Irem M-92 Major Title 2 Conversion to R-Type Leo

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    • Irem M-92 Major Title 2 Conversion to R-Type Leo

      I have an Irem M-92 Major Title 2 board in the mail purchased specifically with the intention of converting it over to R-Type Leo. The two boards are similar, but the sound code is encrypted on both. Two years ago, a guy going by VxC worked out a way to decrypt the R-Type Leo sound code and re-encrypt it to match up to Major Title 2, as documented here:

      jammaplus.co.uk/forum/forum_po…2-to-rtype-leo-conversion

      The problem now is that VxC's site with the sound ROMs is down, and Google hasn't helped me in finding it. Does someone here have the same conversion, and if so, would you be willing to dump the sound ROMs for me? Golf is cool and all, but I really prefer shooting aliens...

      Another note: I read that Darksoft once considered taking on an Irem M92 conversion aid tool. It's a pity that it never happened - the M92 doesn't have a lot of games, but the games it does have are very high-quality. Another guy in the thread I linked above was able to get conversions for Undercover Cops and In The Hunt mostly functional, but he pulled the links. I may tackle it myself at some point - I'm a coder by trade, but I haven't tackled encryption or MAME debugging before, so there'd definitely be a learning curve.
    • My friend has the conversion ROMs, I'll bug him about getting them up/hosted again.
      I don't have the tools to dump my board (which is a conversion).

      Also I'm told the conversion set for Undercover Cops Alpha never worked correctly.
      I'm not sure about In the Hunt (my board for that game is original/real).



      Darksoft/Apocalypse: CPS2, CPS3, F3, MVS, S16
      RGB: RECO v2
      invzim: Jammafier v1.6b
      XianXi: JNX Raiden, SC Taito Classic, SC Sega System 16/24, Namco System 11/12 KHA
      Frank_fjs: JAMMA Extender (Special HAS Edition)
    • jassin000 wrote:

      My friend has the conversion ROMs, I'll bug him about getting them up/hosted again.
      I don't have the tools to dump my board (which is a conversion).

      Also I'm told the conversion set for Undercover Cops Alpha never worked correctly.
      I'm not sure about In the Hunt (my board for that game is original/real).

      That would be wonderful if your friend could provide or host the ROMs.

      I've been reading up on the process another guy named Apocalypse did to recreate the conversion process here:
      translate.google.com/translate…viewtopic.php%3Ft%3D56664

      His approach looks straightforward to reproduce, so I might take a stab at it myself in the next few weeks. The hard work of determining the decryption tables for the different Irem M92 boards has already been done by the MAME Team. A conversion tool would just need to know what M92 ROMs you're providing it with for conversion and what your target donor board is. The tool would then run the sound code through the appropriate decryption and re-encryption tables appropriate to the game and the target board.

      That said - I'd still like a copy of the converted ROMs anyway - partly so I can verify that my own code produces the correct output, and partly because I'd like to start blasting aliens ASAP!
    • I've been deep-digging the 'Net everywhere for those conversion patches and have yet to turn them up. As I understand it, the original patch creator pulled it down because he was unhappy with all the board conversions selling for big $$$ on EBay. I'm crossing my fingers that Jassin's buddy will save the day for us.
    • I would love to do and play some conversions. I for one would like to learn more on this topic. But, I also ask that any conversion roms have some kind of identifying marker, lets say at bootup, to say its a conversion. Way too many people trying to pass off bootlegs as originals.


      Wanted: Batsugun, Battle Garegga, Battle Bakraid, Deathsmiles, War of Aero
      13/14" TriSync Tube/Chassis, Vewlix Shipping Brackets
      If you have any of these for sale/trade let me know please and lets make a deal :thumbup:
    • Just saying in case this thread steers into other conversions, M92 boards are difficult enough to get. I think Darksoft creating an m92 multi would be the best solution :D


      Wanted: Batsugun, Battle Garegga, Battle Bakraid, Deathsmiles, War of Aero
      13/14" TriSync Tube/Chassis, Vewlix Shipping Brackets
      If you have any of these for sale/trade let me know please and lets make a deal :thumbup:
    • Nice! I'll put these in my Dropbox as well for future potential need.

      I understand the original creator getting annoyed with people selling conversions for big $$ off his work. But no matter what there will always be people who will profit off bootlegging and stealing other people's work, especially in this hobby due to the huge prices things can sell for :(
    • OMG - jepjepjep you are a saint! I am beyond thrilled right now - seriously. If you're ever in my neighborhood, let me know and I'll buy you dinner.

      My Major Title 2 board arrived in the mail today - now I just have to wait for the right EEPROMs to arrive. The original conversion instructions say to repurpose the chips already on the board, but I want to preserve them in case I ever want to switch the board back to being authentic. I'll definitely update this thread after the conversion is done.

      I still plan on proceeding with developing and eventually releasing my own tool for decrypting and reencrypting the sound code for these boards - hopefully it'll enable other M92 conversions as well. Having these files in hand will allow me to validate that my tool works correctly. Thank you, thank you, thank you!
    • ShootTheCore wrote:

      OMG - jepjepjep you are a saint! I am beyond thrilled right now - seriously. If you're ever in my neighborhood, let me know and I'll buy you dinner.

      My Major Title 2 board arrived in the mail today - now I just have to wait for the right EEPROMs to arrive. The original conversion instructions say to repurpose the chips already on the board, but I want to preserve them in case I ever want to switch the board back to being authentic. I'll definitely update this thread after the conversion is done.

      I still plan on proceeding with developing and eventually releasing my own tool for decrypting and reencrypting the sound code for these boards - hopefully it'll enable other M92 conversions as well. Having these files in hand will allow me to validate that my tool works correctly. Thank you, thank you, thank you!
      It would be awesome to meet up someday. Either in Utah or if you come down to southern CA. I'm glad to be able to help. Best of luck on your tool development, that would be incredible!
    • jepjepjep wrote:

      Best of luck on your tool development, that would be incredible!
      Yea we need a proper conversion set for Undercover Cops Alpha!
      Darksoft/Apocalypse: CPS2, CPS3, F3, MVS, S16
      RGB: RECO v2
      invzim: Jammafier v1.6b
      XianXi: JNX Raiden, SC Taito Classic, SC Sega System 16/24, Namco System 11/12 KHA
      Frank_fjs: JAMMA Extender (Special HAS Edition)
    • jassin000 wrote:

      jepjepjep wrote:

      Best of luck on your tool development, that would be incredible!
      Yea we need a proper conversion set for Undercover Cops Alpha!
      Yes we do :D


      Wanted: Batsugun, Battle Garegga, Battle Bakraid, Deathsmiles, War of Aero
      13/14" TriSync Tube/Chassis, Vewlix Shipping Brackets
      If you have any of these for sale/trade let me know please and lets make a deal :thumbup: