Glorious Irem M72 multi

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    • waiwainl wrote:

      PascalP wrote:

      Too bad I don’t own a M72 board... :(

      But if someone want to get rid of their original R-Type because of this multi, let me know :P
      Why, the multi does not work on R-Type.
      because R-Type is my ‘most wanted’ on that platform, wouldn’t mind getting an original one ;)
    • tom5151 wrote:

      Still looking for 1 board around 500$ (and not 500€), but I'm wondering if it's possible :)
      I wouldn't have bitten unless I had something coming from the seller already, so shipping was nothing on top, and I had some PayPal money floating around from eBay sales...

      There's also this stupid law in Australia that eBay and other vendors now charge 10% on top of every single sale made overseas for our "LOCAL" consumption tax. That's really a killer for a lot of avenues to get PCBs for us now too :/ -- I'm sure other Aussies on the board are equally pissed!

      Anyhows, re: a cheap M72... considering the dozens of people actively hunting now for the multi, I guess the only thing would be to look where others probably aren't or keep sniping for one at your price range. I can definitely say that there's not many boards around for sale super cheap -- in my search it's been a minimum $500 USD, but in pretty poor condition or with some issues.

      Speaking to people in Japan, it seems like the Japanese M72 version of Hammerin' Harry is quite hard to find and not common there by any means.

      I saw a reasonably priced Image Fight up on TOPS, but probably a little out of your price range, and (if it matters) the stickers on the ROMS weren't in-tact, but no badly priced considering their service.

      I'm sure something will show up sooner or later though, good luck in the hunt!

      Damn, sorry @PascalP -- sometimes insomnia has it's place in life (5am here...)
      Multis: CPS-2, CPS-3, F3, ST-V, MVS, M72, Naomi, G-Net
      PVMs: 2043MD, 20M2MDA, 20L2MD
      Devices: Sentinel Gold / Ultracade uVC / JAMMAizer! / XRGB-mini
      PCBs: VAPS Profile

      The post was edited 1 time, last by djsheep ().

    • PascalP wrote:

      because R-Type is my ‘most wanted’ on that platform, wouldn’t mind getting an original one
      It's everyone's most wanted, not just the best M72 game, but one of the best shooters ever made period. :thumbup:
      Darksoft: CPS3, CPS2, F3, MVS
      RGB: RECO v2, HAS v3
      invzim: Jammafier v1.6b
      XianXi: JNX Raiden, SC Taito Classic, SC Sega System 16/24
      Frank_fjs: JAMMA Extender (Special Edition)
    • jassin000 wrote:

      PascalP wrote:

      because R-Type is my ‘most wanted’ on that platform, wouldn’t mind getting an original one
      It's everyone's most wanted, not just the best M72 game, but one of the best shooters ever made period. :thumbup:
      exactly, so I’m just hoping some will hit the market as some people might get another board for the multi ;)
    • Apocalypse wrote:

      - Lighting Swords/Kengo: can also be supported on M72, in fact only main CPU code is encrypted and I have decrypted it. Now need to patch it for M72. Main CPU code is only 256kB so I have an extra 256kB to fit sound CPU code (which is only 64kB).
      - Major Title: can't be converted on any other Irem hardware because of double size VRAM2 and extra playfield
      - Pound for Pound: can be converted to M72 but then controls would have to be hacked cause game originally use trackballs. Not sure how good gameplay would be and if it is worth the effort (remember this is a top view boxing game with vertically oriented screen)

      I'm thinking of embedding all the ROMs that are unlikely to change (sprites, foreground, background, samples) for R-Type II and Lighting Swords/Kengo in the multi (there's enough free room for both of them) then if I ever complete the R-Type II conversion or do the Lighting Swords/Kengo one then it would only be a matter of updating a single ROM (containing main CPU code).
      You should feed Gadgetfreak the kengo decrypt, he will get it running on M82 in no time.
      This was the next 'lowest hanging fruit' for m82. Same deal as M92 decrypt but a lot bigger in size.
      If you want to test the decrypt on real kengo hardware i have the board here.

      Apocalypse wrote:

      Found the cause of the background tiles issue (which can also happen with foreground tiles BTW but affects very few tiles hence far less noticeable): flip bits are at different positions between M72 and M84.
      Also found an issue where when writing to video RAMs it sometimes overwrites sound CPU RAM, off course I've checked all my mapping mods and they are all correct. Also MAME doesn't seem to be able to catch what instruction is overwritting the sound RAM.
      This was where i got stuck on the dragon breed to m82 conversion. Video ram shit.

