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How can I read %I/Q or %M on my M221 M241 M251 M258 LMC058 using Modbus ?

2 cases have to be considered: M221 or (M241 M251 M258 LMC058).

M221 :

%M (internal bits) can be accessed using function codes from the table below (extracted from SoMachine Basic online help).
Note that %I (physical inputs) and %Q (physical outputs) can not be accessed directly by Modbus.



M241 M251 M258 LMC058:

%M (internal bits) can not be accessed by Modbus.
But %I (physical inputs) and %Q (physical outputs) can be accessed using function codes from the table below (extracted from SoMachine online help).

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