A$

6:35

NEXT:F$(CF)=Al$

640

GET#C0,A$:RETURN

A$:

IFA$=""THENA$=CHI":$O~1)

645 INPUT#C0,F$(CF) 650

IFFT%CCF)(>lTHEN

655

FCCF)=VALCF$CCF»:RETURN

700

REM

•••••••••••••••••••••••••

701

REM 7(12 70:::: 710

71~

720 725 7:30 7:35 7::::6 740

750 751

752

760

770

ALLOCATE

REM

RETUR~~ED

F.:EM

GOSUB800:IFETHEN1900:

PRINT#CC,

"B-A: "D;T;S

INPUT#CC,EN,EM$,ET,ES

IFEN=0THENRETURN IFEN()65THEN1900 IFET=18THENT=19:S=0:GOT0715

T=ET:

S=ES GOT0715 REM

•••••••••••••••••••••••••

F.:Etol

FI":EE

Ot~E

REM

GOSUB800:IFETHEN1900:

PRINT#CC,

"B-F: "D;T;S

RETURN

ONE

BLOCK,

T8::::;

BLOCK.,

T &S

AF.:E

ALLOCATED

REM

=REQUESTED

CHECK

T & S

VALUES

TRACK&SECTOR

T~~:::;=TRACK8:SECTOR

REM

CHECK

T & S

o::T=18ISSKIPPED)

780 INPUT#CC,EN,EM$,ET,Es

IFEN=0THENRETURN

785 79(1

GOTO

800 801 802 810

19(10

REM

•••••••••••••••••••••••••

REM

CHECK

MAX

REM

IFT>:35THEN1900

SECTOR

820 E=0:IFT=0THEN=40:GOT01900 840

A:3=16:I

FT):30THEt~880

850 A:3=17:IFT)24THEN880 860

A:3=19:

870

A::::=2(1

880

IFS>A:3THEN1900

89(1

RETURt~

900

REM

901

REM

902

REt1

905

D=RD

9H3

E=0

915

IFAS=-lTHENRP=CRf.RS+l:GOT0950

92(1

I":P=INT

9:30

T=IT%CRP):S=IS%CRP)

IFT)17THEN880

••••••••••••••••

SET

RECORD"S

C(CR-l )

,/RB+EP):IFF:p>t·m

••••"••

TF.:ACK,

SECTOR

~::

RECOl":D

RP<)3THEt~EN=41:

POIt-4TER

940 RP=INTCCCCR-l)/RB-RP+EP).RS.RB)+l 950

IFRP)254THEN

960

RETURt·~

1000

REM 1001 1002 1005 1010 1015 IF 1017

•••••

REM

INPUT

REt1

INPUT#CC,EN$,EM$,ET,ES

EN=VALCEN$):E=0

EN$=

ET$=STR$CET):ES$=STR$CES)

EN=41:GOT01900

,.,."

2040

"00"

THEt·~

••

,.,

ERROR

RETURN

•••"••

STATUS

1020 IFEN$(>RIGHT$("0"+MID$CSTR$CEN),2),2)THEN1070 10:30

H~=

THEN

Erl$=

11335

E=E+l 1(14(1

EM$=u

~"+EN$+U!!!

1050

IF 1060 1070 1080 1085 1

(19(1

H~{30

RETUF:~~

EM$=" EM$=EM$+EN$+EM$+ET$+ES$ E=E+l

RETUl":t~

01":

EN=65

~'r'STEM

~~OT

ET:f+""+Et'1$:

u+Et1$

THEN

F.:ESPOt·Ui

EM$=EM$+uONu+ET$+".,

t·~G

RETUF.:~~

PI":OPERL'r'"

FF.:Ot'l

GOTO

"+ES$

19(u3

nUiE:x:

ARRA'T'S

Page 90

~)(1

REM

t.****t.****t.t.*t.*t.*******t.*

REM

IHH

I1f12 1103 11(14 11(15

[16

11(19 1110

1115 1116 1120 1121 1122 1123 1124

1126

1130 1135 114(1

1145 1150 1152 1155 1160 1165 1166 1167

116:::

1170 1175 11

::::~:1

1200 1201 1202 1203 1204 12(15 12(19 1210

1215

1220

·-,·-,<::,

0::.'::',_1

1226 1227

123~:1

1235 1240 1245

1250

1255

126(1 1265 1270

·-,-,,,,

.::..

