Nes/Famicom with separate CPU and APU

Discuss hardware-related topics, such as development cartridges, CopyNES, PowerPak, EPROMs, or whatever.

Moderator: Moderators

Post Reply
User avatar
Fodelao
Posts: 6
Joined: Thu May 05, 2022 11:07 pm

Nes/Famicom with separate CPU and APU

Post by Fodelao »

Guys one thing that has occurred to me lately is if it would be possible to reverse engineer the nes/famicom APU to make it work alongside the original MOS 6502 identically to the ricoh RP2A03 and get a nes/famicom console with separate CPU and APU.

Would it be possible to do this in order to keep legacy games compatible?

Because if it is and if the audio stayed true to the original, that would be a release from the dependence of the few RP2A03 that remain.

I worry about the shortage of nes/famicoms that will unfortunately be progressive and inevitable and, as I'm old school, I'm not an admirer of FPGA solutions.
User avatar
rainwarrior
Posts: 8734
Joined: Sun Jan 22, 2012 12:03 pm
Location: Canada
Contact:

Re: Nes/Famicom with separate CPU and APU

Post by rainwarrior »

Yes, you could* probably substitute a regular 6502 for the 2A03's CPU if all the other stuff was duplicated externally, but I don't think it would achieve your goal?

There is no equivalent IC for the non-6502 parts of the 2A03. If you don't want to use an FPGA to replace it, there's not really anything else that's practical?

If you did use an FPGA for it, it would probably be much easier to do the whole 2A03 in there rather than try to make something to complement an original 6502.

What are you looking to do?


* I think there are one or two known games that rely on the disabled decimal functionality of the 2A03, but these rare cases could possibly ignored or patched.
Post Reply