I have a Micro820 connected via Modbus TCP. Connection is good and able to read Tags and inputs/outputs, but unable to write (error says unable to write to that node). Analogue writes are OK. I've checked all read/write settings and all look ok. Can't see why I should not be able to write Boolea…

Coils and Holding registers are readable and writable at the protocol level in Modbus. Discrete Inputs and Input Registers are only readable in Modbus. Use the latter if you do not want an external system to be able to write. Use the former if you do. That's it.

Unable to Write to PLC Tags (Read OK)

Ignition

pturmel January 19, 2023, 1:44pm 9

No longer true:

{ /shameless plug }

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