Alright, so I got myself into yet another project with a bakers dozen Dig Dug PCBs that I am going to repair and hopefully teach myself more about board repair along the way. I have a couple boards I am having issues with and would like a push in the right direction. My tools are limited to a soldering iron, a logic probe, GQ-4X Programmer, and a multimeter. I am testing all these boards in my Dig Dug cabinet which is putting out all the correct voltages. I'll put the DOA and likely time consuming boards aside and work on these four partially working ones first.
Board 1 passes ram and rom check but resets right after the crosshatch and never loads the game. Grounding the watchdog will keep the crosshatch on the screen and will allow me to coin up, but game does not play. Self test mode seems fully functional. FIXED: Bad 3rd Priority CPU
Board 2 resets after ram check and never checks the ROM. Grounding the watchdog will give a ROM B error, which does not make sense. Self test does not work.
Board 3 boots and gives ROM 1 error without the need to ground the watchdog. Tried known good ROM in the corresponding socket and the issue is not resolved. Self test does not work. Update: Several traces damaged while attempting to remove the socket. Ill put this one on the back burner for now.
Board 4 boots to squared colors (distorted sprites) and crosshatch screen is completely white, which is where it freezes. Cannot coin up or make out any graphics/text. Possible video processing issue?
Can you give me some pointers?
Board 1 passes ram and rom check but resets right after the crosshatch and never loads the game. Grounding the watchdog will keep the crosshatch on the screen and will allow me to coin up, but game does not play. Self test mode seems fully functional. FIXED: Bad 3rd Priority CPU
Board 2 resets after ram check and never checks the ROM. Grounding the watchdog will give a ROM B error, which does not make sense. Self test does not work.
Board 3 boots and gives ROM 1 error without the need to ground the watchdog. Tried known good ROM in the corresponding socket and the issue is not resolved. Self test does not work. Update: Several traces damaged while attempting to remove the socket. Ill put this one on the back burner for now.
Board 4 boots to squared colors (distorted sprites) and crosshatch screen is completely white, which is where it freezes. Cannot coin up or make out any graphics/text. Possible video processing issue?
Can you give me some pointers?
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