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  1. ic3b4ll

    PacMania - music, but no sounds

    Run of the mill TTL logic. It's still being made!
  2. ic3b4ll

    PacMania - music, but no sounds

    Did you replace the 74LS04 at P4? The one connected to SNA14?
  3. ic3b4ll

    Location of Backup Rams on Slot MVH-1 change by Fram

    The datasheet states that address latching is done when CE goes low and there's a specific order for when to do it when writing. I think this is what may cause the incompatibility issues @stj has found. It wouldn't surprise me some implementations simply assume that a new address is latched...
  4. ic3b4ll

    Location of Backup Rams on Slot MVH-1 change by Fram

    @Apocalypse this was just @stj tricking me into reading the FM1808's datasheet. Well played...
  5. ic3b4ll

    PacMania - music, but no sounds

    @mathewbeall if you can, try to probe the RAM now and after you remove the YM2151... I think you may find something interesting. Also, at this point does the RAM error clear? What about after you remove the YM2151?
  6. ic3b4ll

    The Batman Forever Sound Project - Add Your Batman Bounty Cash!!!

    @Hammy I skimmed the DSP datasheet and I believe the CPLD is just there for bus access. The data and address buses are shared on the DSP IIRC. The memory map is known so it can *theoretically* be reverse engineered and reimplemented.
  7. ic3b4ll

    The Batman Forever Sound Project - Add Your Batman Bounty Cash!!!

    On standby until I find some time. The board is also used for NBA Jam Extreme so I talked a bit with @Hammy about it. I'm trying to get a proper workshop for my arcade related projects and hopefully when I do I will be able to put some speed on everything I have on the back burner.
  8. ic3b4ll

    PacMania - music, but no sounds

    Ok, the fact that it's the music that is missing is a major clue that the issue is on the YM2151 side of the sound generation circuit. If you look at the schematics you can see that the CUS121 is connected to the U2 RAM and the YM2151. Both of these are isolated from the sound CPU and can only...
  9. ic3b4ll

    PacMania - music, but no sounds

    Edit: removed incorrect explanation for why replacing the RAM at U2 could work. @mathewbeall I'm sorry, I forgot you had already replaced one of the RAMs. Yes, I mean the one at U2. I happen to be in the middle of organising my PCBs and have Pacmania at hand. I'll take a look at it and see if...
  10. ic3b4ll

    PacMania - music, but no sounds

    Since continuity is OK I would try and replace the RAM (HM6264). RAM is usually a weak spot on many boards, i.e. prone to failure. I think it's socketed so you can just use one from your good board if that's the case.
  11. ic3b4ll

    V61C16S35L SRAM replacement

    Yes. I looked at the datasheet just in case and it's fine.
  12. ic3b4ll

    Rockman 2 The Power Fighters

    It's common knowledge, I'm sure many people here can help. I'm in Europe, so it's not really feasible for me to do it for you. Maybe @ReplicaX can chime in?
  13. ic3b4ll

    Hello everyone, Looking to find a better home for my arcades!

    Welcome back to the stage of History!
  14. ic3b4ll

    Rockman 2 The Power Fighters

    Go here instead: http://arcadehacker.blogspot.com/2016/09/capcom-cps2-security-programming-guide.html
  15. ic3b4ll

    Rockman 2 The Power Fighters

    Too keep it as close to factory, you replace the battery and perform Arcade Hacker's desuicide process (https://github.com/ArcadeHacker). He was the one who researched it and managed to figure out how to restore the encryption/protection key back into the CPS2 games. Alternatively, just use an...
  16. ic3b4ll

    PacMania - music, but no sounds

    @mathewbeall always glad to help someone who is willing to work for their boards. Good luck! P.S.: don't forget the Fujitsu 245! Fujitsu TTL chips are... crap. Yes, that's the technical term.
  17. ic3b4ll

    PacMania - music, but no sounds

    Check the data and address buses too. You may have a stuck pin that is causing the processor to crash and it's more likely that is the issue since reset, halt and clock signals are okay(ish). You should have activity on all data pins and some or all address pins in a working CPU. In this case I...
  18. ic3b4ll

    How to simulate a button press using a microcontroller?

    I think this is what you need: SN74LVCC4245A
  19. ic3b4ll

    Testing BNC and VGA cable voltage and resistance

    @Joe if you're really in Tokyo then a CRT TV should be relatively straightforward to use. You can use the JP21 connector for true RGB. My experience using SCART is that CRT TVs accept pretty much everything you throw at them IF you use RGB.
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