Misc/abrash-black-book
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This commit is contained in:
James Gregory 2013-12-30 18:34:31 +11:00
commit 18011c595a
352 changed files with 6040 additions and 6040 deletions
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18
32-02.md
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@ -22,10 +22,10 @@
READ_MAP equ 4 ;Read Map register index in GC
SCREEN_WIDTH equ 360 ;# of pixels across screen
WORD_OUTS_OK equ 1 ;set to 0 to assemble for
; computers that can’t handle
; computers that can't handle
; word outs to indexed VGA registers
;
_DATAsegmentpublic byte ‘DATA’
_DATAsegmentpublic byte ‘DATA'
;
; 360x480 256-color mode CRT Controller register settings.
; (Courtesy of John Bridges.)
@ -65,7 +65,7 @@
endif
endm
;
_TEXTsegment byte public ‘CODE’
_TEXTsegment byte public ‘CODE'
assumecs:_TEXT, ds:_DATA
;
; Sets up 360x480 256-color mode.
@ -136,7 +136,7 @@
;
public _Draw360x480Dot
_Draw360x480Dotprocnear
push bp ;preserve caller’s BP
push bp ;preserve caller's BP
mov bp,sp ;point to stack frame
push si ;preserve C register vars
push di
@ -150,7 +150,7 @@
mov di,[bp+DrawX] ;get the X coordinate
shr di,1 ;there are 4 pixels at each address
shr di,1 ; so divide the X coordinate by 4
add di,ax ;point to the pixel’s address
add di,ax ;point to the pixel's address
mov cl,byte ptr [bp+DrawX] ;get the X coordinate again
and cl,3 ;get the plane # of the pixel
mov ah,1
@ -164,7 +164,7 @@
stosb ;draw the pixel
pop di ;restore C register vars
pop si
pop bp ;restore caller’s BP
pop bp ;restore caller's BP
ret
_Draw360x480Dotendp
;
@ -184,7 +184,7 @@
;
public _Read360x480Dot
_Read360x480Dotprocnear
push bp ;preserve caller’s BP
push bp ;preserve caller's BP
mov bp,sp ;point to stack frame
push si ;preserve C register vars
push di
@ -198,7 +198,7 @@
mov si,[bp+DrawX] ;get the X coordinate
shr si,1 ;there are 4 pixels at each address
shr si,1 ; so divide the X coordinate by 4
add si,ax ;point to the pixel’s address
add si,ax ;point to the pixel's address
mov ah,byte ptr [bp+DrawX] ;get the X coordinate again
and ah,3
;get the plane # of the pixel
@ -210,7 +210,7 @@
sub ah,ah ;make the return value a word for C
pop di ;restore C register vars
pop si
pop bp ;restore caller’s BP
pop bp ;restore caller's BP
ret
_Read360x480Dot endp
_TEX Tends