Commodore 2040 User manual

User's Manual
for
CBM 5Y4-inch
Dual
Floppy Disk
Drives
ell commodore

User's Manual
for
CBM Dual Drive
Floppys
Model 2040-Model 4040
Model 3040-Model 8050
Appropriate for use with:
Commodore Computers
• Series 2001 (CBM-PET)
•
Series 3000 CBM)
• Series 4000 PET)
• Series 8000 CBM)
Part Number 320899
October 1980
(I[ commodore
©1980 Commodore Business Machines, Inc.

Chapter 1
Chapter 2
Chapter 3
Table of Contents
Page
Introduction. ............................................. 1
General Information .................................... 2
Description ........................................... 3
Front Panel 3
Back Panel 3
Interior Configuration 4
The Diskette .................................. 5
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Care Of The 2040, 3040, 4040 and 8050 . . . . . . . . . . . . . . . . . . . . 9
Care
Of The Diskettes 9
Unpacking The Disk Drive 9
Preparing To
Use Your Disk Drive 11
Connecting The Disk Drive To The Computer 11
Performing The Power-On Test 12
Inserting The Diskette Into The 8050 13
Inserting The Diskette Into The 2040, 3040 and 4040
.. 13
The 4040 and 8050 Performance Test 14
The 2040 and 3040 Performance Test 17
Learning How To
Use Your Floppy Disk Drive 21
The Block Availability Map (BAM) 22
The Disk Operating System (DOS) ,22
Disk Maintenance Commands. ..........................
.. 23
NEW 24
HEADER (BASIC 4.0 Direct Command) . .
.. 25
Initialization (2040 and 3040) ..................
.. 25
Initialization (4040) ..........................
.. 26
Initialization (8050) ..........................
.. 26
The Directory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.. 26
LOAD$ 26
DIRECTORY (BASIC 4.0 Direct
Command). 27
Printing The
Directory. . . . . . . . . . . . . . . . .. 27
iii

IV
Chapter 4
Chapter 5
Chapter 6
VALIDATE.................................. 28
COLLECT (BASIC 4.0 Direct Command). .
.. 28
DUPLICATE 28
BACKUP (BASIC 4.0 Direct Command). . .
.. 29
COpy 29
COpy (BASIC 4.0 Direct Command) ..... .. 31
CONCAT (BASIC 4.0 Direct Command). . .
.. 31
RENAME 31
RENAME (BASIC 4.0 Direct Command) . .
.. 32
SCRATCH 32
SCRATCH (BASIC 4.0 Direct Command). .
.. 33
BASIC Commands For Data Handling 35
BASIC Commands Associated with Floppy Disk Drives .......
.. 35
SAVE and DSAVE (Writing aProgram
to aDiskette) . .. 36
LOAD and DLOAD (Reading aProgram 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)
.. ....................... .. 44
Moving aTape Program
to Disk 45
Advanced Disk Programming 47
Commodore Disk Operating System (DOS) 47
Disk Utility Command Set .............................
.. 48
BLOCK-READ................................ 49
BLOCK-WRITE. .......
.. .. .. . . .. . . .. .. .. ... .. 50
BLOCK-EXECUTE 50
BUFFER-POINTER ..........................
.. 50
BLOCK-ALLOCATE "
.. ............ .. . .. 51
MEMORy 51
MEMORY-WRITE
51
MEMORY-READ. ................... .. 52
MEMORY-EXECUTE 52
USER....................................... 52
8050 Disk Zones 59
Advanced File Handling ...................................
.. 65
Special Open and Close Statements For Direct Access ........
.. 65
Random Access Example . . . . . . . . . . . . . . . . . . . . . .
.. 66
To Create AFile .....................
.. 66
To Add A
Record. ................... .. 67
To See ARecord 68
To Change ARecord 68
Getting The Directory of Listings . . . . . . . .
.. 69

