I communicate the unitronics vision230 PLC through Ethernet , earlier I succeed to read and write the register using modbus Ethernet master query vi but currently I face the error 63 Tcp open connection problem. I check the Two PC communication through TCP and it has been communicated no error occur but when connect the cable to PLC it gives the error. Only open connection and close connection VIs are used to check. Same VIs are use only change the IP address and port number.
