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  1. ack

    Neo Geo MV1FZ garbage screen and no click of death

    Check the voltage on your 5V rail.
  2. ack

    AES 3-5 Palette RAM Unwritable

    R/W should be coming from the cpu, maybe you have a cut trace?
  3. ack

    AES 3-5 Palette RAM Unwritable

    PALWE would only go low on a write from the CPU. It might not happen that often. Reading nothing on 40 sounds like the problem. Do you also get nothing from the WE pins on the palette ram chips?
  4. ack

    AES 3-5 Palette RAM Unwritable

    I would work your way back to where the WE signal comes from / generated from. As you noted its coming from the NEO-G0 chip (pin 41). https://wiki.neogeodev.org/index.php?title=NEO-G0 If you look at the schematic picture it looks like pin 41 logic is based on the inputs from pins 39 and 40...
  5. ack

    MV4 repair attempt / PRO-B0 potentially dead

    Couple things I would try - Clear the backup ram - Verify the 5V rail is at 5.0V when the board is powered on with games in it.
  6. ack

    Neoboismasta

    Provide a link to what you bought. I would bet it comes with unibios if its already consolized for you.
  7. ack

    MV4 repair attempt / PRO-B0 potentially dead

    Good job I finding and fixing what you could. I would get the PRO-B0 swapped. Something in side of it got hot enough to rupture it so there is going to be internal damage. For the game crashing part, that may just be dirty slots or games edges connectors.
  8. ack

    MV1FZS And one cart problem

    There is definitely something wrong related to those ram chips. I'm a bit suspect its not the chips themselves, as it seems unlikely they would both have the same fault (returning 0x00 after the diag rom wrote 0x55). I would probably do these things - use logic probe to verify none of the...
  9. ack

    MV1FZS And one cart problem

    Yes those are the ones.
  10. ack

    MV1FZS And one cart problem

    The combination of those 2 diag bios errors points to neither ram chip being writable. I would check for activity on the WE pin on both of the 2K ram chips. You might just have a cut/damaged trace.
  11. ack

    Consolized MV-1B hw test failed

    https://wiki.neogeodev.org/index.php?title=NEO-GRC2 - check continuity between NEO-GRC2 D0-D15 to the CPU (I dont know off the top of my head if its a direct connection, so their might be a buffer in between) - check continuity between the NEO-GRC2 and the VRAM data pins (I think these must be...
  12. ack

    NEO-AES3-6 VRAM issues

    That diag error is saying there is something wrong with the upper 2k vram chip or one of the traces to it. https://github.com/jwestfall69/neogeo-diag-bios/blob/master/docs/ram_locations/neo-aes3.md https://wiki.neogeodev.org/index.php?title=LSPC2-A2 I would check continuity between F8-F15 pins...
  13. ack

    z80 error

    It could be either, or the z80's ram. However the first thing you should do is clean your cart's edge connector and the cart slot.
  14. ack

    Rengual's faulty MV4-FS & MV4-F

    For the MV4-FS I don't think it will have anything to do with the ZMC2, since that is specific to sprite data. The images show the issue is effecting both sprites and the fix layer. Additionally valid looking graphic data is being returned, its not the right ones. I would suspect an issue...
  15. ack

    Sound problem in MV1A

    Sounds like its the YM3016.
  16. ack

    MVS MV1FT not fully booting. Wrong graphics/letters

    could be. Another thing you can try is pressing down on different chips / parts of the board while its on and see if anything changes. If it does its an indication of a bad solder joint some where.
  17. ack

    MVS MV1FT not fully booting. Wrong graphics/letters

    warm is usually ok, to hot to touch is not.
  18. ack

    MVS MV1FT not fully booting. Wrong graphics/letters

    Try checking the 68k data pins going into the LSPC. Maybe there is something wrong with D8 (floating?)
  19. ack

    MVS MV1FT not fully booting. Wrong graphics/letters

    It would depend on whats being executed on the cpu. If its the diag bios its likely ok because it puts up the memory error then goes into a loop waiting for input.
  20. ack

    MVS MV1FT not fully booting. Wrong graphics/letters

    work ram wont cause that.
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