Category : Assembly Language Source Code
Archive   : DRIVEKIT.ZIP
Filename : REQHDR.MAC

 
Output of file : REQHDR.MAC contained in archive : DRIVEKIT.ZIP

;
;
; static request header
LNG EQU 0 ;BYTE: first byte is length of header
UNIT EQU 1 ;BYTE: unit number for block devices
CMD EQU 2 ;BYTE: command code for request
STAT EQU 3 ;WORD: status
DOS_Q EQU 5 ;DWORD: DOS queue
DEV_Q EQU 9 ;DWORD: device queue
;
; init header
UNITS EQU 13 ;BYTE: number of units
BRKOFF EQU 14 ;DWORD: ending address for resident code
BRKSEG EQU 16 ;
BPB EQU 18 ;DWORD: ptr to BPB array on exit (block devices only)
PARMS EQU 18 ;DWORD: ptr to string following "device=" cmd
;
; non destructive read - no wait
PRECHAR EQU 13 ;BYTE: one look ahead character
;
; input, output, IOCTL in, IOCTL out
MEDIA EQU 13 ;BYTE: media descriptor byte
BUF EQU 14 ;DWORD: buffer address
CNT EQU 18 ;WORD: byte/sector count
START EQU 20 ;WORD: starting sector number
;
; status word bit definitions (most significant byte)
;
REQDON EQU 01H ;request complete
BUSY EQU 02H ;device busy
ERROR EQU 80H ;error encountered
;
; status word error codes (least significant byte)
;
NOTRDY EQU 02H ;device not ready
UNKCMD EQU 03H ;unknown command
NOPAPER EQU 09H ;printer out of paper
WRFLT EQU 0AH ;write fault
RDFLT EQU 0BH ;read fault
FAIL EQU 0CH ;general failure