I've been stuck on this for a while. I'm following a simple tutorial for RPi-controlled LEDs. From this, my LEDs do random stuff and don't light up correctly. I've been trying strandtest from this library's examples

Compare that to using Arduino Uno with FastLED's examples. Everything works perfectly with Arduino.

I know that this question is vague, but it seems like it scares people off when I ask this question in a more specific way with a more detailed explanation about my setup.

I've tried RPi 2 B+ with Raspbian Stretch and RPi 3 B+ with Raspberry Pi OS from January 2021. Same exact result with both RPis.

Any ideas what's going wrong here?

  • Is the LED strip a 5V strip? Are you powering it separately? – Jaromanda X Mar 31 at 5:30
  • If you are referring to NeoPixel type devices they DO NOT use PWM on either platform! (They use PCM.) It is possible to use the WS2812 with a suitable library on the Pi BUT you need a level shifter to get sufficient drive. I have used strandtest in the past, but the Adafruit code keeps changing - so I can't confirm current code. – Milliways Mar 31 at 5:38
  • It is a 5V strip with 150 LEDs that I am powering separately with a 5V 10A supply. --- This is the LED strip that I am using: ALITOVE 16.4ft WS2812B Individually Addressable LED Strip Light 5050 RGB SMD 150 Pixels Dream Color Waterproof IP67 Black PCB 5V DC --- I am using this level shifter https://cdn-shop.adafruit.com/product-files/1787/1787AHC125.pdf, which is recommended by Adafruit – errolflynn Apr 1 at 3:23

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