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i.CanDoIt® Guided Tour (p.17)
Modbus RTU Gateway
This set of pages will provide a brief overview of i.CanDoIt® features and functions. Cruise through using the Next and Previous buttons, or skip around using the links at the bottom of the pages.

The Mobus RTU gateway is a Modbus master, and can poll up to 50 slave devices. Its remote read and write capabilities are virtually identical to the TCP gateway.

The remote device "read rule" mainly says what remote register to read and where to put the data. But you have the option of scaling data as it comes in. You also have the option of applying a default value if the read fails.

The remote device "write rule" allows setting up a "send on delta" to only write the register to the remote device when the local data has changed. You can also send periodically, with optional data scaling on the way out.