._1

12:::0 12:::5

12:::6

129~)

129::: 1299 1400 14(11 1402 14(19 1410 1420

143~)

1440 1490 1900

CREATE

REM

INPUT:

REM REM REM

REM

DRIVES

F.:Et'1

R::::=1:D=RD

FORAO=lTONF:FP%(A0)=RS:RS=FS%(AO)+RS+l:NEXT:RS=RS-l

RB=INT(254/RS+EP) OPEt·jCO.,

CiO:;UB

12:::0 PRItH#CC, "B-P: FORA0=lTORB:FORA1=lTONF PRINT#CO,LEFTS(SPS,FS%(Al»;MS; t·jD<TA1,A(l NB=INT(NR/RB+EP):IF(NR/RB-NB)t.RB)=lTHENNB=NB+l T=1:S=0:GOSUB150 FORAO=0TONB-l:GOSUB710:IFETHEN1900

IT%(AO)=T GO:::UB710 PRItH#CC, "B-P· PRINT#CO,NR;MS;I;MS;NB;MS;RS;MS;RB;MS;NF;MS; PRItH#CC, "B-(,J: AS=::::TRHDD)+":"+LEFTS(FS+:3PS, OPEt·jC1,Dt-j..C1, GO::::UB1(lIXl:IFETHHj PRINT#Cl,IDS;MS;T;MS;S;MS; FORA0=ITONF:PRINT#Cl,CHRS(FS%(A0»;CHRS(FT%(A0»;FHS(A0);MS; : FORA0=OTONB-l:PRINT#Cl..CHRS(IT%(A0»;CHRS(IS%(A0»; CLOSEC1:CLOSECO:RETURN REM

*t.'t.t.t.t.*t.t.t.t.t.t.t.t.ttt.t.tt.tt.t.

REM

OPEN

REM

INPUT: REM REM REM

DRIVES REt1 AS=:::TRS(DDH":"+LEFTS(FS+SPS, 1 OPENC1,DN,Cl,A':GOSUBI000:IFETHEN1900 INPUT#Cl,IDS,T,S

OPEtK:O.,

GOSUB12:::0

PRItH#CC.,

INPUT#C0,NR,FR,NB,RS..RB,NF CiOSUB100:FT%(0)=TFS%(0)=S

FORA0=1TONF:GOSUB129::::FS%(A0)=ASC(AS) GOSUB129::::FT%(A0)=ASC(AS)

INPUT#Cl,FHS(A0):NEXT FORA0=0TCNB-l:GO::::UBI298: GOSUB129::::IS%(A0)=ASC(AS):NEXT

GOSUB1000:IFETHENI900

CLOSECl

F.:ETURt·j PRItH#CC.."Ul:".: PRItH#CC, "B-P: CiET#CO,A',A1S:A'=AS+A1S:IFIDS()ASTHENEN=43:EMS="WRONG

F.:ETUF.:t·j CiET#C

1.,AS:I

RETURt·j

REM

t.t.t.t.tt.*t.t.t.t.t.t.t.*t.t.tt.t.*t.t.t.t.

