Modbus TCP/IP Send different function codes

[nick1365]

I would like to ask how can I sent different function codes to the system. For example I change the temperature in the demo, but the function codes are the same 1 and 3 from the modbus. From where can I change the function code values or how can I make the system send different ones ? Thank you for your time.

[Mikhail]

Modbus template editor http://doc.rapidscada.net/content/en/use-cases/modbus-protocol-files/modbus_template_en.png allows to change “Data table”. The function code depends on the selected item: Holding Registers, Coils, etc. You can see function code below the Data table combo box.

[nick1365]

Thank you for your prompt answer. But I have a question. The function codes that you have for example in the Max Temperature or Min or in the average are arbitrary ( so I can change with whatever function code I want or you follow a manual ? ). Thank you!!

[Mikhail]

Function codes are predefined by Modbus standard. Why do you need your own function code? What is the register map of your device?

[nick1365]

I do not need my own function codes, but I just need to make a scenario that uses different function codes (except of function code 1 and 3 that Max,Min avg temperature has). I need to construct some demo procedures that use function code 2,4,5,6,15 and 16 or just send some function codes manually (I know the sequence of function codes that one specific procedure has).

[Mikhail]

You can’t send function codes manually. You should configure Modbus template that uses the function codes you need.

[Author]

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