iS-DOS disk format

Let your enemies, Ivan, die without sons! Wed 1 Sep 1999 at 04:52, Ivan Mak ═> All: IM> Does anyone have complete information on the is-dos disk format? IM> This refers to both physical and logical formats. ────[ The file app_01 .t begins here ]─────────────────────── ┌─────────────────── ────────────────────┐ │APPENDIX 1. Structure of the descriptor │ │ device (disk) │ │ │ │0th BLOCK: (0th sector of 0th track) │ ├─────────────────── ────────────────────┤ │small-long-comments │ │yet-on │ │nie │ ├──┬──┬───────────── ────────────────────┤ │ 0│ 2│Reserve │ │ 2│ 8│Device name │ │10│ 3│iS-DOS sign: "DSK" │ │13│ 5│Reserve │ │18│ 2│Device size │ │ │ │(in blocks of 256 bytes) │ │20│ 2│Number of the 0th block of the main catalog-│ │ │ │ha │ │22│ 1│Number of tracks on device │ │23│ 1│Disk type. Bits(0/1): │ │ │ │ 0 - 40/80 tracks │ │ │ │ 1 - 1/2 sides │ │24│ 1│Sector size: │ │ │ │1/2/4: 256/512/1024 bytes │ │25│ 1│Number of sectors on the track ││26│ 1│Reserve │ │27│ 1│Checksum of 32 bytes │ │ │ │descriptor ????_dos.sys │ │28│ 2│Reserve │ │30│ 2│Date │ │32│32│Descriptor ????_dos.sys │ │64│16│Sector number table │ │ │ │on the path │ ├──┴──┴───────────── ────────────────────┤ │ 1st BLOCK: Device bitmap.│ │ 1 bit/block: 0-free/1-busy│ └─────────────────── ────────────────────┘ ????_dos.sys descriptor at offset 32 is placed in the 0th block by the con.com program and read by the boot.sys loader. . ────[The file app_01 .t ends here]──────────────────────── ────[ The file app_09 .t begins here ]─────────────────────── ┌──────────────────────────── ────────────────────────────┐ │ APPENDIX 9. Resident file service vector │ │ / bkfcb(#35) DUD.SYS / │ │ │ │ offset name length comment │ │ education │ │ │ │ -8 DSIZE 2 Open device size in blocks │ │ -6 BMSIZ 2 Size of the bitmap in bytes (see APPENDICES │ │ -4 FCBA 2 User file descriptor address ││ -2 1 Temporary file number │ │ -1 FNUMB 1 File number (#FF if the file is not open) │ │ │ │ 0 32 Descriptor of the current (open) file: │ │ 0 FNAME 8 Name │ │ 8 FTYPE 3 Type │ │ 11 FSTAT 1 File status register. Bits (0/1): │ │ 0 - deleted/exists │ │ 2 - read protected(1) │ │ 3 - write protected(1) │ │ 4 - visible/hidden file │ │ 5 - file/directory (root file) │ │ 6 - segmented/continuous │ │ 7 - protected from deletion(1) │ │ │ │ 12 FLSA 2 Default Load Address │ │ 14 FLENG 3 Length │ │ 17 FSDBN 2 Segment descriptor block number │ │ (For a continuous file - number zero │ │ file block) │ │ 19 WRKST 1 "Special" │ │ 20 6 Reserve │ │ 26 FSUM 2 File checksum ││ 28 FTIME 2 Time │ │ 30 FDATE 2 Date │ │ │ │ 32 23 Descriptor of the current (open) catalog │ │ (internal) │ │ 32/0 CATLG 8 Current directory name │ │ 40/8 3 spaces (directory type) │ │ 43/11 1 CSR catalog │ │ 44/12 CDLSA 2 CBBN of the parent catalog │ │ 46/14 *CSIZE 2 Directory size in bytes │ │ 48/16 *LEVEL 1 Subdirectory nesting level │ │ 49/17 CSDBN 2 Segment descriptor block number │ │ 51/19 CBBN 2 Number of the 0th catalog block │ │ 53/21 *NFILE 1 Total number of files (including itself │ │ directory and remote) │ │ 54/22 *NEFIL 1 Number of files without directory and deleted │ │ │ │ 55 1 │ │ │ │* - unused variables in the external descriptor │ │ catalogue. │ └──────────────────────────── ────────────────────────────┘ . ────[The file app_09 .t ends here]──────────────────────── [ WBR, Oleg. ] [ 18:41 1 September XXXIV A.S. ]