REM

INPUT: REt1 PRItH#CC" PRINT#C0,NR;MS;FR PRItH#CC, CLC6EO:l RETUF.:t·j E=E

+1:

DESCRIPTOR FS=

FILENAME

FILE

IDS,NR,NF,FS%(),FT%(),FHS()

DD=

DESCRIPTOR

RD=

RANDOM

DISK

MUSTBEINITIALIZED

Dt-j.,

CO,

"#" :

GO:::;LIB1(11)(1:IFETHEt·j

"C0.:

IS%(A0)=SGOSUB430:NEXT

"CO.:

D.:

T.:

:::

190(1

RELATIVE

FS= DD= RD=

FILE FILENAME DESCRIPTOR RANDOM

DISK

MUSTBEINITIALIZED

Dt-L

CO,

"#" :

GO:::UB1(1I)O:IFETHHH

"B-R:

".:

C(l.:

RD.:

T.:S:GO:::UBI0(1tl:

IT;·;(A~:l)=ASC(AS)

C0.:

F::D.:".,

".:

C(l.:

FAS="

"THEt·jAS=CHRS

RELATIVE

VARIABLES

"B-P:

"CO

"B-(·j:

"C(l

1:::.,0":

162

FILE

FROM

1 MS;NB;MS;RS;MS;RB;MS;NF;MS; D.:

FT;·;(~:1).:

F.:ETUF.:t·j

FILE

DRIVE

FILE

DRIVE

1(1)+".

DRIVE

0)+".

190~:1

DESCR,

DESCR.,U..

9~)~)

IFETHEtH9(1I)

GOSUB1(1I)O:IFETHEt·H

«(1)

OPEN

SHOULDBEVALID

F:::;·;«(1)

U.,

(~"

F.:"

9(1(1

:NEXT

RAND

DISK":GOT01900

Page 91

200(1

mpUT"::m~lDO

2001

HWUT":~F.:At·mOt'1

2(H~12

t·WUT

2(H~nIt'~PUT"

2005 2(H36It·WUT" 2007 2010 2015 2(116PPI 2(119 202(1 2025 2030 2040

205~3

2055

2~390

2100 2103 2105 2110 2120 2140 2142 2145 2147 2150PPI t-n 2155 2156

216~3

2161 2165 2167

"VE'T'

PAtmOt'1

mpUT"Et-nEP I

t·~Ut'1BEF.:

t'~PUT"

t·Wt'lBEP

CiC6UB110

PPINT"~

NT"

P:::=O FOP

I =1

TOt'~F

A$=" I " : I FDD=PDTHENA$=" I "+:::TP$ (DD) PPINT#CC,A$ CiOSUB1100:IFETHEN3900 OPEtH..:::..4..:::TF.:$(DD)+": "+LEFT$(F$+SP$., PRINT#4,0;M$; CiOT02120 PEM

OPEN I t·iPUT" HWUT"

:~F:At-mot'1

KE'T'

mpUT"RAt·mOt'1

CiOSUB1200:IFETHEN3900 OPEtH..:::"

INPUT#4..RR:IFRP=OTHEN2147

FORI=1TOPp:INPUT#4..f<1$(I)..PP%(I):NEXT CLO:::E4

":1~O

PPHH"T'r'PE / PF.:

It-n"(HIT

PF.:lt-n":~lll.1,jHOSE

mpUT"~·n:::H

I FPP:i'=" IFRP$="//"THEN2400

'T'OU

~H:::H

FILE

DF.:I'·lE

FILEDPI

PECOF.:DS".:

FIELDS

INPUT

FIELD

n'PE::::

:PPI

tH"

O=B FIELD".:I., : I

:CLOSE4

RANDOM

FILE

FILEDP!'olE

FILE

4.,

:::TP$(DD)+":

PETUPt·~

OUIT)iI"

PECOF.:DDO'T'OU"

"THa~2:31

:::EE

CPEATEAFILE

t·~At'1E".:

F.:At·mOt·1

F$ t·Klt'1BEP".: ',,IE

t·~Ut·1BEF.:".:

DISf<

t·~p

PEP

F.:ECOPD".:

NAME..FIELD

t·~AP'T'..

SIZE..FIELD

=t'~U~1EP

t·WUTFH$

FOP

t·~At'1E".:

DF.T·lE

ACCESS

t·~Ut'lBEF.:".:

t~Um:EP".:

"+LEFT$(F$+SP$..1(1)+".

