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I am trying to connect a Panel PC (Bartec RS-422) and an Omron PLC (CJ2H RS-232) I am using a Kinematics 2199 RS232 to RS422 converter. Results: Testing software Multiway v9.5 1) Using a usb to rs-232 cable on another PC     - I am able to send and receive a hostlink commands between the panel rs-422 converter and the PC rs-232. commands come through correctly 2) Using the PC to connect to the PLC     - If I connect directly to the PLC using the usb to serial cable and a short adapter I made to map the Omron PLC pin out 2-2,3-3, 5-9, I can send and receive hostlink commands to the PLC. Everything works as expected 3) Using the Panel and the USB Cable    - If I connect the usb converter to the Panel I am also able to communicate with the PLC 4) using the RS-422 port on the Panel     - If I connect the panel RS-422 port and converter and then connect to the PLC. I can only send commands; I cannot get any responses come through from the PLC. My converter box has LEDs on the RX and TX channels and I can see the PLC tries to send something. But something must be corrupted as multiway does not show and response.  I have tried a bunch of things but I am at a loss on how to diagnose this issue. Since I can get the two PCs talking to each other sending and receiving, I can rule out any wiring issue between the converter box and Panel.  Since I can plug the USB into the Panel and get it to work correctly, I can rule out any operating system issues and PLC configuration issues. The only link I cannot verify is that from the converter box to the PLC, I am not sure if the PLC can push hostlink data that has not been requested.  I have no idea why I can write to the PLC but not read. If anyone can provide any insights, I would greatly appreciate it, It has been two days and I am stuck. I am looking at maybe getting a logic analyzer to try and see what the PLC is sending back, but that will be months away.  I am happy to try any suggestions