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Project schedule poll
🕑 Added 2023-09-30 17:25:30 +0000 UTCIt's been a while since the last update !
Explaining this is a simple fact: although I've been hard at work on the Super A'Can sound chip, for now there hasn't been much exciting findings that I could share.
Tracing is now 90% done and the schematics currently consist of 42 pages (have a look on Github) but careful analysis to actually understand how things work has just begun.
Following part of the address decoding logic led to the DMA registers and counters, which addresses match MAME's source. Many undocumented control bits are used and need further research.
The mysterious register that Splash5 encountered when dumping the internal ROMs was found. It serves as a timer reset to disable the ROM after a precise period.
Part of the joypad related registers also make sense, with some undocumented bits that might have been used for peripherals that never saw the light.
I haven't started digging into how the actual sound generation logic works yet. All I know for now is that sound parameters are stored in giant shift registers, not unlike Yamaha did for their FM chips (but for different reasons).
Right. Now for the real talk.
The main reason I'm writing this post is because I'm currently faced with a dilemma:
Manuel Montoto "Debvgger" has sent me the elusive R800 and S1990 MSX Turbo R chips for reverse-engineering.
The R800 is a custom upgraded Z80 with a 16-bit ALU, faster memory access and memory mapping which was made by Yamaha.
The S1990 is a I/O / interface / glue logic chip made by NEC.
Both were decapped and imaged successfully but I haven't started any tracing work yet.
Here's the question: Should I pause the Super A'Can project to give priority to these two MSX chips, which might be interesting to a larger community ?
(*: Assuming there's any Super A'Can community...)
Comments
Roberto Lari
Please finish the Super A'Can console, I would like to try those few games available for this console.
Joseph Milazzo
Once you start the Furtek train don’t stop! It’s so hard to get back into things. But I can understand burnout? Question is are you burnt out on it and need a break?
