Previously we used enable the UART ports by hand, but that’s annoying because it required doing it manually every time the BBB boot. In addition, writing a script wouldn’t work for some reason. For my quadcopter project, the BBB must enable all UART ports by itself at boot, since I can’t fly with a wire hooked onto it. Therefore, I went on and do some digging on this… took a while before anything came up. It’s actually more complicated than I though, having to deal with how device tree works and all… but here’s what I found:
In order to use the built-in UART pins on the Beaglebone Black, we must first activate it.
The device name and pins is as follow:
Credit – http://beaglebone.cameon.net/home/serial-ports-uart
|UART0||J1_4||J1_5||/dev/ttyO0||BeagleBone Black only|