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intin equ 8 ; setup some constants
ptsin equ 12
colbit0 equ 24
colbit1 equ 26
colbit2 equ 28
colbit3 equ 30
lstlin equ 32
lnmask equ 34
wmode equ 36
x1 equ 38
y1 equ 40
x2 equ 42
y2 equ 44
init equ $a000
setpix equ $a001
getpix equ $a002
drwlin equ $a003
start:
jsr initialize
dc.w init ; call line a init
move.w #1,colbit0(a0) ; setup arguments to draw line
move.w #1,colbit1(a0)
move.w #1,colbit2(a0)
move.w #1,colbit3(a0)
move.w #0,lstlin(a0)
move.w #$ffff,lnmask(a0)
move.w #0,wmode(a0)
move.w #0,x1(a0)
move.w #0,y1(a0)
move.w #100,x2(a0)
move.w #100,y2(a0)
dc.w drwlin ;call line a draw line
move.w #7,-(a7)
trap #1 ;wait keypress
addq.l #2,a7
jsr restore
clr.l -(a7) ;call gemdos
trap #1
initialize: ; go into super user mode
clr.l -(a7)
move.w #32,-(a7)
trap #1
addq.l #6,a7
move.l d0,oldstack
rts
restore: ; go back into user mode
move.l oldstack,-(a7)
move.w #32,-(a7)
trap #1
addq.l #6,a7
rts
oldstack dc.l 0
; comment at eof
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