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Figure 45 Monitor the Send/Receive Data
7. Modbus Advanced Function
The serial device server with Modbus Gateway function itself does not have the station
address and registers, it
’s a bridge of communication, and will produce Modbus RTU specify
appointment according to the Slave ID, function code, register number in the Modbus TCP
instructions which user software send to Modbus Gateway, and output from serial port. You
can see it as a
“Protocol Translator”.
7.1 Enable Modbus Gateway
First the serial device server should support Modbus Gateway as the
“Modbus TCP to
RTU
” function in the device supporting function of Table 5 device manage dialog box
should be selected.
By default, the serial device server is in the normal pass-through mode. If it needs to be
converted to Modbus gateway mode, please select "Modbus TCP<->RTU" in the
"Transfer Protocol". Since then, the device automatically changes the "port" parameter to
502 (the port of Modbus server).
The serial port RTU device is as slave, the host Modbus TCP software connects the 502
port of Modbus Gateway, and the Modbus Gateway need to work in TCP Server Mode; if