The new anatomy of the 1541 disk drive : a complete guide to using the Commodore disk drive

Chapter 1: Programming the VIC-1541                      1
1.1 Getting started                                     1
    1.1.1 After Unpacking                               1
    1.1.2 The Disk Operating System                     4
    1.1.3 The TEST/DEMO Diskette                        4
    1.1.4 Fomatting New Diskettes                       5
    1.1.5 Some Facts about a 1541 Diskette              5
    1.1.6 Fundamentals of Disk Techniques               6

1.2 Program Management on Diskette                       9
    1.2.1 Save - Storing BASIC Programs                  9
    1.2.2 LOAD - Loading BASIC Programs                 10
    1.2.3 VERIFY - Checking Stored Programs             11
    1.2.4 SAVE \"@: ... \" - Replacing Programs           12
    1.2.5 Loading Machine Language Programs             13
    1.2.6 Storing Machine Language Programs             15

1.3 Disk System Commands                                19
    1.3.1 Transmitting Commands to the Disk Drive       19
    1.3.2 NEW - Formatting Diskettes                    20
    1.3.3 Reading the Error Channel                     22
    1.3.4 LOAD\"$\",8 - Loading the Directory             24
    1.3.5 SCRATCH - Deleting Files                      26
    1.3.6 RENAME - Renaming Files                       28
    1.3.7 COPY - Copying Files                          31
    1.3.8 INITIALIZE - Initializing the Diskette        32
    1.3.9 VALIDATE - \"Cleaning Up\" the Diskette         33
    1.3.10 ? * - The Wildcards                          34

1.4 Sequential Data Storage                             37
    1.4.1 The Principle                                 37
    1.4.2 Opening a Sequential Data File                39
    1.4.3 Transferring Data Between Disk and Computer   42
    1.4.4 Adding Data to Sequential Files               46
    1.4.5 Closing a Sequential File                     47
    1.4.6 Redirecting the Screen Output                 48
     1.4.7  Sequential Files as Tables in the Computer       50
     1.4.8  Searching Tables                                 53
     1.4.9  Simple Sorting of Tables                         57
     1.4.10 MAILING LIST MANAGEMENT with Sequential
                Data Storage                                 60
     1.4.11 Uses for Sequential Storage                      70
 1.5 Relative Data Storage                                   71
     1.5.1 The Principle                                     71
     1.5.2 The Advantage over Sequential Storage             72
     1.5.3 Opening a Relative File                           73
     1.5.4 Preparing Data for Relative Storage               76
     1.5.5 Transferring Data                                 78
     1.5.6 Closing a Relative File                           83
     1.5.7 Searching Records with the Binary Method          83
     1.5.8 Searching Records with a Separate Index File      87
     1.5.9 Changing Records                                  90
     1.5.10 Expanding a Relative File                        92
     1.5.11 Home Accounting with Relative Data Storage       93
1.6 Additional File Structures                              105
    1.6.1 Direct Addressing                                 105
    1.6.2 Indirect Addressing                               107

1. 7 Disk Error Messages and their Causes                   109

1.8 Overview of Commands with a Comparison of BASIC 2.0 _
         BASIC 4.0 - BASIC 7.0 - DOS 5.1                    115
    1.8.1 BASIC 4.0 - BASIC 7.0 Commands                    116
    1.8.2 BASIC 7.0 commands                                122

Chapter 2: Advanced Programming                             125

2.1 Direct Access of any Block of the Diskette              125

2.2 The Direct Access Commands                              129
    2.2.1 The Block-Read Command                            129
    2.2.2 The Block-Pointer Command                         130
    2.2.3 The Block-Write Command                           131
    2.2.4 The Block-Allocate Command                        133
    2.2.5   The Block-Free Command                           134
    2.2.6   The Block-Execute Command                        135

2.3 Uses of Direct Access                                    137

2.4 Accessing the DOS - The Memory Commands                  139
    2.4.1 The Memory-Read Command                            139
    2.4.2 The Memory-Write Command                           141
    2.4.3 The Memory-Execute Command                         142
    2.4.4 The User Commands                                  143
    2.4.5 Additional Possibilities for the User Commands     145


Chapter 3: Technical Information                             147

3.1 TheConstructionoftheVIC-l541                             147
    3.1.1 Block Diagram of the Disk Drive                    147
    3.1.2 DOS Memory Map - ROM, RAM, I/O                     148
    3.1.3 Layout of the I/O Ports (VIA 6522)                 149
    3.1.4 The Layout of the Important Memory Locations       150

3.2 Operation of the DOS - An Overview                       155
    3.2.1 The Disk Controller Routines                       156

3.3 The Structure of the VIC-1541 Diskette                   159
    3.3.1 The BAM of the VIC-1541                            159
    3.3.2 The Directory                                      161
    3.3.3 The Directory Format                               164
    3.3.4 The Diskette Recording Process                     170
3.4 The Organization of Relative Files                       175

3.5 DOS 2.6 ROM Listings                                     181

Chapter 4: Programs and Tips for Using the 1541 Disk Drive   415

4.1 Utility Programs                                         415
    4.1.1 Displaying all File Parameters                     415
    4.1.2 Scratch-protect Files - File Protect               422
    4.1.3 Backup Program - Copying a Diskette                429
    4.1.4   Copying Individual Files to another Diskette       432
    4.1.5   Reading the Directory from within a Program        434
    4.1.6   Searching for \"Hidden\" Files                       435
    4.1.7   Changing the Disk Name and the ID                  438
    4.1.8   Software Write Protect                             441
    4.1.9   Invisible Directory                                442
4.2 The Utility Programs on the TESTIDEMO Disk                 445
    4.2.1 DOS 5.1                                              445
    4.2.2 COPY/ALL                                             446
    4.2.3 DISK ADDR CHANGE                                     447
    4.2.4 DIR                                                  448
    4.2.5 VIEW BAM                                             448
    4.2.6 CHECK DISK                                           448
    4.2. 7 DISPLAY T &S                                        449
    4.2.8 PERFORMANCE TEST                                     449

4.3 BASIC Extensions and Programs for the 1541                 451
    4.3.1 Input Strings of Desired Length from the Disk        451
    4.3.2 Easy Preparation of Data Records                     456
    4.3.3 Spooling - Printing Directly from the Disk           465
4.4 Overlay Technique and Chaining Machine Language Programs   469
4.5 Merge - Appending BASIC Programs                           473
4.6 Disk Monitor for the Commodore 64 and VIC 20               475

4.7 Using \"WEDGE\" Commands from BASIC Programs                 497


Chapter 5: The Larger CBM Disks                                499

5.1 IEEE-Bus and Serial Bus                                    499

5.2 Overview of the \"large\" CBM Disk Drives                    503