ADD

.'1'''.:

t:Ht·1PLE

F.:

At·mo F.:ECOPD)" PI':$

216::: IFRP$="/DIP"THENCiOSUB4000:GOT02160 2170

FORII=1TOPP:IFf<1$(II)<>PR$THENNEXT:CiOT02300

2175

CR=RR%(II):GOSUB300

218(1

FORI=1

21:::5

FF=(1

2190

It~PUT"

2195

mpUT"

22(10

PRHH"

2210

FF=1:CiOT02190

2220

IFFF=0THEN2160

2222

IFA=1THENf<1$(II)=F$(A)

2225

GC6UB2~30

2230

GOT02160

2300

PI':

2305

It-lPUT"DO

231 0

pr;~

2312

IFFR>NRTHEN2500

2315

CR=Fp:FR=FR+1:RR=RR+1

2320

FORI=1TC~F:PRINTFH$(I);

233~3

GOSUB2(1(1

2340

f<1$(RR)=F$(1):PR%(RR)=CR

2::::5(1

GOT02161:1

24(H~1

F.:Et'1

24135

CiOSUB

241(1

OPEt~4

2420

CiOSUB1(1(1(1

2430

PRINT#4,PP;M$;

2440

FOPI=1TORp:PPINT#4..f<1$(I);M$;RP%(I);M$;

2445

GO:::UB

245~~1

CLOSE4

2455

GOSUB1000:IFETHEN3900

249~)

POI<E

25(H)

PI':

TONF:

PRItHI.:")

At'~'T'

t'lODS

~,jH

ICHFIELD".:

"F$(A):

I t-n

":~F.:ECORD

'T'OU

tH"

:~lH:H

140~~1

:::.,4..

(H~H3

~H:::H

AnD

RAt·m

"I!"+STF.:$(DII)+"

: I

FETHaB9~3(1

: I

FETHEt-j::::9~~10

1022..::::am:F.:Et'1

ItH"

THE

FILEI:::

"FH$(

.11'"

: I

PF.:It-n"~"

tKiT

PECOF.:D

,::HWUTF$(A):

PF.:E:::Et-H" TO

ADD".: A$:

:H:H:~l~]"

:INPUTF$(I):F(I)=VAL(F$(I»:NEXT

FILE

: "+LEFT$(F$+:::P$..1(1)+".

TUF.l~

FULL..

DOS

t·JO

I)":"..

F$(

FLEFT$(A$..

IFLEFT$(A$..1

SUPPOPT3.1

ADD

IT 251~3CiOT0216(1 3900

PRINTE..EM$:STOP

4000

FORDI=OTONp:PPINTf<1$(DI):NEXT:PETURN

t·~.II'''.:A$:

F.:D

III''';

ID$:

t'~F

C..

2=ALPHA:~l"

( I )

F:::;'~

1(1)+".

r;~D

t'1

ACCE:::::::~l"

I):

t'~E>::T:

1)<> '"T'''

F(A)=VAL(F$(A»

)<>'''T'''THEt~2160

:NEXT

IOt~AL

Ot·~

RECOF.:D:::

IFLEFT$(A$..1)<>'''T'''THEt·Q1(10

ID$=LEFT$(

TYPE"

( I )

FT;'~

( I ) :

f<E'T'01..U.,

~.j"

f<E'T'(11..U"

PF.:HH

THEt~222(1

f<E'r'01..U.,

t1A'T'BEADDED"

ID$..2)

PS=FS;'~

( I )

+F.:S+

1 :

t'~E::<T

Page 92

power cord, 3 Advanced disk programming, 47 Advanced file handling, At symbol (see DOS Support) BACKUP (BASIC 4.0 direct command), 29

BAM,

22,47

Format

2040,3040,55 4040,56 8050,58

Memory requirements, 22

BASIC commands

CLOSE command, 39 DC

LOSE command, DLOAD command, 36 DOPEN command, 39 DSAVE command, 36 GET# command, 43 INPUT# command, 42 LOAD command, 36 OPEN command, PRINT# command, 41 RECORD# command, 43 SAVE command, 36 VERIFY command, 37

