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kalymos / PsNee

PsNee, an open source stealth modchip for the Sony Playstation 1
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PM-41 NTSC J #43

Open some-git-user opened 11 months ago

some-git-user commented 11 months ago

ATtiny85 does not load originals/backups from PAL region, but japanese originals/backups running fine. I can repeatedly hear the disc spinning up/slowing down until I land in the memorycard/cd player menu. While in the menu, the disc is still spinning up/slowing down (I don't see the "insert PS disc" screen).

wyatt8740 commented 11 months ago

Mid/Late model Japanese systems have to have the discs patched to claim to be NTSC-J or have their entire BIOS chips replaced, because there's a secondary check in the BIOS code that the modchip (which manipulates the mechacon) cannot bypass (yet, at least). The only PAL PSX that does this is the PM-41(2), and no north american units do the check.

So it's easiest to patch your game discs so that the BIOS thinks they're NTSC-J region. But it's not really something within the scope of this modchip to be able to fix (unless someone makes a hack like the one for the PAL PM-41(2) - which the ATTiny85 might not have enough pins to do anyway).

some-git-user commented 11 months ago

Thanks for the explanation. I think this is very important information and should be written down in the Readme. Up until now I thought only PAL PM-41 boards needed a BIOS patch to run region free.