Worklog 5th GEN64 Assembly

[Cleetus_Buckwalter]

Well, I tested all of my connections with my DMM and they seemed fine. I then used a cheap oscilloscope and probed the video signal where the yellow wire is soldered to the driver board pin, and I got what looked like a signal.

I then wanted to test with a different display, but I didn't have another LCD and driver board.

So I got an idea...

Why not disconnect the video and ground wires from the driver board and solder them to an RCA cable, and then connect that RCA cable to a CRT?

I gave that a go and, sure enough, the signal seems to be fine.



So it seems like the problem is something to do with the driver board. I reseated the ribbon cable with no success.

Not sure what else to do...

I forgot to mention, I confirmed 5V going to the driver board with my DMM. I also made sure that the video pin on the driver board wasn't loose or disconnected from the board, itself.

 

[Cleetus_Buckwalter]

Finally got some time to troubleshoot.

When I supply 4.9V power to the driver board from my bench power supply, everything works great. Video shows up on the LCD screen every time I turn the system on, and the video quality is good.

When I try to power the driver board from the N64 PMS, I get a blue screen about 95% of the time. The other 5%, I'll get very noisy video for a few seconds, and then back to a blue screen. But my DMM is showing 4.9V at the power input pins for the driver board.

Everything else seems to be working correctly (audio, buttons, LEDs, charging).