Commodore 1541-II Guida Utente

COMMODORE TI LtTI El D '" DISK DRIVE users guide

TROUBLESHOOTING GUIDE Symptom Prograrlls won't load, and computer says "Dl;lVICE NOT PRESENT ERROR ." Programs won't load, but com

WHAT IS A DISKETTE? CHAYfER2 DISKETIES Before we actually begin using the drive, let's take a moment to look at the Test/Demo diske

SAFJ;TY RULES FOR REMOVING DISKETIES Always remove diskettes before turning a drive off or. on. If a diskette were in place and the door closed at

number of the 1541, normally 8; the drive number, always 0 on the 1541; any desired name for the diskette, up to 16 characters in length, fol

WHAT IS A DIRECTORY? CHAPTER3 DIRECTORIES One of the primary advantages of a disk drive is that it can, with nearly equal ease and speed, access

The rest of the directory contains one line per program or file, each line supplying three pieces of information about its subject. At the left end

LOAD"$0:* = S" ,8 will load a directory of all sequential files, while the Basic 3.5 command: DIRECTORY," A*= R'' will di

PART TWO: GUIDE TO ADVANCED OPERATION AND PROGRAMMING COMMAND CHANNEL CHAPTER4 COMMANDS Commodore disk drives expect to receive many of their inst

FORMAT FOR SENDING DISK COMMANDS OPEN 15,device #,15,commandS or Print# 15 ,command$ Examples: OPEN 15,8,15,"VO" or PRINT#l5,"VO"

HOUSEKEEPING HINTS Hint #1: It is best to open file IS once at the very start of a program, and only close it a1 the end of the program, after all

COMMODORE 1541-II DISK DRIVE USER'S GUIDE This manual contains copyrighted and proprietary information. No part of this publication may be

SA VE WITH" REPLACE OPTION If a file already exists, it can't be saved again because the disk only allows one copy of any given file name

FORMAT FOR THE SCRATCH COMMAND: PRINT# 15, "SCRA TCHO: pattern" or abbreviate it as: PRINT# 15, ''SO:pattern'' '&ap

More about Splats One other warning-never scratch a splat file. These are files that show up in a directory listing with an asterisk (*)ju

RENAMING AND SCRA TCIDNG TROUBLESOME FILES (ADVANCED USERS) Eventually, you may run across a file which has a crazy filename, such as a comma by

NOTE: Dual drives make fuller use of this command, copying programs from one diskette to another in a single disk unit. To do that on the 1541,

files , with loss of all their contents when other files are added. Unless specifically instructed otherwise, never collect a diskette conta

CHAPTERS SEQUENTIAL DATA FILES THE CONCEPT OF FILES A file on a diskette is just like a file cabinet in your office-an organized place to put things.

"channel #" is a secondary address, giving further instructions to the selected device about how further commands are to be obeyed.

EXAMPLE: If you are writing a grading program, it wou.ld be convenient to simply tack on each student's new grades to the end o( their existing g

However, if you need to combine them, here is a safe way to do it: 400 PRINT#5,NAME$;CHR$(13);STREET$;CHR$(13);CITY$ CHR$(13) is the carriage return

The information in this manual has been reviewed and is believed to be entirely reliable. No responsibility, however, is assumed for inaccuracies

but many programs cheat on safety a bit anel UM; 800 INPUT#5,NAME$,STREET$,CITY$ 810 GOSUB 59990:REM CHECK FOR DISK ERRORS This is done primarily when

READING FlLE DATA: USING GET# The Get# statement retrieves data from the disk drive, one character at a time. Like the similar keyboard Get statem

DEMONSTRATION OF SEQUENTIAL FILES Use the following program for your first experiments with sequential files . Comments have been added to h

desired person out of a thousand in under 15 seconds, a feat no sequential file prograrn could match. FILE LIMITS . One of the nicest aspects of r

FORMAT FOR THE RECORD# COMMAND: PRINT#l5, "P" +CHR$ (channel #+96) + CHR$ (<record #)+CHR$ (>record #) + CHR$ (offset) where "c