Chapter 7
Chapter 8
Chapter 9
Chapter 10
Ending The Program . . . . . . . . . . . . . . . . . .
.. 69
Relative Files 4040, 8050 . . . . . . . . . . . . . . . . . . . . . .
.. 69
Creating ARelative File
.. . . . . . . . . . . . . . . . . . . . . . .. 72
Expanding ARelative File 72
Accessing ARelative File . . . . . . . . . . . . . . . . . . . . . .
.. 73
Simplifying The
Use of Commodore Disk-Related Commands. . . . . . .. 77
Loading The
DOS Support Program . . . . . . . . . . . . . . . . . . . . . . .. 77
Using The
DOS Support Symbols: >and @ . . • • . • • . • . • . • • . • .• 78
Loading AProgram With The 1. . . . . . . . . . . . . . . . . . . . . . . . . .
.. 78
Loading And Running AProgram With
Up Arrow .. . . . . . . . . . .. 79
Special
DOS Support Information 79
Error Messages -Pattern Matching File Names -Disk Commands. . .
.. 81
Requesting Error Messages: Commodore Disk Drives. . . . . . . . .
.. 81
Summary Of
CBM Floppy Error Messages 82
Description of
DOS Error Messages 82
Pattern Matching 85
User's Quick Reference: Disk Commands. . . . . . . . . . . . . . . . . .
.. 86
Random 1.00 Program Listing 89
Index , . . . . . . . . . . . . . . .
.. 95
List of Illustrations
Figure Title
Page
1Models 2040, 3040, 4040, 8050: Rear View 5
2Floppy Disk Hookup 12
3Position For Diskette Insertion 13
4
2040,3040,4040 Format: Expanded View of ASingle Sector 62
58050 Format: Expanded View of ASingle Sector 63
List of Tables
Table Title Page
1Suggested Reading List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2Specifications: Model 8050 Dual Drive Floppy Disk 6
3Specifications: Models 2040/3040 Dual Drive Floppy
Disk. . . . . . . . . . 7
4Specifications: Model 4040 Dual Drive Floppy Disk 8
5Standard Jump Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.. 53
6Block Distribution
By Track 54
7
2040,3040 BAM Format. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 55
8
2040,3040 Directory Header. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 55
94040
BAM Format. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .. 56
10 4040 Directory Header. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 56
11 8050 Directory Header
Block. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 57
12 8050 BAM Format. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 58
v

vi
13
14
15
16
17
Directory Format. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 60
Sequential Format
61
Program File Format 61
Relative File Format 70
User's Quick Reference -Disk Commands 87

Chapter 1
INTRODUCTION
The disk-oriented Commodore Computer System was designed around the central concept
of providing you, the user, with large file-handling capabilities supported by
BASIC pro-
gramming commands and further simplified by
DOS Support command abbreviations.
Read the Table of Contents and become acquainted with the broad scope of material
covered
in this manual. It has been designed to assist you in pursuing an educational pro-
gram by utilizing the computer
as an adjunct to the learning process. That is, once the disk
drive
is properly interfaced to aCommodore Computer, YOU become as important an ele-
ment of the system
as the hardware. Your importance, however, is measured in direct rela-
tionship
to how well you understand how to effectively utilize the hardware and software.
That's why it
is best to think of your computer and disk drive as only part of asystem.
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 funda-
mental grasp of how
to operate, control, and master the system. This basic concept forms
the basis of this manual: teaching you how to gain mastery of the system so that it will
perform as desired. That
is the primary reason this manual is laid out in abuilding block
fashion: it permits you
to advance as fast as you desire.
The first chapters discuss basic hardware features and permit you, right from the start,
to
become familiar with the disk drive by doing the performance tests which comprise the first
essential "hands
on" experience. Then, by actually using your particular disk drive and
learning
to carefully follow instructions, you can gain confidence in order to proceed to
more comprehensive subjects.
By the time you begin Chapter 3-Learning How To Use Your Floppy Disk Drive-you will
have already used some portions of the
DOS Support system which is not fully described
until Chapter 7. The reason for this procedure lies within the purpose of
DOS Support:
simplifying commands.
It is actually easier to instruct anew user by using the simplified
command structure of
DOS Support than attempting to explain the entire command hier-
archy at an early stage. This concept of providing you with enough essential information
to
complete atask, astep-by-step description of the task, and meaningful examples is afeature
of this manual which will provide you with sufficient incentive to actually complete the
task.
1

2
The manner in which this manual
is laid out encourages the concept of learning by doing.
Difficult concepts and procedures have been broken down
into steps that walk the user
through examples which provide ample
opportunity to experiment later by returning to
each command description. When possible, the command format has been included with the
command description and, as an additional aid, aUser's Quick Reference has been placed in
Chapter 8for easy access if problems persist.
Error messages are also presented in Chapter 8where
they can be quickly referenced, if
needed. The Error Message discussions have been expanded
to include:
•How
to request error messages.
•Error message summary.
•Detailed error message descriptions.
For those users who have been reluctant to attempt disk programming because of the pre-
sumed degree
of difficulty, note that the entire disk command hierarchy is structured in this
manual from least difficult
to more complex:
•Commands for file manipulation and maintenance
•Commands for
data handling
•Advanced programming
•Advanced file handling
•Simplified commands
Users who have
attained some degree of programming skills may desire to begin with the
advanced subjects such as random access or relative files while others may be content with
just following
the manual's format. In either case, this manual has been laid out to provide
the user with essential information in alogical sequence. Follow the examples, attempt the
step-by-step procedures, and learn by doing.
GENERAL INFORMATION
With the purchase of your Commodore Dual Drive Floppy Disk you have greatly enhanced
the computing power of your Commodore system. To get the most out of your system you
should study your computer's user guide, and if necessary the BASIC manuals listed in
Table 1. You will benefit most if
you first read through this entire manual, taking note of
those features that relate to your particular floppy as well as those which are common to all
CBM Floppys.
The information presented in this manual is extensive and may, in some cases, present in-
formation
that is currently beyond your particular level of expertise. However, by carefully
and thoughtfully studying its
contents you will gain the confidence necessary to progres-
sively upgrade
your programming skills and expertise.
This manual presents discussions, descriptions, practices and procedures relating
to the use
and operation
of all Commodore 5-1I4-inch Dual Floppy Disk Drives.
Four models are discussed:
Model
2040 (DOS 1)
Model 3040 (DOS 1)
Model 4040 (DOS2)
Model
8050 (DOS 2.5)

