Auto-detecting LED strip length (sometimes) Hackaday is featuring an article about how to auto-detect

Auto-detecting LED strip length (sometimes)
Hackaday is featuring an article about how to auto-detect LED strip length. Dan and I have mused about this possibility before; of course it only works well if the strip shares power rails with the Arduino, and if the power supply droops sufficiently – but still, this is a great hack and a fun idea to see executed.

Couldn’t you also detect the signal on the data-out end?

Yep. I think the article mentions that possibility, too.