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Is the SGROM wiring the same as SNROM as far as making a cart from a chip?

I think it should be, as the only difference in the board specs is one has WRAM and the other does not. It shouldn't change what you need to rewire.

Yes of course there is absolutely no difference. In fact most Nintendo made roms of the same size have the same pinout, so all conversions applies to all of them. There is weird exeptions, like boards with numbers in them (SL1ROM, etc....).

Bregalad wrote:Yes of course there is absolutely no difference. In fact most Nintendo made roms of the same size have the same pinout, so all conversions applies to all of them. There is weird exeptions, like boards with numbers in them (SL1ROM, etc....).

I tried several SGROM boards wired the same way as SNROM, but cant get her going, any clues? Thanks!

Bumping this as I just had the same problem. My wiring is totally fine. FWIW im using Tecmo Baseball as a donor for the translated Bionic Commando rom. There might be a difference because of the CHRAM but I dunno.

Just in case someone comes looking at this, SGROM boards do not use WRAM whereas SNROM does. SGROM boards cannot be used for SNROM games. You might want to have a look at INL's flash carts and programmer here: http://www.infiniteneslives.com/products.php.

Oh I didn't know that existed. Thats awesome! But my problem is im using an SGROM game to make anothe SGROM game. Altho one is SGROM-02 and the other is SGROM-03. And the wiring I used was the SNROM wiring (Pin 1, 2, 24, 30, 31, 2-24H, 30-1H, 16-24)

Using SGROM to make an SGROM game should be fine, so long as you get the rewiring from mask ROM to UV EPROM or flash correct.

My wiring is clean enough. Nothing jumping. Also the EPROM was verified. Cant get my head around this. Ive also read people with similar problems with no solution. Did I just not rewire correctly?

Ill specify a little more and chalk it up to a learning experience. Im using the famicom rom of Bionic Commando thats translated, 256k PRG. Altho Tecmo Baseball is SGROM-02 and its PRG is 128k if that does anything.

What kind of eprom chip are you using? If its a flash rom then you need to tie the /WE pin (pin31) to GND or VCC. Not doing so will cause the game not to load IIRC...

Ah, I think that might be the problem. Its an AM27C020.

I have pin 24 grounded to pin 16, hole 1 to pin 30 and hole 24 to pin 2.

I also wanted ask for my own edification, what are the circumstances where an eeprom is necessary?

There should be no circumstance under which you could only get an otherwise equivalent UVEPROM or EEPROM but not both working.

They often have different wiring, of course.

For games originally designed for a mask ROM, such as virtually all NES games, either will work. But if a game is designed to have EEPROM save, you need EEPROM. For example, there's been occasional talk over the past few years of leaving the battery out of new designs in favor of copying the persistent parts of PRG RAM to a block of the game's flash memory.

Thanks for the help guys. I still can't quite figure out why this isn't working. Is there any more info I could give you guys that'll shed more light on this? OR is it i'm just not understanding something that's pretty simple?

I used my Bionic Commando rom and patched it with this ips http://www.romhacking.net/hacks/82/.

Patch worked, opened it up, worked. Used the NES mapper, says its SxROM, 256 PRG, no VRAM.