I have an industrial product (designed to view PLC data) that can communicate both ModbusTCP and Ethernet/IP.
This device was originally a ModbusRTU Master however, the manufacturer added a module to enable Modbus TCP.
The new module connects to the original serial port and is the SLAVE on the serial side. I believe it is then a Master/Client on the TCP side.
This device is designed to communicate with any PLC (programmable logic controller) having the Modbus TCP protocol.
The problem is that the device does not see data unless the PLC is polling or the data is changing in the PLC.
Also, there are no Device Configuration Parameters available such as “Timeout”, “Retries” and “Inactivity Timeout”.
Only within the PLC are there parameters related to the port for communication.
My question is…, since the PLC appears to do the polling, is it possible to have a CLIENT in the Modbus TCP world depend on the SERVER to poll before it will capture the data?
Thank you in advance,