User Documentation

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device ID. This kind of mapping allows a unique addressing of serial RTU/ASCII and Modbus TCP
devices having the same real device ID.
Example 1:
Default Slave ID Map for RTU/ASCII slaves connected to the serial port. By default there is direct
assignment between virtual and public accessible device ID and real device ID (without any offset).
Example 2:
In this example a Modbus TCP Master can address its slave devices (via the Modbus gateway) as
follows:
10 Modbus RTU/ASCII slaves connected to the serial port by virtual 1 to 10. The
the same.
1 Modbus TCP slave with IP 192.168.1.111 (Port 502) by virtual device ID 11. The real device
ID is 1
1 Modbus TCP slave with IP 192.168.1.112 (Port 502) by virtual device ID 12. The real device
ID is 1
Parameter
settings resulting
D
as shown
above
Note:
The Modbus Gateway will disregard any request that is not addressed to an existing virtual slave ID on
its slave ID map. If a real device ID has not been assigned to a public virtual slave ID, it will not be
accessible by masters on the other side of the Modbus gateway.