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;---------------------------Module-Header------------------------------;
; Module Name: vgaregs.asm
;
; Copyright (c) 1992 Microsoft Corporation
;-----------------------------------------------------------------------;
;-----------------------------------------------------------------------;
; VOID vInitRegs(void)
;
; Sets the VGA's data control registers to their default states.
;
;-----------------------------------------------------------------------;
.386
.model small,c
assume cs:FLAT,ds:FLAT,es:FLAT,ss:FLAT
assume fs:nothing,gs:nothing
.xlist
include stdcall.inc ;calling convention cmacros
include i386\strucs.inc
include i386\driver.inc
include i386\egavga.inc
.list
.code
cProc vInitRegs,4,< \
uses esi edi ebx, \
ppdev: ptr PDEV >
mov esi,ppdev
; Initialize sequencer to its defaults (all planes enabled, index
; pointing to Map Mask).
mov dx,VGA_BASE + SEQ_ADDR
mov ax,(MM_ALL shl 8) + SEQ_MAP_MASK
out dx,ax
; Initialize graphics controller to its defaults (set/reset disabled for
; all planes, no rotation & ALU function == replace, write mode 0 & read
; mode 0, color compare ignoring all planes (read mode 1 reads always
; return 0ffh, handy for ANDing), and the bit mask == 0ffh, gating all
; bytes from the CPU.
mov dl,GRAF_ADDR
mov ax,(0 shl 8) + GRAF_ENAB_SR
out dx,ax
mov ax,(DR_SET shl 8) + GRAF_DATA_ROT
out dx,ax
; Default to read mode 0, write mode 0:
mov edx,VGA_BASE + GRAF_ADDR
mov ah,byte ptr [esi].pdev_ulrm0_wmX[0]
mov al,GRAF_MODE
out dx,ax ;write mode 0, read mode 0
mov ax,(0 shl 8) + GRAF_CDC
out dx,ax
mov ax,(0FFh shl 8) + GRAF_BIT_MASK
out dx,ax
cRet vInitRegs
endProc vInitRegs
end