Operation
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Figure 6.14
–
Modbus Master Aux Mapping
Next the data saved in the internal Modbus Register at MB Holding Register 3000 is mapped
to the ControlNet Scheduled Target connection input assembly with offset 50.
Figure 6.15
–
Internal Mapping from Modbus Register to ControlNet
NOTE:
The user will need to ensure that when writing to the ControlNet Router
Modbus Holding Registers that the registers holding data from the device are
not inadvertently overwritten.
6.6.
MODBUS TCP SLAVE
When the ControlNet Router has the Ethernet Mode set to Modbus TCP Slave, then the
ControlNet data can be mapped to and from configurable internal Modbus Registers and
offsets using the Internal Map.
The internal Modbus Registers can then be asynchronously exchanged with a remote Modbus
TCP Master. The remote Modbus Master can read or write to the configured Modbus
addresses to access the ControlNet data that has been mapped to the Modbus Registers.
In the example below the ControlNet Router, with the Ethernet Mode set to Modbus TCP
Slave, will have multiple Modbus Holding Registers written from a Modbus TCP Master and
then map the received data to ControlNet IO that is owned with a scheduled ControlNet
connection (when ControlNet mode is Originator).