OEM NESes and Famicoms are NMOS, and the 2A03 and 2C02 don't manage to drive anything above 4V. Only because of this do I say that it should be safe.bitcores wrote: ↑Sat Apr 22, 2023 4:10 pm Based on https://hackaday.com/2023/04/05/rp2040- ... -confirms/ looks like all but the ADC pins would be 5v capable for input, so if I were to do another one I'd to the address pins from GPIO 0-14, ROM CE 15 and then use level converters for the data pins from 16 onwards because at least one of the ADC pins needs to be used unless you stick with 16k ROM sizes.
But it's not truly 5v tolerant, so while it might work it may also reduce the life of the RP2040.
Note this is only true for:
PPU /RD, /WR
It is not true for:
/ROMSEL (from 74'139)
PPU /A13 (from 74'04 or 40'368 depending)
PPU A0-A7 (from 74'373)
CPU D0-D7 (SRAM is CMOS)
PPU D0-D7 (SRAM is CMOS)
Oh that's amazing. Makes me really unreasonably happy.Zoldark wrote: ↑Sat Apr 22, 2023 4:23 pm I don't know if this is relevant or not but I found a Japanese Site the other day that is selling a homebrew Mapper 218 PCB of some sort I think it may even be flash-able, you can order it through Buyee if you are willing to pay the additional International Shipping cost. They also have a Kazzo script for it..