Blinkt occasional glitches with RPi3

I just recently got an RPi3, and with it the Blinkt! LED bar. Plugged it in and installed the software and ran some examples. Everything is going great except that occasionally a LED will randomly briefly turn light blue (this is happening during the larson.py example), and I am unable to pinpoint a specific series of events that is causing it. I have the RPi3 connected to a TV via HDMI, in the USB I have a keyboard, mouse, and webcam, and I am connecting a PSMove via Bluetooth for PSMoveAPI.

I guess before I dive too far in to it, I should just ask, are occasional glitches normal/expected and something I should live with, OR are they a sign of something wrong in the lower level code that I should try to debug? Is it possible to read the color of an LED?

Thanks.

I can’t say I have seen, or seen reports that I could connect your issue with. Is it always the same pixel that gets this tint?

but to answer your closing question, Blinkt is a write-only device, so, no you can’t probe for a pixel state. It uses GPIO on bcm23 and bcm24, as long as you don’t use those you should get glitch free operation.

I’ve seen effects like that when Blinkt is running over jumper cables with a poor (power) connection. Not sure what to suggest if you’ve got it seated directly on top of Pi though…

It is not always the same pixel, I am not using the GPIO pins for anything else, and it is directly seated. If I’m not doing anything else with the Pi, it very rarely exhibits the behavior, but if I am interacting via keyboard/mouse or bluetooth controller, it happens maybe once every 20 - 40 seconds.

as per @major_tomm’s suggestion, it could be power related - what PSU are you using?

Sometimes random environmental noise can have this effect, but it should not persist for more than a fraction of a second since the Pi should be constantly refreshing the Blinkt.

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I am seeing this problem too. Random lights after
LED.clear()
LED.show()

  • Using a Pi 3B+ with latest Buster.
  • PSU is 3A brand new.
  • Blinkt is definitely well connected (it was hard to push it into the header)
  • Same Blinkt wasn’t doing that in my Pi Zero W – same code
    Suggestions?