JMP problem

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JMP problem
by Zepper on 2008-02-26 (#31243)

- I tried out CMC'99 Stars Demo and my emulator traps a bad opcode (03h) at PC=8D8Bh. Well, I though it would be caused by a previous JMP (00E3), but previous JMPs were trapped and seemed to work just fine.

- Could someone help me?

by ccovell on 2008-02-26 (#31244)

Well, since I'm the one guilty for it, I'll guess that it's because the music (Journey to Silius rip) depends on all $800 bytes of RAM being set to 0, but I only cleared $700 bytes, if I remember correctly.

by Zepper on 2008-02-26 (#31245)

- True, the demo works with all RAM set to zero. Well, thanks for the reply.

EDIT: the same occurs with Sayoonara! demo. If the RAM isn't zero, there's no sound playing.

by dvdmth on 2008-02-27 (#31260)

Don't you just love these old hacks/demos that were never verified on real hardware and made bad assumptions about how things worked?

by Zepper on 2008-02-27 (#31279)

dvdmth wrote:
Don't you just love these old hacks/demos that were never verified on real hardware and made bad assumptions about how things worked?

It seems so... but they're very cool anyway.

by Dwedit on 2008-02-27 (#31286)

dvdmth wrote:
Don't you just love these old hacks/demos that were never verified on real hardware and made bad assumptions about how things worked?

Don't forget Translations! Final Fantasy 2 and 100 World Story fail on hardware.