Question: I would like to control the RTS line of the DS independently of the data sent over the port. I set the DS to:
This way I can control the RTS line by RTS of virtual serial port - it works fine until I send data over serial port. At that time the RTS line goes ACTIVE. Why is that? How can I set the DS to independently control the RTS line?
Answer: Yes, you can control RTS line remotely when FLOW CONTROL is DISABLED/REMOTE. However, this is still RTS line and it has some RTS-related behavior. Even when the FLOW control is off RTS goes ACTIVE when the serial port is opened and INACTIVE when the serial port is closed. This is done to emulate real COMs which often have the same behavior. So, you can still control the RTS line by sending commands but the line will also switch automatically whenever the serial port is opened/closed.
Now, if you want to avoid this then make the port opened at all times. How? Set the ROUTING MODE of the DS202 to SERVER/CLIENT. Right now, your routing mode is SERVER. This means that the DS202 waits for the PC (remote host) to establish connection. Before this happens the serial port is closed and RTS is INACTIVE. Once connection is established the serial port is opened and RTS becomes ACTIVE. When you send the data from the PC you are establishing a connection and this opens the serial port of the DS202 and this toggles RTS.
With SERVER/CLIENT routing mode the serial port is always opened. RTS is switched to ACTIVE after the DS202 boots up and remains in this state throughout device operation- unless you change the state by using PSx command.
Bottom line: use SERVER/CLIENT mode and RTS won't be toggeled automatically when connection is opened/closed.
