Figure 15: Modbus Connection Rtu Screen; Figure 16: Modbus Connection Ip Screen - Unitronics GW-BAC1 User Manual

Unitronics's BACnet Gateway User Guide
Note that the read function will let you read and write while write function will only let you write.
Read and write block continuous means that the data will be read and write continuously.
Write block on change means that only when there is change in the data, it will be written.
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Modbus Connection: Here the user will configure the Modbus connection to the PLC.
First the user must select between Modbus protocol: RTU or TCP/IP, then the corresponding configuration.
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Figure 15: Modbus connection RTU Screen

Figure 16: Modbus connection IP Screen

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