************************************************************* * * * EACH OF THE FOLLOWING TABLES DESCRIBES A DISKETTE WITH * * THE SPECIFIED CHARACTERISTICS. * * * ************************************************************* ************************************************************* * * * THE FOLLOWING DPB DEFINES A DISKETTE FOR 128 BYTE * * SECTORS, SINGLE DENSITY, AND SINGLE SIDED. * * * ************************************************************* DPB128S DW 26 ;SPT CP/M SECTORS/TRACK DB 3 ;BSH BLOCK SHIFT FACTOR DB 7 ;BLM BLOCK MASK DB 0 ;EXM EXTENT MASK DW 242 ;DSM DISK SPACE MAXIMUM DW 63 ;DRM DIRECTORY MAXIMUM DB 0C0H ;AL0 INITIAL ALLOTARION DB 0 ;AL1 VECTORS DW 16 ;CKS DIRECTORY CHECK SIZE DW 2 ;OFF TRACK OFFSET DB 00 ;PSH PHYSICAL REC SHIFT FACT DB 00 ;PHM PHYSICAL RECORD MASK ;NEXT BYTE USED BY THE BIOS DB 1H ;16*((#CPM SECTORS/PHYSICAL ;SECTOR) -1) + LOG2(#BYTES ;PER SECTOR/128) + 1 + 8 IF ;DOUBLE SIDED. ************************************************************* * * * THE FOLLOWING DPB DEFINES A DISKETTE FOR 256 BYTE * * SECTORS, DOUBLE DENSITY, AND SINGLE SIDED. * * * ************************************************************* DPB256S DW 52 ;CP/M SECTORS/TRACK DB 4 ;BSH DB 15 ;BLM DB 0 ;EXM DW 242 ;DSM DW 127 ;DRM DB 0C0H ;AL0 DB 0 ;AL1 DW 32 ;CKS DW 2 ;OFF DB 00 ;PSH DB 00 ;PHM ; DB 12H ;16*((#CPM SECTORS/PHYSICAL ;SECTOR) -1) + LOG2(#BYTES ;PER SECTOR/128) + 1 + 8 ;IF DOUBLE SIDED. ************************************************************* * * * THE FOLLOWING DPB DEFINES A DISKETTE AS 512 BYTE SECTORS, * * DOUBLE DENSITY, AND SINGLE SIDED. * * * ************************************************************* DPB512S DW 60 ;CP/M SECTORS/TRACK DB 4 ;BSH DB 15 ;BLM DB 0 ;EXM DW 280 ;DSM DW 127 ;DRM DB 0C0H ;AL0 DB 0 ;AL1 DW 32 ;CKS DW 2 ;OFF DB 00 ;PSH DB 00 ;PHM ; DB 33H ;16*((#CPM SECTORS/PHYSICAL ;SECTOR) -1) + LOG2(#BYTES ;PER SECTOR/128) + 1 + 8 ;IF DOUBLE SIDED. ************************************************************* * * * THE FOLLOWING DPB DEFINES A DISKETTE AS 1024 BYTE SECTORS,* * DOUBLE DENSITY, AND SINGLE SIDED. * * * ************************************************************* DP1024S DW 64 ;CP/M SECTORS/TRACK DB 4 ;BSH DB 15 ;BLM DB 0 ;EXM DW 299 ;DSM DW 127 ;DRM DB 0C0H ;AL0 DB 0 ;AL1 DW 32 ;CKS DW 2 ;OFF DB 00 ;PSH DB 00 ;PHM ; DB 74H ;16*((#CPM SECTORS/PHYSICAL ;SECTOR) -1) + LOG2(#BYTES ;PER SECTOR/128) + 1 + ;8 IF DOUBLE SIDED. ************************************************************* * * * THE FOLLOWING DPB DEFINES A DISKETTE FOR 128 BYTE SECTORS,* * SINGLE DENSITY, AND DOUBLE SIDED. * * * ************************************************************* DPB128D DW 52 ;CP/M SECTORS/TRACK DB 4 ;BSH DB 15 ;BLM DB 1 ;EXM DW 242 ;DSM DW 127 ;DRM DB 0C0H ;AL0 DB 0 ;AL1 DW 32 ;CKS DW 2 ;OFF DB 00 ;PSH DB 00 ;PHM ; DB 9H ************************************************************* * * * THE FOLLOWING DPB DEFINES A DISKETTE AS 256 BYTE SECTORS, * * DOUBLE DENSITY, AND DOUBLE SIDED. * * * ************************************************************* DPB256D DW 104 ;CP/M SECTORS/TRACK DB 4 ;BSH DB 15 ;BLM DB 0 ;EXM DW 486 ;DSM DW 255 ;DRM DB 0F0H ;AL0 DB 0 ;AL1 DW 64 ;CKS DW 2 ;OFF DB 00 ;PSH DB 00 ;PHM ; DB 1AH ************************************************************* * * * THE FOLLOWING DPB DEFINES A DISKETTE AS 512 BYTE SECTORS, * * DOUBLE DENSITY, AND DOUBLE SIDED. * * * ************************************************************* DPB512D DW 120 ;CP/M SECTORS/TRACK DB 4 ;BSH DB 15 ;BLM DB 0 ;EXM DW 561 ;DSM DW 255 ;DRM DB 0F0H ;AL0 DB 0 ;AL1 DW 64 ;CKS DW 2 ;OFF DB 00 ;PSH DB 00 ;PHM ; DB 3BH ************************************************************* * * * THE FOLLOWING DPB DEFINES A DISKETTE AS 1024 BYTE SECTORS,* * DOUBLE DENSITY, AND DOUBLE SIDED. * * * ************************************************************* DP1024D DW 128 ;CP/M SECTORS/TRACK DB 4 ;BSH DB 15 ;BLM DB 0 ;EXM DW 599 ;DSM DW 255 ;DRM DB 0F0H ;AL0 DB 0 ;AL1 DW 64 ;CKS DW 2 ;OFF DB 00 ;PSH DB 00 ;PHM ; DB 7CH