Midway Wolf conversions

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    • i was wondering on the tests where people have added the 32.768KHz crystal and the MK41T56N, have they replaced the u57 gal chip to match the game. given the proximity of the u57 to the MK41T56N. the u57 gal may be the logic to make use of the MK41T56N and the crystal when switching from games like mk3 to nba hangtime. also it appears the u57 gal is game specific. so it may matter that the gal match the game exactly to prevent errors (specifically the cmos errors seen in one of the earlier posts). I am just guessing and havent tested but was looking at my wolf board
    • I haven't replaced the GAL chip during my hangtime conversion. I guess U57 is sound section related because I once replaced it during a repair that the sound section was not working.

      Regarding UMK3 to XXX conversion, only the UMK3=>MK3 conversion worked for me. UMK3=> Hangtime, I suffered CMOs erros and periodic game hangs/resets. So I converted it back to UMK3 and sold the PCB as it is :)
    • ok wanted to include the correct GAL chips here:

      open ice u57 A-20255 (no MK41T56N)


      mk3/mk3u u57 A-20093 (no MK41T56N)


      Rampage u57 A-20255 (no MK41T56N)



      does anyone know the GAL chips for the other games?


      as for which games use which EPROMS and the GAL:

      4-rows (16x 8Mb graphics roms):

      2on2 open Ice Challenge: u118-u133 u57 A-20255 (no MK41T56N)
      Rampage World Tour: u118-u133 u57 A-20255 (no MK41T56N)
      WWF Wrestlemania: u118-u133 ?

      5-rows (16x 8Mb graphics roms + 4x 4Mb or 8Mb graphics roms):

      Mortal Kombat 3: u114-u117 (4Mb), u118-u133 (8Mb) u57 A-20093 (no MK41T56N)
      NBA Hangtime: u110-u113 (8Mb), u118-u133 (8Mb) ?
      NBA Maximum Hangtime: u110-u113 (8Mb), u118-u133 (8Mb) ?
      Ultimate Mortal Kombat 3: u110-u113 (8Mb), u118-u133 (8Mb) u57 A-20093 (no MK41T56N)

      The post was edited 4 times, last by rocket ().

    • I solved the mystery of the 'CMOS CHIP U49 BAD' error encountered with conversions to NBA Hangtime and Open Ice...

      Firstly, U49 is NOT the CMOS RAM - it's the work RAM (a 4Mb DRAM). The CMOS RAM is actually the 28 pin SOIC at U62. My UMK3s have an LH5268AN-10LL fitted, which is an 8Kx8 SRAM. Open Ice and NBA Hangtime have an LH52B256N-10LL, which is 32Kx8. See the problem? ;)

      In order to get my UMK3 to Open Ice conversion working, I had to do the following:

      1. Remove U62 and install an LH52B256N-10LL.
      2. Remove the 4.7K resistor at R138.
      3. Add a zero ohm link at R644.

      Now it works great, with no CMOS errors! (Hopefully)
      Images
      • CMOS.JPG

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