SPC700 Unusable Memory??

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SPC700 Unusable Memory??
by on (#115306)
I am using TASM to assemble my SPC700 binaries.

I dunno what the problem is, but $00-$04, whether zero-paged or absolute, will not work with my programming. I had some problems with several other absolute addresses. For some reason, the zero page addresses above $03 that I have tried (about 4) they are working for me.
Re: SPC700 Unusable Memory??
by on (#115307)
I am on Mac OSX, and I don't know of a good snes debugger (spc700 support) for this system.
Re: SPC700 Unusable Memory??
by on (#115309)
Does BSNES work on OSX? If so, that's what I'd use.

Echo processing can overwrite your code and data and cause all sorts of problems unless properly set up. Unless you're already doing so, I suggest that you start by writing 00h to S-DSP register 7Dh (EDL) and 20h to register 6Ch (FLG) to disable echo processing. Ideally you should wait 240 ms after doing this to ensure that the change has taken effect. After this you can upload your music code and data.

You should also use the CLRP instruction to make sure that the zeropage is located at 0000h..00FFh, unless you really want it at 0100h..01FFh.
Re: SPC700 Unusable Memory??
by on (#115310)
Yeah Mic_, I had a hunch it would be the Echo stuff, so I set the address somewhere far away and low and behold it works now :)

Also, I do clrp ;)
Re: SPC700 Unusable Memory??
by on (#115311)
thanks for the recommendation d5 on FLG register. trying that out now
Re: SPC700 Unusable Memory??
by on (#115312)
Yea that works a charm.