Search results for query: *

  1. R

    Audio problem with MVS MV1F

    Coin sound and cursor move are SSG sounds generated directly by YM2610, pin 27, check everything on that line. other sounds are sent on 4 data lines, that mostly run along with the analog SSG out trace, to the YM3016. Check for bad things on these lines, pins 29, 30, 31, 64. your YM3016 or some...
  2. R

    AES stuck in watchdog (fast click of death), garbage screen

    C1 pin7 does only go to RAM. the other command signals also ony go to Work RAM WWU/L WRU/L are [W]ork RAM [W]rite enable [ U] pper / [L]ower and [W]ork RAM [R]ead (aka OE [O]utput [E]nable) enable [ U]pper / [L]ower So they command RAM on when data is written and read IMO it's never a good idea...
  3. R

    Interest Check - NEW MVS MULTI BATCH!!

    Ordered from SYG, thank you for making a new batch
  4. R

    Interest Check - NEW MVS MULTI BATCH!!

    count me on the train
  5. R

    1 slot graphics issue

    I am thinking L0 rom, or NEO-ZMC2. L0 handles vertical stretching, but the fact that you get alternating vertical lines on the solid blocks makes me think it's more likely the ZMC2 L0 is an SMD rom on MV1A, so you need a donor or bodge a DIP EPROM, even for just testing, and of course ZMC2 is...
  6. R

    Shock Troopers black screen / self rebooting

    There are some ceramics but it's very unlikely they are bad Since it does some kind of boot, P1 might be fine. P2 is a Toshiba and these have decently high failure rate in either carts or boards (bios) Unibios CRC check is a good start. And if a P rom is bad the good thing is they are...
  7. R

    AES failing VRAM DATA test on Neo Diagnostic BIOS

    It's a data error. The quote you posted is for address error. Bad ram chip is very likely in your case Also it's at 008000 which is the start of 4k / Fast vram, which are usually in DIP form (the CXK5814 in your case as with most AES I believe)
  8. R

    AES black screen sync issues (click of death?)

    https://wiki.neogeodev.org/index.php?title=NEO-D0 check all the purple pins, Xin / out is the master crystal, all the others are outgoing clocks. If all are pulsing check if each clock actually go to each chip needing it. check 68k address / data lines activity, each (I think) should be pulsing.
  9. R

    AES black screen sync issues (click of death?)

    That fast click means something early is bad. Do you have something to check activity, at least a logic probe, or an oscilloscope. Main crystal (if faulty usually results in literally nothing, not even click of death) goes into D0 that divides for almost all clocks. Some ICs might stick an...
  10. R

    AES black screen sync issues (click of death?)

    Does game actually launch ? Do you have sound, through either AV Out or headphones jack ? Did you try on composite cable, on a crt ? I have found that some MVS and pretty much all AES I've tested tend to have sync signals that throw off modern hardware, displays, scalers, etc.
  11. R

    Reverse engineering 161 in 1 cartridge to change Rom games

    Bro that's wild. Congrats for getting it done and fully documenting it
  12. R

    MV1B UniBIOS unable to set calendar?

    Check activity on test point TP1 (scope or logic probe), it goes high / low every second. If it doesn't, well there are several points to check : RTC power line 32.768 khz crystal, should be pulsating on at least on one leg crystal capacitors C2 C3 RTC itself, NEC µPD4990
  13. R

    MVS 6-SLOT - How bad does this board look?

    I'll go on a limb and say this doesn't look too terrible. As you say you can retin exposed traces, and maybe bodge wire if some lines are cut. The real work is figuring out if a chip is dead on the top board. You can do tests with the bottom board only with diag bios.
  14. R

    Pre PCM chip game conversion Magician Lord and Cyberlip

    I already tried a Magician Lord convert on modern boards and doesn't work, maybe with extensive rom data manipulation it coukd be done, as earlier games had ADPCM A / B stored separately. C data also needs some work as there are some glitches. Ultimately I used a puzzled donor. Repro PROG-EP and...
  15. R

    MV1AX MVS motherboard with watchdog click of death

    Capacitors labelled PC are Power Capacitors, 100nF ceramic. They are typically used near every IC to filter their switching noise. However they are not critical. Watchdog loop is CPU not getting program to execute right in one way or another basically (please all experts here correct me if I'm...
  16. R

    MV1B1 Stuck in service mode

    CRE401 can fail internally, on each line there's a pull up resistor, an inline resistor and a capacitor to ground. Cap failing short makes input always on. https://wiki.neogeodev.org/index.php?title=CRE401
  17. R

    MV1B1 Stuck in service mode

    MV1B has no F0 However, looking at pics, it looks like dips are connected to a NEO-BUF, which are notorious for failing.
  18. R

    29F032 protection permanent ?

    TOP3000 has an unlock command that does nothing in this case. GQ-4X4 has a Temp unlock checkmark that is grayed out, and I did not find anything to activate it, and there's no unlock command in menus.
  19. R

    29F032 protection permanent ?

    So it was sketchy as, but it actually worked in the end. Had to lift leg as the trace went under the chip, then connected to an adjustable DC supply. After some unsuccessful tries, I managed. Set to 5v initially for id check, set to 12v then erased, back to 5v to blank check, then 12v for...
  20. R

    29F032 protection permanent ?

    This is a bit beyond my skills =O But anyway, looking at that, it seems that locking is definitive and I don't have the temp unlock option in either programers I have at hand (top3000 and gq-4x4). It is present in the gq but it's greyed. Oh well, learning I guess. so if you plan on reusing...
Back
Top