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KoshiroKazuma

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I am converting CPS1 games recently and trying to make a 2 in 1 multi B-Board. I own several 91634B-2 and 91635B-2 boards.
From the silkscreen,it seems that:
The 91634B-2 accepts JEDEC EPROM for both GFX and PRG. But I cannot find any 8Mb(512K X16) JEDEC EPROM for it. Because I merged 2 game roms together...
The 91635B-2 Mask ROM type B-board can accept NON-JEDEC EPROM for GFX. I can use M27C800. But the PRG part only accepts JEDEC ones. So, as above, the same question...

From this article :https://wiki.arcadeotaku.com/w/CPS1_Repair_Logs
It seems that the jumpers can control EPROM types (JEDEC or Non-JEDEC) But it's all about 89624B board. No more infomation about later board versions.
Do you guys have any info about the jumpers?
 
I don't think you can easily get away with a simple jumper change for that because the 27C4096 and 27C4100 (or 27C400) have completely different pinouts. More than just the location of a output enable (OE) pin...

BUT

The PJ01 jumper might be controlling the lower portion of the program ROM sockets (i.e. 24-31) and you "may" use 27C20's in place of 27C010's to host multiple program images.

Just a thought... Never tried it and the purpose of PJ01 may not be what I say. You have to check it by yourself with a multimeter or someone more into CPS1 hardware may step in here...

And of course, you also have to re-arrange your bigger program ROM images (split) for 27C010's...
 
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OR, you may want to use flash ICs with DIP adapters instead of using classic windowed EPROMS. I've seen many bootlegged/converted CPS1 games populated with flash ICs on DIP converter PCBs.
 
I don't think you can easily get away with a simple jumper change for that because the 27C4096 and 27C4100 (or 27C400) have completely different pinouts. More than just the location of a output enable (OE) pin...

BUT

The PJ01 jumper might be controlling the lower portion of the program ROM sockets (i.e. 24-31) and you "may" use 27C20's in place of 27C010's to host multiple program images.

Just a thought... Never tried it and the purpose of PJ01 may not be what I say. You have to check it by yourself with a multimeter or someone more into CPS1 hardware may step in here...

And of course, you also have to re-arrange your bigger program ROM images (split) for 27C010's...
Thanks for your info.
Actually someone in China can do such kind of 2-in-1 on one B-Board. For example, wof and dino. The guy uses socket 1-17 for GFX of the 2 roms and socket 20-28 for the PRG of the 2 roms.
He didn't use any flash chip, just the windowed EPROM. There is a DIP switch on the position of jumper SPJ1 and VJ01 to change the game.
I have asked the guy how to split or rearrange the PRG part, but he didn't want to tell me ... :( :(
 
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