base:rasterbars_4_source
Rasterbars 4 source
$D020-$D021 and $D022 example, can be modified for other effects too.
;64tass format ;taken from s451-1 intro, stabilized and NTSC support added ;without delay table-values * = $1000 sei loop lda #$42 ;must start on a badline. ($x2 or $xA) - cmp $d012 bne - cmp ($00),y ldx #$00 ldy #$01 nop ;NTSC : change this byte to $d1, becomes cmp ($ea),y br1 nop cmp ($00,x) br2 lda #$00 ;NTSC : change this to lda $00,x cmp ($00,x) inx lda col1,x sta val1+1 lda col2,x sta val2+1 dex lda col1,x sta $d021 sta $d020 lda col2,x sta $d022 inx dey bne br1 val1 lda #$00 ;badline code. Y=0 sta $d021 ;NTSC : change this to sta$d021,y sta $d020 ;NTSC : change this to sta$d020,y val2 lda #$00 sta $d022,y nop nop ldy #$07 inx cpx #$22 ;this value should be $x2 or $xA bne br2 jmp loop * = $1100 ;test colors - new page = to avoid +1 cycle col1 .byte $01,$00,$01,$00,$01,$00,$01,$00 .byte $01,$00,$01,$00,$01,$00,$01,$00 .byte $01,$00,$01,$00,$01,$00,$01,$00 .byte $01,$00,$01,$00,$01,$00,$01,$00 .byte $01,$00 col2 .byte $02,$00,$02,$00,$02,$00,$02,$00 .byte $02,$00,$02,$00,$02,$00,$02,$00 .byte $02,$00,$02,$00,$02,$00,$02,$00 .byte $02,$00,$02,$00,$02,$00,$02,$00 .byte $02,$00
base/rasterbars_4_source.txt · Last modified: 2022-03-16 09:27 by erhan