I have a Raspberry Pi 3 model B. I was using a 5.25V 2A power supply that I used for my previous Pi 2 (which made the red light flash because it didn't provide enough power) until last week, when the SD card got corrupted. At this point I bought a new power supply, the official one to be precise, which is 5.1V 2.5A. The red light flashing has stopped, which is good, although I have a very annoying usb 1-1-port2: over-current change message.

Anyway, here's my problem. If I use the old adapter, my Sense HAT seems to work perfectly: it displays the rainbow, turns off after a while and I'm able to control the LEDs with no problem. However, if I use the new one, a number of things happen:

  • The rainbow does not disappear. A few of the pixels do, though, which is strange.
  • If I clear the LED matrix (using the clear() function from the sense_hat Python module), a few pixels are left red. Clearing multiple times seems to actually clear everything.
  • The get_pixels function incorrectly reports that every pixel is black.
  • Anything else I do with the matrix seems to start by not working and begins to work after some time (a few updates): Printing rainbows, single pixels, clearing... anything.

I really don't understand anything. The only difference is the power supply, everything else is the same: same RPi, same SD, same Sense HAT, same code. Could the difference in voltage/current be the cause? If so, is there any way I can fix it?

  • What is plugged into the USB ports of the Pi. That what the overcharge message is about and they may well be related. You also do not mention if you rewrote the image to your SD card or replaced it. – Steve Robillard Mar 7 '17 at 21:26
  • @SteveRobillard Nothing is plugged in, only the Sense HAT and the power supply. The SD card is the same one but reformatted. – Darkhogg Mar 7 '17 at 22:14

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