The floppys are operationally compatible with the following Commodore Computers.
1. Series 2001 -16K and 32K -Operating With BASIC Version 3.0
2. Series 2001 -PET 8K -Upgraded to BASIC Version 3.0
3. Series 3000 -16K and 32K -Operating
With BASIC Version 3.0
4. Series 4000 -PET 8K, 16K, and 32K -Operating
With BASIC Version 4.0
5. Series 8000 -32K -Operating
With BASIC Version 4.0
For ease of reference, the Models 2040,
3040,4040, and 8050 Dual Drive Floppy
Disks will
be referred to in this manual as "the 2040", "the 3040", "the 4040",
and
"the 8050", respectively. All descriptions and discussions are common unless
noted otherwise.
DESCRIPTION
All CBM Floppys described in this 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.
All disk drives
discussed
in this manual conform to IEEE-488 interface requirements. Because each device
is an "intelligent" peripheral, their operation requires no space in the computer's memory.
This means you have just
as much computer memory available to you as when you do not
have the disks attached.
Front Panel
The front panel of the respective disk drive consists of an identification panel across the top;
slots
in which to insert two diskettes; and doors to close after inserting the diskettes. When
the door is closed, the diskette is clamped onto the diskette spindle hub. Also on the front
panel are three LED indicator lights. The one on the right
is called the Drive 0Active Indi-
cator, and lights when drive 0
is active. The LED on the left does the same for drive 1. On
the 8050, the LED in the middle is atwo-color power/error indicator. It is normally green,
indicating power
ON but flashes red whenever adisk error occurs. On the 2040, 3040, and
4040 the middle LED
is activated if power is applied or removed, and whenever an error
occurs.
Back Panel
The back of each disk drive contains an IEEE-488 interface connector. Near the panel's
lower edge
is the power ON/OFF switch. There is also a"slow blow" fuse, and the AC
power cord.
3

4
Table 1. Suggested Reading List
PetICBM Personal
Computer Guide.
C. S. Donahue and J. K. Enger, Osborne/McGraw-Hill, 630 Bancroft Way,
Berkeley,
CA 94710
Hands-On Basic with aPet.
H. D. Peckham, McGraw-Hill,
1979
Entering BASIC.
J. Sack and
J. Meadows, Science Research Associates, 1973
BASIC: A Computer Programming Language.
C. Pegels, Holden-Day, Inc., 1973
BASIC Programming.
J. Kemeny and T. Kurtz, Peoples
Computer Co., 1010 Doyle (P.O. Box
3100), Menlo Park, CA
94025, 1967
BASIC FOR HOME COMPUTERS.
Albrecht, Finkle
and Brown, Peoples Computer Co., 1010 Doyle (P.O. Box
3100), Menlo Park,
CA 94025, 1973
AGuided Tour of Computer Programming in BASIC.
T. Dwyer, Houghton Mifflin Co.,
1973
Programing Time Shared Computer in BASIC.
Eugene H. Barnett, Wiley-Interscience, LIC 72-175789
Programming Language #2.
Digital Equipment Corp., Maynard, MA 01754
101 BASIC Computer Games.
Software Distribution Center, Digital
Equipment Corp., Maynard, MA 01754
What do To After You Hit Return.
Peoples Computer Co., 1010 Doyle (P.O. Box 3100), Menlo Park, CA 94025
Basic BASIC.
James
S. Coan, Hayden Book Co., Rochelle Park, NJ
WORKBOOKS
1-5.
T.I.S., P.O. Box 921, Los Alamos, NM 87544
Programming the 6502.
R. Zaks, Sybex, 1978
24 Tested, Ready-to-Run Game Programs in Basic.
K. Tracton, Tab Books, 1978
Some Basic Programs.
M. Borchers and R. Poole, Osborne &Assoc. Inc., 1978
Basic Programming for Business.
I. H. Forkner, Prentice-Hall, 1977
The Channel Data Book.
B. Lewis, 5960 Mandarin Ave., Goleta, CA 93017,1978
PET and the IEEE 488 Bus (GPIP).
Osborne/McGraw-Hill, 630 Bancroft Way, Berkeley, CA 94710
Interior Configuration
The interior of your floppy contains two disk drives. All the logic for the disk drive is con-
tained within
the unit. The mechanical devices are, for the most part, located beneath the
disk spindles.