is there any way to put a nrom rom with chr ram (instead of normal chr rom) on a normal nrom board?
I'm interested in the rewire instructions as well because RHDE needs this configuration (27C256 + 6264 CHR RAM).
It should be possible the same way people do with FF3 repros or the various mmc5 repros that use ram instead of rom. If your rom is only 16K you might be able to cheat and use a UNROM board.
As long as the cartridge connector has the gold-plated finger for the CHR /WR signal, transplanting in an 6264 RAM is pretty easy.
But if it doesn't, you're probably better off getting an entirely new PCB made instead.
huh? i think i tried to drop a chr ram chip in with no rewiring and it didnt work
lidnariq wrote:
As long as the cartridge connector has the gold-plated finger for the CHR /WR signal, transplanting in an 6264 RAM is pretty easy.
But if it doesn't, you're probably better off getting an entirely new PCB made instead.
I didn't say "no rewiring", I said "pretty easy". The difference between a 28-pin 8KiB mask ROM, UVEPROM, EEPROM, and SRAM is ≈only the /WR strobe.
Looking at two boards (an NES-CNROM-256-05 and an NES-NROM-256-02) I have, PPU /WR has a gold plated contact, but no traces, so you'd need to remove the resist and solder a jumper of some sort in.
If it's like the MHROM boards I used when I made Garage Cart, you might have to cut a notch in the cart shell above the PPU /WR pin. Because the pin didn't fully extend to the inside part of the cart shell.