AVerDi posted a topic in MitsubishiHi community, i need help .... I want to connect my HMI GOT 1455 to a PLC OMRON CP2MC by RS-232, but i cant do it. I'm using the following connection: HMI GOT1455 - PLC CPM2C (Interfaz CS1W-CN118) 2 (RX) - 2 (TX) 3 (TX) - 3 (RX) 5 (SG) - 9 (SG) - 4 (RTS) - 5 (CTS) * PIN 4 (RTS) IS CONNECTED WITH PIN 5 (CTS) In the HMI I configurated driver OMRON SYSMAC, CHANNEL 2 RS-232, TRANSMISSION SPEED 19.200, DATA BIT 7, STOP BIT 2, PARITY EVEN. But with all of that I can't connect both devices. In the PLC i can see the led COMM blinking, so it should have communication, but the HMI show me "Communication error. Refer to System Alarm in Utility Menu"