Posted By
Csabo
on 2007-11-30
21:29:28
|  Re: Chr$ reprogramming
To turn on user defined character sets, you would do this:
10 POKE DEC("FF12"), 0 : POKE DEC("FF13"), DEC("38") : REM $38 = address of character set
This will point the character generator to the $3800 - $4000 area (upper end of C16's memory, I think it's quite common). But by default, there's "garbage" there, so you will have to define the characters. From basic this would work:
20 READ C : FOR I = 0 TO 7 : READ B : POKE DEC("3800") + C * 8 + I, B : NEXT I
30 DATA 255, 1, 2, 4, 8, 16, 32, 64, 128
This would define character 255 as a slanted line. (Keep in mind that character 255 is not visible by default, it would be reverse of 127 - unless you turn on 256 chars by POKE DEC("FF07"), DEC("88") ).
Does it ring a bell? Hope it helps  Another good way of getting this info would be looking around in the game archive, and checking the screenshots for basic games with custom chars. Chances are, their basic listing would show something similar to this. |
