Naomi X76F100 repair attempt, help required.

[Ace`]

I've got a early Naomi motherboard that is working apart from error 03 caused by a bad X76F100, usually I'd take one from a scrap board but the only scrap boards I have use the newer 93C46 eeprom. I ordered some X76F100 chips from China thinking I could just program the data from mame on one and solder it in place and be done. Once they arrived I quickly noticed my expensive programmer (Elnec Beeprog 2) doesn't support them though, and neither do any of the other programmers I own.

Plan B was to use the 'dev' bios from mame, this bios looks like it was originally used to repair boards but as nothing is ever simple I am not sure how to use it properly, anyone tried this before? or got documentation for this bios?

Some emulated screen shots of the bios I am talking about.

 

[Ace`]

For anyone that stumbles across this post looking for the same fix, I wasn't able to program the blanks I bought unfortunately (for now at least) but I found an old post by MetalliC that suggested taking the chip from a donor cartridge. I had one in the junk pile and can confirm this does work, I thought the one on the cartridge would be different to the one on the motherboard but apparently not.

 

[youpla]

Hi @Ace,

I have an naomi board with Error 03 as you.
Unfortunatly I didnt' have junk noami cartridge and my junk noami boards didn't have this ic.
Did you manage to flash new X76F100 ?

If yes could you put bin file on this thread ?



Best regards, Nicolas

 

[Ace`]

I don't have a programmer that will read or burn X76F100 chips unfortunately but there is a dump in mame that *should* work. New X76F100 chips can be found on aliexpress but not much use unless you have a programmer that supports them or know someone that does.

 

[youpla]

Hi @mettaliC,

Thanks a lot for your reply and for attachment. My cheap tl866 programmer doesn't support x76f100.
As you, I will try to get this ic from a junk cartridge that I have to buy.
According to you, do you know if all games cartridges have this chip or only few of them?

Best regards, Nicolas

 

[Ace`]

I assume you mean me, you're better off finding someone with an eetools programmer that can program one as even if you do get a cartridge with the correct chip it's most likely dead and the reason the cartridge doesn't work.

That being said 171-7919A, 171-8132B and 841-0017C cartridges seem to have them. I took mine from a Mobile Suit Gundam capcom cart.