I created few ROMs to use with VICE, sometimes were not working but few of them yes. Now I need to test ROM before I burn it and VICE 2.4 and nightly builds later works not with: Routine in 32K ROM copies data to RAM and have to execute them, but copying is done and no action. Look at this code:
.byte $ff // autostart has to be 1, but I changed it by examining Servant ROM and leave $FF
.byte $c3, $c2, $cd // CBM - characters with bit 7 on
start: ldx #00
copy: lda program,x
fncopy: lda fnkeys,x
jmp $1300 <======= this is not executed all above works, but this not
Can anybody help me where I do mistake and execution of copied routine at $1300 is never executed? Really are data copied, but execution is not performed...
Thank you for all.
Commodore 64 was great, Commodore 128 is bigger, better, faster and more powerful... Commodore 65 was almost here, now is back in Mega 65 and is more than ever was...
I download your "booterrom.bin" file and attach to VICE as Function ROM (I do not have EPROM burner to test real hardware).
I used VICE debugger... set break point to $800a and reset emulated machine. Here is what happens:
KERNAL starts code at $800a
Code is copied to $1300
Data is copied to $1000
CPU does JMP $1300
Data (code?) is copied to $1500
At $1313 attempt is made to JSR $F75C... but it crashes!
When the JSR at $1313 occurs, the MMU has value $16 for register $ff00... I don't know what BANK this corresponds with, but obviously the ROM you want is not available. I suggest you update your code to enable KERNAL (for example, LDA #0; STA $ff00). If you do that, JSR $F75C might work!