[Hudson] is looking to drive a lot of LEDs. A driver that effectively addresses kilometers worth of LED strips isn’t an easy thing to come by. So he’s in the process of designing his own BeagleBone Cape to do the work. Above you can see the board layout he’s working with. Notice the set of repeating red footprints in the center? Those are pads for 32 RS485 connectors!
Of course this is all in preparation for Burning Man where the mantra seems to be: he who has the most LEDs wins. Well, unless you’re the sort that likes to work with flames. But we digress. The scaling problem that [Hudson] is dealing with hinges around his desire not to include ridiculous numbers microcontrollers and the need to beef up the 3.3V logic levels of the BeagleBone to travel further on the data bus of the strips. By leveraging the RS485 protocol — which is designed to carry data over long distances — he can get away with a single processing unit by adding an RS485 translator at each remote strip connector. He plans to use the BeagleBone’s Programmable Realtime Units feature to address the eight drivers on the cape. But first he has to solve what looks like a doozy of a trace routing problem