Every now and then after reboot (or power-on), RS232 port wakes up in a state, where it receives data, but cannot send any. Meaning, that no activity can be observed on pin 2 (RXD).
Our RS232 port is configured as Serial type Over-IP (TCP), mode Server.
The connection is made with three wires, GND, RXD and TXD. All the other pins are left unconnected.
Rebooting the device solves the problem, as after a few reboot cycles RS232 starts working as expected, but we are keen to find a solution without a need for reboot.
We are working with the latest firmware, RUT9XX_R_00.06.06.1.