Hello everyone,
I'm repairing an SNK Neo Geo MVS MV2 motherboard.
The board previously had a paddle circuit issue, which has now been resolved. It now passes all BIOS diagnostic tests, including the paddle/video RAM tests, but still freezes on the grid screen when cartridges are inserted.
Current situation:
* BIOS diagnostics: All tests passed
* Palette issue: Fixed
* The board boots and displays the grid screen
* Cartridges are not detected/booted
* Using UniBIOS Memory Viewer, I'd like to check the cartridge header at address `0x000100` where `NEO-GEO` should appear.
* I suspect a problem with the cartridge's PROG bus, likely on the address/data lines between the slot and the NEO-G0, or a broken track/via.
I'd like some more experienced people to share how to troubleshoot this issue. From what I understand, the management of the signals to the slots should be driven by the neo g0 at position 2.5. Thanks for any advice.
I'm repairing an SNK Neo Geo MVS MV2 motherboard.
The board previously had a paddle circuit issue, which has now been resolved. It now passes all BIOS diagnostic tests, including the paddle/video RAM tests, but still freezes on the grid screen when cartridges are inserted.
Current situation:
* BIOS diagnostics: All tests passed
* Palette issue: Fixed
* The board boots and displays the grid screen
* Cartridges are not detected/booted
* Using UniBIOS Memory Viewer, I'd like to check the cartridge header at address `0x000100` where `NEO-GEO` should appear.
* I suspect a problem with the cartridge's PROG bus, likely on the address/data lines between the slot and the NEO-G0, or a broken track/via.
I'd like some more experienced people to share how to troubleshoot this issue. From what I understand, the management of the signals to the slots should be driven by the neo g0 at position 2.5. Thanks for any advice.