BASIC commands, disk drive, 35 BASIC 4.0 direct commands

BACKUP command, 29 COLLECT command, 28 CONCAT command, 31 COpy RENAME command, 32 SCRATCH command, 33

command, 31

Chapter

INDEX

Block availability map, 22 Block distribution, by track, BLOCK-ALLOCATE command, 51 BLOCK-EXECUTE command, 50 BLOCK-READ command, BLOCK-WRITE command, 50 Block pointer, 26 Buffer number, 65 BUFFER-POINTER command, 50 Business keyboard, Bus, IEEE, Cables, 11

PET to IEEE, 11

IEEE CHR$ function, 41, 42, 48, 49, 51, 52 CLOSE command, 39 Closing the command channel, Closing the data channel, 41 COLLECT (BASIC 4.0 direct command), 28 Command channel, Compatability

BASIC versions, 35 Disk drives with computers, 3

DOS CONCAT (BASIC 4.0 direct command), 31 COpy

COpy

Data blocks, 69 Data channel

Closing, 41

IEEE, 11,

Series 2001, 3 Series 3000, 3 Series 8000, 3

versions, 69

(BASIC 4.0 direct command), 31 command, 31

14,17

Page 93

Data file

Concatenation, Copying, 29 Renaming, 31

Data handling, 35

BASIC commands for, 35 DCLOSE command, 40 DEMO

Description of Descriptor (.DESC), 66 Device number, 35 Diagnostic boot, 18 Direct access, 65

Directory, 26

DIRECTORY (BASIC 4.0 direct Directory format, 60

Directory header

Directory header block, 8050, 57 Diskettes

Disk maintenance commands, 23

Disk maintenance commands

diskette (see TEST/DEMO diskette)

Special OPEN and CLOSE statements, 65

Loading, 26 Printing, 27

command),27

2040,3040,55 4040,56

Care of, 9 Inserting diskettes

2040,3040,4040,13 8050,13

BACKUP (BASIC 4.0 direct command),

COLLECT (BASIC 4.0 direct command),

COPY (BASIC 4.0 direct command), 31

COPY command, 29 CONCAT (BASIC 4.0 direct command),

DIRECTORY (BASIC 4.0 direct com-

mand, 27

DUPUCATE command, 28

Limitations due

HEADER (BASIC 4.0 direct command),

NEW

command, 24 VALIDATE command, 28 RENAME (BASIC 4.0 direct command),

RENAME command, 31

SCRATCH (BASIC 4.0 direct com-

mand),33

SCRATCH command, 32 Diskette level, 23

File level, 23

29, 30

DOS

error messages, 81

formats, 28

Disk operating system,

59,69,70,71,72,77

Disk programming, advanced, 47

Disk utility command set,

BLOCK-READ, 48, 50 BLOCK-WRITE, 48, 50

BLOCK-EXECUTE, 48, 50 BUFFER-POINTER, 48, 50 BLOCK-ALLOCATE, 48, 51 MEMORY, 51

Memory-Write, Memory-Read, 48, 52 Memory-Execute, 48, 52

USER, 48, 52

Disk zones, 59 DLOAD command, 36 DOPEN command, 39 DOS,15,18,22,25,47,59,69,70,71,

72,77

DOS

support, 22, 77

Loading DOS support, 15, 18, 77

Loading a program, Loading and running a program, Special Using DOS

Limitations, 79 Disk backup, 15, Disk drive

Care of, 9

Description, 3

Connecting

Power-on test, 12

Performance tests,

Specifications, disk drives, 5, 6, 7, 8

Unpacking, 9

Disk ID, DSA EOI signal, Error messages, 81

Description of

Requesting error messages, 81 Summary of error messages, 82

Expanded

2040 format,

8050 format, 63 Field fitting, 66 File format, program, 61

File handling, advanced, 65

File pointer, Floppy disk hookup, 11

Format

DOS

support, 79

symbols>

Front panel, 3 Back panel, 3 Interior configuration, 4

computer, 11

24, 25, 26

command, 35

view,

single sector 62

15,18,22,25,47,

48, 51

14,17,

and @, 78

18, 66

14,

DOS

error messages, 82

BAM

2040,3040,55

15,18,

Page 94

4040,56 8050,57

Directory,

2040,3040,55 4040,56 8050,57

Formatting, 24, 25

GET# HEADER (BASIC 4.0 direct command), 25 High byte, 48, 51 Hookup, floppy disk, 11 ID, 24, 25, 26 IEEE-488 interface,

