Configuring Flow Control on UART4

Hi there.

I am trying to configure the UART4 on the beaglebone black. I took the device tree source file from /lib/firmware for UART4 and added the necessary pins for RTS/CTS. This seemed to work, however in practice the BBB does not properly respond to RTS pulled high from the other device. Writes of “packets” complete, but any new writes do not continue. Attached file of scope capture shows my problem, where the BBB continues to send data.

Am I improperly configuring the UART? (I have disabled the HDMI cape). I have attached my dts and output from ‘cat /proc/tty/driver/OMAP-SERIAL’ below.

Kernel 3.8.13, Angstrom


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Got the same issue here.

Simple UART communication is OK, but I’m trying to use RTS and CTS too.