Any PGM Conversion info out there?

    • Apocalypse wrote:

      PascalP wrote:

      it’s more the removing parts of the original chips which gets tricky.
      Hot air is the key.It seems there are now Chinese SMD stations sold for ~$100 that can do a pretty good job.
      Or as a quick and dirty tactic I have seen a buddy use, heat gun, I am not kidding, but not for the faint of heart. That man has skills with a heat gun to quickly desolder components.
      Multis: CPS2│CPS3│ST-V│F3│GNET│TTX2│NAOMI
      Superguns: Jasen's MK30ADCAP│RGB's HASv3
      MB: NAOMI 1,2│MV-1FZ & MV-4│IGS PGM│SEGA ST-V│TAITO F3│TTX2,X3
      CAPCOM CPS*│RINGWIDE/RINGEDGE 1, 2│HYPER 64
      LINDBERGH Y/B|IREM M*|CAVE (ALL YOUR BASE)

      +++
    • lukemorse1 wrote:

      I bought the converted ones years ago and managed to finish off a full set.
      wish I knew about this earlier lol. As someone who owns all 3 of the conversions I can say that they play and sound great. Its nice to have 4 vertical shooters on the system instead of just Bee Storm :D
      is it really plays great same as original ?

      most of PGM games uses secured ARM coprocessor with game specific firmwares (later games fully run on ARM, "main" M68K is almost unused). Cave games is not exception and uses faster ARM for game logic calculations.

      how these conversions made then ? probably coprocessor routines was coded into M68K assembly and injected into games roms. as result of higher main CPU load more slowdowns is expected.
    • @MetalliC I checked the code in MAME and if I'm not wrong, the ARM is not even running. AFAIK the ARM will do a CRC check on the program ROM and if it doesn't match what it expects, it will just not decrypt anything. In that case useless encrypted code will reach the 68000 which will hang out inevitably. But if you are running decrypted code already, you are good.

      AFAIR in MAME there are some decryption routines for each program rom and that's it. Once you get the program rom decrypted, the game runs properly. Maybe there are some checks/answers that are emulated in MAME but if you run this code in a cart then those checks need to be bypassed, but as far as I could find out, the arm was not used. Can you please confirm?

      Thanks.
      * Arcade-projects, the site where you get the most of your arcade games.
      * If you want Drama go to Neo-Geo forum ---Darksoft
    • @Darksoft for quite big number of PGM games internal ARM firmwares still not dumped, you may see a lot of crappy HLE in src/mame/machine/ pgmprot_igs*****.cpp
      Cave games ARM HLE located at pgmprot_igs027a_type1.cpp
      void pgm_arm_type1_state::command_handler_ddp3(int pc)

      it seems I messed it with some other games, there is not really complex security math, so probably it was just hacked out at M68K code side.
    • Darksoft wrote:

      @MetalliC I checked the code in MAME and if I'm not wrong, the ARM is not even running. AFAIK the ARM will do a CRC check on the program ROM and if it doesn't match what it expects, it will just not decrypt anything. In that case useless encrypted code will reach the 68000 which will hang out inevitably. But if you are running decrypted code already, you are good.

      AFAIR in MAME there are some decryption routines for each program rom and that's it. Once you get the program rom decrypted, the game runs properly. Maybe there are some checks/answers that are emulated in MAME but if you run this code in a cart then those checks need to be bypassed, but as far as I could find out, the arm was not used. Can you please confirm?

      Thanks.
      So, it is possible to just burn a decrypted rom and replace the EPROM on a cart to change its language? that would be nice for me, since I'd like to have my korean Demon Front cart 100% in English. Is the decrypted ROM available somewhere? :D
    • aha2940 wrote:

      Darksoft wrote:

      @MetalliC I checked the code in MAME and if I'm not wrong, the ARM is not even running. AFAIK the ARM will do a CRC check on the program ROM and if it doesn't match what it expects, it will just not decrypt anything. In that case useless encrypted code will reach the 68000 which will hang out inevitably. But if you are running decrypted code already, you are good.

      AFAIR in MAME there are some decryption routines for each program rom and that's it. Once you get the program rom decrypted, the game runs properly. Maybe there are some checks/answers that are emulated in MAME but if you run this code in a cart then those checks need to be bypassed, but as far as I could find out, the arm was not used. Can you please confirm?

      Thanks.
      So, it is possible to just burn a decrypted rom and replace the EPROM on a cart to change its language? that would be nice for me, since I'd like to have my korean Demon Front cart 100% in English. Is the decrypted ROM available somewhere? :D
      We got one language-changed and hidden-characters-added rom already from the beautiful people on this board, I keep holding out for more because I too would love to make my games fully English.
    • New

      In Martial Masters the region is controlled by just one byte in the program rom. Could be the same for Demon Front?

      Can anyone here put up pictures of the compatible ROM boards for the Cave conversions? I have a regular Knights of Valour cart that looks like this:



      Would like to see how the compatible boards differ.

      On a side note, this cart can be upgraded to Knight of Valour Plus just by burning a new U1 rom.
    • New

      KalessinDB wrote:

      skate323k137 wrote:

      I Thought that may be the case after I upgraded puzzli2 yesterday. That one took a quick rom merge, but mame src and dumps made it easy. Maybe I'll upgrade my kov today too :)
      While you're looking, if you just HAPPEN to notice any more easy English conversions... ;)
      I'm just happy to finally see some more research and documentation for this system. It's really exciting.
    • New

      KalessinDB wrote:

      aha2940 wrote:

      Darksoft wrote:

      @MetalliC I checked the code in MAME and if I'm not wrong, the ARM is not even running. AFAIK the ARM will do a CRC check on the program ROM and if it doesn't match what it expects, it will just not decrypt anything. In that case useless encrypted code will reach the 68000 which will hang out inevitably. But if you are running decrypted code already, you are good.

      AFAIR in MAME there are some decryption routines for each program rom and that's it. Once you get the program rom decrypted, the game runs properly. Maybe there are some checks/answers that are emulated in MAME but if you run this code in a cart then those checks need to be bypassed, but as far as I could find out, the arm was not used. Can you please confirm?

      Thanks.
      So, it is possible to just burn a decrypted rom and replace the EPROM on a cart to change its language? that would be nice for me, since I'd like to have my korean Demon Front cart 100% in English. Is the decrypted ROM available somewhere? :D
      We got one language-changed and hidden-characters-added rom already from the beautiful people on this board, I keep holding out for more because I too would love to make my games fully English.
      Nice! Do you know where can I get this file? I've searched the board but it seems I cannot find it...