Hello! I'm having trouble with my LED strip that I purchased from Aliexpress (link

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Some APA102 strips require a lower data rate as the length of your strip gets longer (I’m not sure why this is - I have a board with 768 APA102 leds that I can run at full speed) - you can change the speed by changing your addLeds line to:

FastLED.addLeds<APA102, DATA_PIN, CLOCK_PIN, GRB, DATA_RATE_MHZ(5)>(leds, NUM_LEDS);

(for example, that will push the spi data speed down to 5Mhz)

(also - make sure that you’re running the latest FastLED3.1 branch - the master branch has some incorrect frame issues around apa102’s)

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@Daniel_Garcia Oh my goodness that finally worked! I had to lower the data rate down to 1 (Mhz? Is that it?) for the strip to fully operate.

Thank you all for your support! I can’t wait to show off my project to this community.

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Ick, that’s too bad if you had to lower it all the way to 1Mhz. But great if you finally found something that made it stable!

You might experiment and put a 300 to 500 ohm resistor on the data line. Put it inline on the end of the data line just before the strip. (Do you think that might help here @Daniel_Garcia ? I’d love to find out why some setups play nice with higher data rates and others not so much.)

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@marmil no idea - this is an area of electronics that I’m weak in.

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I did some more testing and found that I’m able to raise it up to a max of 4Mhz. Any higher and the end of the strip (say, ~20 or so leds. About a less than a meter it seems) goes haywire as mentioned above. It’s a bit interesting to see why that happens.

@marmil , I’m actually trying out resistors on the line tonight! I initially thought it was a power issue, so I tried there. I haven’t thought about putting them on the data line. I’ll try it out and get back to you!

Again, thank you Marc and @Daniel_Garcia , and @01001101_01010111 for helping me out!