I have a large shelf (like 5-10meters, or 15-30 feet long) which I want to put an LED in at every level. Thing like a positional system for a mini-library. I have a litte problem to efficiently drive the LED's. So I figured wiring every LED to the main board would be a waste of cable.
I think that I could make a mini LED-driver board per self part, and then daisy chain these drivers and let them be controlled from the main board.
LED - Main Board --- LED-Self-Driver1 --- LED-Shelf-Driver2 --- ... |- Shelf1, Row1 |- Shelf2, Row1 ... |- Shelf1, Row2 |- Shelf2, Row2 ... |- ... |- ...
A - or | should indicate the cable connection in the 'diagram' above. That would save me a lot of cable. :)
My question: What would be a good way to daisy chain these Arduino's? The space between the shelf parts (and the drivers) would be at most one meter and the chain connection should include the powering of the drivers. The connection speed should be around 1kbit's.
Would SPI do it? Maybe a Software SPI with slower frequency? How would you do it? Or is the connection scheme a stupid idea?
Thanks for reading and happy X-Mas :)