Display Power Problems

Published on 2017-06-23 in Ye Olde Nowt.

As I’m getting more of it to work and testing with Pico8, I’m starting to see that I have a serious problem with the display. As soon as there are white vertical lines on it, it starts making high-pitched noises and do “tv noise” for some frames, and then the whole Raspberry Pi hangs.

Looking at the schematic, I think I made a big mistake connecting the display’s power to pi’s 3.3V pin. Sure, the display can run both on 3.3V and 5V, and since there is no communication from the display to the pi, there is no problem with voltage incompatibility. I suspect that this display takes a bit too much juice for the pi’s regulator.

The solution? I will try to un-solder the VCC pin of the display, and use a wire to connect it to the 5V pins. We will see how that works. One downside is that won’t look so good anymore.

If that doesn’t help, there is one more possibility – the display drivers in the kernel may be simply buggy, sending to the display some weird commands that trip it up.