Hello!

I am using friendlycore-focal_4.14_armhf OS with NanoPi NEO Core board. I am going to connect the RS485 transmitter to the UART1. I have changed DTS to support RTS and CTS signals:

I have chenged "pinctrl-0 = <&uart1_pins>;" to "pinctrl-0 = <&uart1_pins>,<&uart1_rts_cts_pins>;" (viewtopic.php?f=37&t=3204&p=12286&hilit=RTS#p12286)

I am sending data via termios library, there is no activity at RTS pin. I have enabled the flag CRTSCTS, but it doesn't help.

When I send data from the command line:

echo "1" > /dev/ttyS1

I see RTS activity, but it works strangely: RTS goes low before the start bit (it is normal) but it goes high after the stop bit after ~15 ms!! Any suggestions, as to why RTS has the delay? Or, how I can configure UART for RS485 communication?

Thanks!