Raiden checkpoint rom swap

[turntablism]

I read that the Japanese. raiden pcb have checkpoints and the us board not. Is that correct ?
So i have a japanese one and i want to burn a separate us rom set, that i have no checkpoints anymore.
Did somebody do that before and could tell me which rom i have to change ?

[nem]

I think it's just the JP version that has them.

Looking into the Raiden driver in Mame there's this bit on region swapping:

The country byte is stored at 0xffffd in the main cpu region,
(that's 0x1fffe in program rom 4).
0x80 = World/Japan version? (Seibu Kaihatsu) (distributed by Tecmo?)
0x81 = USA version (Fabtek license)
0x82 = Taiwan version (Liang HWA Electronics license)
0x83 = Hong Kong version (Wah Yan Electronics license)
0x84 = Korean version (IBL Corporation license)

Just tried it in Mame and if put 80 or 81 in 0xffffd you will have instant respawn. What kind of eprom do you have as the 4th program rom?

[turntablism]

Thanks, so i try to rewrite the eprom to 81. I have not removed the eprom yet. I don't know what kind it is.

[nem]

I would just get a replacement eprom for it. If you have the tools, you could dump your own rom (and make sure it's already in Mame), edit the rom data and program it to another chip. Easy enough to return back if you ever wanted.

[turntablism]

Yes, this is what i want to do but i dont know what kind of 32pin eprom i need.

20180909_171055-1161x1471.jpg

Tomorrow i get my burner and try it.

[nem]

Probably either a 27C1000 or a 27C1001. You'll know when you get your programmer.