Indicator lights (see LED indicator lights)

INPUT# command, 42 I/O channels, 22, 47, 71

Inserting diskettes

Initialization

Job

Key file, primary (see primary key file) LED (light emitting diode; see LED

LED indicator lights, 3, Limitations, DUPLICATE command, 28 Line feed, suppression of, 41 LOAD$ command, 26 Loading

Low byte, Magnetic fields, 9 Maintenance commands, disk, 23 MEMORY commands, 51

OPEN command, 38

Operating system, disk, 15, 18, 22, Parameters,

Parms,48 Pattern matching, 85 Performance test

command, 41

2040,3040,4040,13

8050,13

2040 and 4040,26 8050,26

queue,

indicator lights)

DOS support, 77 a program with a slash and running a program with up arrow

(t)

MEMORY-WRITE command, 51 MEMORY-READ command, 52 MEMORY-EXECUTE command, 52

59,69,70,71,72,77

3040,25

symbol, 79

48,

4,11,47

12,

18, 81

(I) symbol, 78

25,47,

4040/8050, 14 2040/3040,

POKE command, Pointer, block, 26 PRG file, 36, 61

14,

Primary key file (.KEY01), PRINT# Program file, 61 Program file format, 61 Quickload feature, Quick reference: commands, Random access

Add a record, Change a record, Create a file, Ending the program, Example, 66 Field markers, 66 Field size,

Getting directoryoflistings, Primary file names, Primary key file, 66 Record size, 66

See a record, Reading list, 4 RECORD# command, 43 Record pointer, Relative files,

4040,8050,69

Accessing, 73

Block pointers, 70

Channel restrictions, 71

Creating, 72

DOS compatability, 69

Expanding a file, 70

Format, 70

Main components,

Record size, 69

Side sectors, 69 Side tracks,

Storage capacity, 70 RENAME (BASIC 4.0 direct command),

32 RENAME command, 32 Requesting error messages, 81 Safety feature, HEADER command, 25 SAVE command, 36 SCRATCH (BASIC 4.0 direct command),

33 SCRATCH command, 33 Screen displays, actual,

19,26,37,40,44,45,77,81 Secondary address, 35, Sector, single: expanded view, 70 Sequential format, 61 Side sectors, Side track, Simplifying commands, 77 Single record access,

command, 41

Restrictions,

14,

15, 16, 17, 18,

38,42,47,

Page 95

Single sector, expanded view, 70

(I) symbol (see DOS support)

Slash Spanning, 71 Specifications

8050,6 2040/3040, 7 4040,8

Standard jump table, 53

Summary

BASIC commands, data handling, 35 Disk commands, 86 Disk maintenance commands, 23 Disk utility commands, 48 Error messages, 81

Suppression of line feeds, 41

Symbols, Tab, write protect,

DOS

support, 78

13 Tapetodisk, 45 TEST/DEMO diskettes,

command, 52

9,14,17,23

Universal wedge, 23, 77 Up

arrow

(t)

symbol (see

DOS

support) USER command, 52 User's quick reference: disk commands, 86 Utility commands, disk,

48 VALIDATE command, 28 VERIFY command, 37 Wedge Write protect tab,

(»

symbol (see

DOS

support)

Page 96

(::

commodore

Commodore Business Machines, Inc. 3330 Scott Boulevard Santa Clara, California 95051

Commodore 2040, 3040, 4040, 8050 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual