borcol.md

Border Colour

Checks the raster position to flash the border with a solid colour.

Start with SYS 49152 and stop by pressing any key.

Code

10 borcol=$d020
20 raster=$d012
30 getin=$ffe4
99 !
100 *=$c000
110 loop lda raster
120 bne loop
130 lda raster-1
140 and #%10000000
150 bne loop
160 inc borcol
170 jsr getin
180 beq loop
190 rts