Mednafen PSX - wrong EU bios

Libretro Cores
#1

Hi,

I was wondering, why some of my psx games never worked and now I found the issue.

The Mednafen PSX cores are looking for the wrong EU bios file, as you can see in the mednafen_psx_(hw_)libretro.info file. There is the false md5 checksum for scph5502.bin.

scph5502.bin (md5): 32736f17079d0b2b7024407c39bd3050

The checksum is for the scph5552.bin bios file. For scph5502 it should be:

scph5502.bin (md5): e56ec1b027e2fe8a49217d9678f7f6bb

As a workaround I renamed a scph5552.bin to scph5502.bin and replaced the file in my bios directory. Now my games are booting correctly, but you should consider to adjust the issue in the mednafen psx cores.

Thanks :slight_smile:

#2

Made a pull request with the fix you proposed, hopefully it will get merged soon!

EDIT

Are you sure e56ec1b027e2fe8a49217d9678f7f6bb is correct?

Because I have information saying otherwise:

[quote]description SCPH-5502/SCPH-5552 (Version 3.0 01/06/97 E) name ps-30e.bin size 524288 crc d786f0b9 md5 32736f17079d0b2b7024407c39bd3050 sha1 f6bc2d1f5eb6593de7d089c425ac681d6fffd3f0[/quote]

And 32736f17079d0b2b7024407c39bd3050 matches the .info file

#3

bios for pal is actually a correct dump, this case must be related to some pal games having protection and what you have is actually a patched bios. i can only find one link, and that md5 states its a bad checksum.

#4

I reverted the pull request because the md5 in the current .info file is correct and matches mine too, they all match.

@steff You must have a incorrect dump.

EDIT

This should definitely clear things up:

8dd7d5296a650fac7319bce665a6a53c = match

490f666e1afb15b7362b406ed1cea246 = match

32736f17079d0b2b7024407c39bd3050 = match

#5

Sorry, my mistake :zipper_mouth_face:

My bios files were downloaded from the …paradise site. It was a pack with 15 different ps1 bios files.

I believed, different models also mean different md5 checksums. But I was not the only one, who used the wrong file :wink:

#6

As long as my reverted pull request wasn’t merged there is no harm done.

But I will certainly do a more thorough background check next time before I’m jumping in making pull requests.

Thank god for databases!

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