Excellent Videos about APA102c operation.
Ran across a couple videos by Julian Ilet showing experiments he did with APA102c leds.
Apologies if it’s old news, but I found them to be the most thorough (and simple) explanation of the quirks and inner workings of the APA102c.
Part 1 : (gets good around https://www.youtube.com/watch?v=UYvC-hukz-0&nohtml5=False&t=5m50s)
https://youtu.be/UYvC-hukz-0
Part 2 : https://youtu.be/i4qh1HFU9-s
https://www.youtube.com/watch?v=UYvC-hukz-0&nohtml5=False