Are you trying to load another overlay along with the CBB-Serial overlay? If you have the cape-CBB-Serial-r01.dtbo overlay in /lib/firmware and boot with the cape attached everything should already be muxed properly, and you should be able to use UART4 (/dev/ttyO4) for RS485.
The only RS485 connection point on the cape is the screw terminals, so you should just run a twisted pair of wires from an RS485 device to the connections on the terminal block labeled RS485A and RS485B. On Monday, July 21, 2014 6:23:18 PM UTC-4, [email protected] wrote: > > Hello all, > I have two questions below. And please help. > > 1. I add a RS323/RS485 Serial Cap from Logic Supply to my BBB. > After I configured the rs485 cap, pinmux shows that the UART is connected > to pins 28 and 29. (Pin 28 is pin 44e10870). > But when I check the kernel log, I have Error -22 saying that pin 44e10870 > is already requested by pin 481a8000. > > 2. How do I test RS485 function? And what interface cable do I need? > > Any ideas? > > Best Regards. > > > -Paul > > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
