Ive been writing a rom and reading reference for a while.
Im pritty used to the VDP now, but i cant seem get the V and H interrupts working.
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video_setup:
lea ($C00000).l,a0 ;// set a0 to vdata
lea ($C00004).l,a1 ;// set a1 to vctrl
move.w #$8014,(a1) ;// : mode set #1: [0][0][0][IE1][0][1][M3][0]
move.w #$8164,(a1) ;// : mode set #2: [0][DIS][IE0][M1][M2][1][0][0]
....
The program loop moves a sprite from left to right by updating the attribute table.
At the start of the loop i waste some processes.
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scene_ac:
move.w #$1000,d0 ;// $1000 to d2
scene_ac_aa:
dbf d0,scene_ac_aa
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bra scene_ac
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Horizontal:
nop
nop
nop
move.w #$8124,(a1)
rte
Vertical:
nop
nop
nop
move.w #$8124,(a1)
rte
In the gen techs, it states the H interrupt may cancel the V interrupt, that had 2 solutions, 1 of them confused the hell outta of me.
Know any reasons why this may happen?.. Tanks in advance :L