1410 OPEN 1,8,2, "O:"+FI$+" ,L,"+CHR$(RL) 1420 GOSUB 59990 1430 RH= INT(NR/256) 1440 RL = NR-256*RH 1450 PRINT#l5, "P"

between maximum field length and average field length. A program that uses variable record lengths must calculate the total length of each r

3030 GOSUB 59990 3040 INPUT# l ,NA$,SA$,CS$,ZP$ 3050 GOSUB 59990 3060PRINT#15, "P" + CHR$(96 + 3) + CHR$(RL) + CHR$(RH) Check for disk error

channel is opened much like other files, except that the pound sign (#), optionaJiy 8'{AMPLE: followed by a memory buffer number, is u

EXAMPLES: To restore track 18, sector I of the directory from the disk buffer filled by the Block Read example on page 82, we can use PRINT# 15, "

PART TWO: GUIDE TO ADVANCED OPERATION AND PROGRAMMING Chapter 4: Commands •.•••••••••.•..•..••••••••••••••.•••.••••••••••••• 25 Command Channel ••...

pointer to the first file type byte (see Appendix C for details of directory organization), locking it by setting bit 6 and rewriting it. 110 OP

EXAMPLE: To free the sector in which we wrote our name in the Block Write example, and allocated in the first Block-Allocate example, we could

Other Resources: More detailed information about Commodore disk drives can be found in these books: Inside Commodore DOS, by lmmers & Neufeld (Da

FORMAT FOR THE MEMORY-WRITE COMMAND: PRINT# 15,' 'M-W' 'CHR$( <address)CHR$(>address)CHR$ (# of bytes)CHR$(data byte(s)) whe

ALTERNATE FORMATS: PRINT#l5,"B-E:";channel #;drive #;track #;sector# PRINT#l5,"B-E:channel #,drive #,track #,sector#" EXAMPLES: As

CHAPTER9 MACHINE LANGUAGE PROGRAMS Here is a list of disk-related Kemal ROM subroutines and a practical example of their use in a program which rea

STEPS TO CHANGE THE DEVICE NUMBER USING THE SWITCH 1. Tum off the disk drive. 2. Refer to the following chart to set the DIP SW at the back

24: 25: 26: 27: 28: 29: 30: 31: 32: 33: 34: READ ERROR (byte decoding error) The data or header has been read into disk memory, but a hardware error h

66: ILLEGAL TRACK AND SECTOR The DOS has attempted to access a track or sector which does not exist. May indicate a faulty link pointer

1541 BLOCK DISTRIBUTION BY TRACK Track number Range of Sectors Total # of Sectors I to 17 18 to 24 25 to 30 31to35 BYTE CONTENTS 0,1 18,01 2 65 3 0

INTRODUCTION The 1541 disk drive greatly increases the speed , storage capacity, flexibility and reliabil-ity of your Commodore computer. As you us

1541 RELATIVE FILE FORMAT BYTE DEFINITION DATA BLOCK 0, 1 Track and sector of next data block. 2-255 254 bytes of data. Empty records contain $FF (all

APPENDIX D: DISK COMMAND QUICK REFERENCE CHART General Format: OPEN 15,8,15:PRINT#15,command:CLOSE 15 (Basic 2) HOUSEKEEPING COMMANDS BASIC2 NEW COPY

SEQ.FILE.DEMO AND REL.FILE.DEMO These two files are included as programming examples or guidelines when writing your own programs. They also illustr

Commodore Business Machines, Inc. 1200 Wilson Drive • West Chester, PA 19380 Commodore Business Machines, Ltd. 3470 Pharmacy Avenue• Agincourt, Ontari

Another key advantage of the Commodore 1541 over disk drives for other computers is its dynamic allocation of disk space. Many other disk drives

SPECIFICATIONS OF THE 1541 DISK DRIVE STORAGE Total formatted capacity Maximum Sequential file size Maximum Relative file size Records per file Fil~s

EMPTY THE DRIVE First, it is very important to be sure nothing is inside the disk drive . If you tum the power off or oil with a diskette_ in

Commodore Personal Computer Single Fig 3.A Floppy Disc Hookup Personal Computer Twin Fig 3.8 Floppy Disc Hookup Power supply AC Serial Cable Power su