Neopixels every so often invert colors Moderators: adafruit_support_bill, adafruit

[figgyb]

I made an airport weather map similar to this one: https://pplaviationuk.wordpress.com/creating-a-metar-map/
but using MiniPCB neopixels to make them sit flatter. I've use the same quad-level shifter to up the PiZeroW GPIO to 5v and everything seem to be mostly working ok, except maybe once every hour or so the colors on the pixels get lit inverted.

Here is my code: https://github.com/gfbarros/metarmap/blob/master/metar.py

Again, everything works fine, I update the pixels once per minute, but maybe once every hour when they update they light up with the colors mixed up.
I also noticed that sometimes when the pixels update, they flash once or twice after lighting up.
I have also tried auto_write=False mode and get the same problem.

Any ideas?

[oesterle]

Hi, figgyb!

This looks like a fun project.

Can you show sharp pictures of your wiring? (800x600 works well.) Have you connected all your grounds together?

How many pixels are in the string? What power supply are you using, and what is its rated current in amps? What gauge of wire are you using between the pixels? At maximum brightness, RGB NeoPixels can use up to 60mA each.

It's a good idea, especially for runs of more than a few NeoPixels, to use the capacitor and resistor recommended in Basic Connections section of the NeoPixel Überguide. These help protect the pixels from spikes on the data line and brownouts on the power rail.

Cheers,

Eric

[figgyb]

Hi Eric,

Sorry, I already potted the board so can't get you a picture :( I could re-make the breadboard to show you but it looks exactly like the one on the website.

I have not used the resistor/capacitor, I'll add the cap right away and see if it makes a difference. If not I'll break it down and add the resistor to see if it helps.
I'm using this 5v 10A PS connected right at the middle of the string of LEDs:
https://www.amazon.com/gp/product/B01M0 ... UTF8&psc=1
I'm using 20AWG wire between the LEDs, there are 70 of them.

Thanks!

[figgyb]

ok, added the cap and will keep an eye on it. Thanks.