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Modbus FC code
#1
Hi,
I am communicating to a Wago PLC 750/881 in Modbus TCP/IP. In the profile I use this following register:

{"name":"Proportional","bus_datatype":"14","datatype":"float32","type":"inputregister","address":13535,"writable":"true"}

I can read value of the PLC but when I try to write to PLC nothing happen. I am thinking about "inputregister" which is FC04 code.

Probably I have to write to Wago using FC06 code but in the profile which type I have to use?

Thanks.
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#2
Hi
Change type to register
BR
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#3
Hi, I changed it to register but there is something strange.
I mean that variable was read (value was 100) but after a while value has gone to 0 but without writing.
Strange behaviour.

What do you think?
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#4
(25.10.2018, 19:12)Domoticatorino Wrote: Hi, I changed it to register but there is something strange.
I mean that variable was read (value was 100) but after a while value has gone to 0 but without writing.
Strange behaviour.

What do you think?

Log this object and check where from this value came from. It doesn't need to be modbus. 
Are you able to check the value on your plc?
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#5
Hi, how can log this value? The only way is logging it on knx bus. Do you mean it?
I can check variable on plc side and in fact it has been not modified.
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#6
Just tick LOG and then in Object log when a value is received it will tell you the source.
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