CyberCertPrepOT Security FundamentalsOT Fundamentals: Network Architecture & ProtocolsMEDIUMFree question
A PLC manual lists tank level at register 30001 and pump setpoint at 40001. Which Modbus tables does that numbering conventionally identify?
- A.Input registers for the level and holding registers for the setpoint
- B.Discrete inputs for the tank level and input registers for the pump setpoint
- C.Coils for the tank level and discrete inputs for the pump setpoint
- D.Holding registers for the tank level and coils for the pump setpoint
Why A is correct
By convention 0xxxx maps to coils, 1xxxx to discrete inputs, 3xxxx to input registers (read-only analog values), and 4xxxx to holding registers (read and write). A level sensor is naturally an input register and a setpoint a holding register.
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