Where can I find good information about maximum lengths supported? I found a good basic introduction, this doesn't mention lengths though.
I would like to use RGB, that would be four pins. However if I use 5050 RGB leds with a WS2812 I can drive them as SPI, needing just one wire.
What do you suggest for protocol? I had a string of led lights that uses TTL levels for distances of 30cm between (20 lights). Or do I need something like RS485 (but that requires an extra IC)?
Luckily someone has provided support for the software i2c library.