Blinkt occasional glitches with RPi3


#1

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.


#2

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.


#3

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…


#4

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.


#5

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


#6

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.