Posted By
Csabo
on 2024-07-23
19:01:35
|  Re: Cartridge ROM Hello World
This would work:
org $8000
jmp start ; cold start
jmp start ; warm start
db 1
db "CBM"
start lda #$55
sta $FF19
rts
ds $C000-*
The first instruction should be a jump to cold start, the second jump to warm start. The "CBM" bytes are the markers that the ROM checks to see if there's a cartridge there. This will just turn the border green and that's it (to avoid any more complexity, like paging). If you compile this, make sure there's no "program header" (normally the first two bytes in program files contain the loading address), then place it into ROM C1/C2/C3 Low in YAPE, it should work. |
