1x2 fade in/out

;```````````````````````````````````````
;1x2 show routine by erol/tempest
;jsr swset
;```````````````````````````````````````
show     inc $b3
         lda $b3
         cmp #$06
         beq sw1
         rts
sw1      ldx #$00
         stx $b3
sw2      lda sdata
         sta $d800,x
         sta $d828,x
sw4      lda $2698,x
         sta $0400,x
         clc
         adc #$40
         sta $0428,x
         inx
         cpx #$28
         bne sw2
         inc sw2+1
         bne sw7
         inc sw2+1
sw7      lda sw2+1
         cmp #<sdata+36
         beq sw3
         rts
sw3      lda #<sdata
         sta sw2+1
         lda sw4+1
         clc
         adc #$28
         sta sw4+1
         bcc sw5
         inc sw4+2
sw5      inc $b2
         lda $b2
         cmp #$09
         beq swset
         rts
swset    lda #$00
         sta $b2
         sta $b3
         lda #$00
         ldx #$10
         sta sw4+1
         stx sw4+2
         rts
;```````````````````````````````````````
sdata    .byte 0,0,11,12,15,7,1,7
         .byte 15,15,15,15,15,15,15,15
         .byte 15,15,15,15,15,15,15,15
         .byte 15,15,15,15,7,1,7,15
         .byte 12,11,0,0
;```````````````````````````````````````