XianXi
Member
Working on a Hook PCB with a weird problem.
Upon firing it up it boots normally then when it gets to the attract mode it makes it seem like someone is playing with the monitor voltage.
I don't think it's the sync as the picture pincushions like someone flipping the monitor off then it comes back and does it randomly.
Traced the sync back to a resistor pack which tested fine (100ohms per in/out) then from there it goes to the upper board to a custom QFP. I checked the resistors on the QFP and all are the same 250ohm. Roms all check out and are flashing normally.
Does the QFP generate the Sync signal itself?
Upon firing it up it boots normally then when it gets to the attract mode it makes it seem like someone is playing with the monitor voltage.
I don't think it's the sync as the picture pincushions like someone flipping the monitor off then it comes back and does it randomly.
Traced the sync back to a resistor pack which tested fine (100ohms per in/out) then from there it goes to the upper board to a custom QFP. I checked the resistors on the QFP and all are the same 250ohm. Roms all check out and are flashing normally.
Does the QFP generate the Sync signal itself?