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PAGE 64, 132
TITLE Start up code for Turbo-C based Device Driver -- R.D.Allen, 9/4/87
; Copyright 1987, 1988 PARS Service Partnership

;Declare Segments & Groups. Define Device Driver Header
DGROUP	GROUP	_TEXT, _DATA, _CVTSEG, _SCNSEG, _BSS, _TAIL

ASSUME	CS:_TEXT, DS:NOTHING
_TEXT	SEGMENT BYTE PUBLIC 'CODE'	; All code goes in this segment

	PUBLIC	_header
	PUBLIC	DGROUP@
	PUBLIC	_abort
	PUBLIC	_setDGROUP

	EXTRN	_strategy:NEAR
	EXTRN	_dosio:NEAR

; ************************
; DEVICE HEADER: Must be first thing in the binary file. Always!
; ************************

_header	DW	-1						; Chain Pointer -1, only device in driver
		DW	-1
		DW	1100100000000000b		; IOCTL word, simple character device
		DW	DGROUP:_strategy
		DW	DGROUP:_dosio
		DB	"COMX    "				; Name of driver is COMX

DGROUP@			dw ?				; Turbo-C library requires this set to DS

_setDGROUP:
		MOV		CS:DGROUP@, DS		; TINY model library wants this 
									; Called during (df_) INIT. Falls into ret

_abort:	RET							; Hope this is never called!

_TEXT	ENDS
_DATA	SEGMENT BYTE PUBLIC 'DATA'	; Main data segment for driver
_DATA	ENDS
									; Additional segments desired by the
									; compilier.
_CVTSEG SEGMENT WORD PUBLIC 'DATA'
	PUBLIC	__RealCvtVector
__RealCvtVector	dw ?
_CVTSEG ENDS

_SCNSEG SEGMENT WORD PUBLIC 'DATA'
_SCNSEG ENDS

_BSS	SEGMENT WORD PUBLIC 'BSS'
_BSS	ENDS

_TAIL	SEGMENT WORD PUBLIC 'TAIL'	; Data area for initialization code
_TAIL	ENDS						; All can be thrown away

		END