This is again not FastLED related but still VERY LED related.

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This is again not FastLED related but still VERY LED related. I put up a small guide on how to use a Raspberry PI to drive APA102 Pixels using C++. I have previously been doing this on my larger projects using NodeJS and the MRAA library for SPI, but have run into bottlenecks.
Here is the GitHub with the simple Driver code https://github.com/leonyuhanov/rpi_apa102driver it’s designed to drive 144 pixels for the demo. And here is the tutorial http://www.elec-tron.org/?page_id=1296 it describes how to wire everything up and how to install the apropriate libraries. I’m using the BCM2835 library.

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I’m curious why that first pixel needs to be powered separately by 5V from the Pi?

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@marmil It does not really need to be powered by the Rpis +5v but its easier to put 1 4 pin cable into the Rpi box -> http://http://www.elec-tron.org/wp-content/uploads/2016/03/20160302_110922-1.jpg

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@marmil That’s a “ghost pixel”. It’s a signal repeater that, because of its short connection, have no problem reading the 3.3V signal from the Pi, but will output a 5V signal from the other end. In this case, it’s being used as a level shifter.