I've scoured the forums here and elsewhere and can't exactly figure out what my next step should be. I've followed this tutorial


exactly. My PI is wired up to a single led strip that I cut off the front of the ws2801 strip. I have it hooked up to a 5v 10a supply, and everything is wired as it is in the tutorial. I can't get the led to light up, and I was wondering how I should proceed from here to determine where the problem is.

Thank you,


Edit: RPI 3b, the LED strip is this one:


  • 1
    You should tell us WHAT YOU DID - not "followed this tutorial". Incidentally I would be sceptical of a tutorial whose author can't connect his multimeter correctly. Have you enabled SPI?
    – Milliways
    Feb 11 '18 at 0:38
  • 1
    I connected the ground on the pi, the ground on the power supply, and the ground of the strip. I connected the +5v of the strip to the power supply. I connected MOSI to the data input of the strip and the CLK to the clock input of the strip. I enabled SPI in raspi-config, installed spidev, and ran multiple (from separate sources) python scripts that theoretically should have caused at least something to happen in the LED strip. Nothing is lighting up.
    – B. Barkley
    Feb 13 '18 at 16:33
  • Have you checked to make sure the LED strip is wired on the correct end? Just a thought sometimes things like this get over looked. LED have diodes, and Diodes only allow the flow of current in one direction. Check the back of the strip to see if there is an arrow that tells you the direction of flow. Low of LED strips will have this. You may already have all this in check. Have you tested the strip on a more basic application, like on a micro-controller free from system processing interruptions? Just to rule out a faulty strip.
    – mrSidX
    Aug 9 '19 at 14:33

Are your 'data'-ground lines grounded to the controller device? This will need to be connected to the controllers ground to maintain a sync. Also, the RPi pins are running on software that is waiting to be called, and could cause data sync issues with that type of hardware, that needs to maintain proper sync to display correctly. There is a method to use the Pi's DMA that bypasses this sync issue through the hardware, but I get glitchy issues most of the time straight on the pi... I often find it easier to use an arduino type based controller, and have the pi send msgs to that to then translate to the controller to perform. I like the Huzzah Feather end ESP8266 a lot for this application of LED strips.

  • The Pi is wired like this diagram: tutorials-raspberrypi.de/wp-content/uploads/… The power supply, pi, and strip all share ground, the +5v of the strip is only connected to the +5 of the power supply. MOSI goes to data on the strip, and CLK goes to the strip's clock in
    – B. Barkley
    Feb 13 '18 at 16:35

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