      All the m82 + 84 games throw 'crap' down the BOFFE line = the sound / MCU ram for the m72.
      The writes to B0FFE on the newer titles can be nopped and the game will function as normal.
    • twistedsymphony wrote:

      Have you looked at the M90 stuff? Bomberman would be an awesome addition if possible.
      Yes I did, main CPU and sound CPU are compatible but it's a completely different driver in MAME so I expect a lot of differences in video hardware.

      Hammy wrote:

      You should feed Gadgetfreak the kengo decrypt, he will get it running on M82 in no time.This was the next 'lowest hanging fruit' for m82. Same deal as M92 decrypt but a lot bigger in size.
      If you want to test the decrypt on real kengo hardware i have the board here.
      That or I release the M82 conversion in the meantime. I'm surprised how easy conversions between M72/M81/M82/M84/M85 are and that it wasn't widespread for some reason.
      You don't need specifically a Kengo board to test the decryption, any M84 board is fine.

      Hammy wrote:

      This was where i got stuck on the dragon breed to m82 conversion. Video ram shit.
      All the m82 + 84 games throw 'crap' down the BOFFE line = the sound / MCU ram for the m72.
      The writes to B0FFE on the newer titles can be nopped and the game will function as normal.
      I know that and this isn't the source of my issue, I've soon noped those writes (so as 0xB4000) but it made no difference.
      Looking for:
      - OutRun boardset even untested or not working
      - Sega Super Scaler hardware (Out Run, Model X, Model Y), even with faulty PCM chip



      01010011 01000101 01000011 01010010 01000101 01010100 00100000 01001101 01000101 01001110 01010101 00100000 01000111 01010101 01011001
    • Apocalypse wrote:

      That or I release the M82 conversion in the meantime. I'm surprised how easy conversions between M72/M81/M82/M84/M85 are and that it wasn't widespread for some reason.You don't need specifically a Kengo board to test the decryption, any M84 board is fine.


      I know that and this isn't the source of my issue, I've soon noped those writes (so as 0xB4000) but it made no difference.
      Please do if you can, the log files on this one are killer :)

      For the M84 yes, but the main cpu code needs adjusting further to get it working on older hardware - the new cpu can read longer opcodes than the old cpu and more.
      I bet kengo hardware can run unencrypted games as standard with some minor tweaks,will give it a go sometime.

      B4000 is something, I never worked out what it did. Gadget will know.
      It's only easy now with the new tools and knowledge that has been worked out over the years.
    • Hammy wrote:

      Please do if you can, the log files on this one are killer :)
      For the M84 yes, but the main cpu code needs adjusting further to get it working on older hardware - the new cpu can read longer opcodes than the old cpu and more.
      Not sure what you mean by the log file?

      And there's nothing to adjust for older hardware, Kengo uses a V35 which is the micro-controller version of the V30. Irem had no other choice if they wanted to have the keys hidden.
      Looking for:
      - OutRun boardset even untested or not working
      - Sega Super Scaler hardware (Out Run, Model X, Model Y), even with faulty PCM chip



      01010011 01000101 01000011 01010010 01000101 01010100 00100000 01001101 01000101 01001110 01010101 00100000 01000111 01010101 01011001
    • R-Type II now has sound, it was just me being stupid and missing an output to a port.
      Weird enough this port then makes some registers to be wrong and gets the program to overwrites itself.

      Last obstacle: samples.
      Looking for:
      - OutRun boardset even untested or not working
      - Sega Super Scaler hardware (Out Run, Model X, Model Y), even with faulty PCM chip



      01010011 01000101 01000011 01010010 01000101 01010100 00100000 01001101 01000101 01001110 01010101 00100000 01000111 01010101 01011001

      The post was edited 1 time, last by Apocalypse ().

    • acblunden2 wrote:

      I see some sprinkling into this discussion of other Irem board models. Does this mean this multi can potentially support more than just the M72?

      If that is the case, my M84 Hammerin' Harry won't be stuck out in the cold.
      From a software point of view the M72 multi can also support converted games from M81/M84/M85.
      But from a hardware point of view it only fits on a M72 boardset (again except R-Type due the simpler romboard it uses).

      A multi for M84 is possible but:
      - the romboard is too close to the motherboard board for a multi with EPROMs on sockets to fit. A riser board would have to be designed, not really a problem but the look isn't going to be great.
      - there are 2 different romboards on M84. Again not a problem if the designed board from the kit accepts 2 different socket layouts.
      - there are also 2 different motherboards. Probably not a problem regarding layout, might be regarding CPU used.
      Looking for:
      - OutRun boardset even untested or not working
      - Sega Super Scaler hardware (Out Run, Model X, Model Y), even with faulty PCM chip



      01010011 01000101 01000011 01010010 01000101 01010100 00100000 01001101 01000101 01001110 01010101 00100000 01000111 01010101 01011001