Hello! I have a problem with our A2NCPU it does not communicate to PC anymore, when I about to upload the medoc program by using cable RS422, it says that "no reply from PLC-system", I'm just wondering why the plc port cannot communicate anymore? is there a way to repair the communication port of A2NCPU? I suspect that when I connected the MAC50 display to the PLC, it caused the damaged of the PLC's port, assuming the communication is damaged already, is there anyway to repair it? what is the alternative solution for this in order to load the medoc program project? please help me. your response is higly appreciated. thank you.