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CMB27 / ModbusRTUSlave

This is an Arduino library that implements the slave/server logic of the Modbus RTU protocol.
MIT License
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How do I know which ModBus register was written lastly? #28

Closed F1schi closed 9 months ago

F1schi commented 9 months ago

First of all: Thank you for providing such a great ModBus-RTU library!

My issue: I would like to get to know in my code, when a register was written in order to respond to the new "parameter" (in my case) due to the fact that the Arduino serves as a data translator between different protocols. Is there already a possibility to get to know the register type as well as the register ID?

(I used Version 1 where it was possible, but I would like to upgrade to the newest version of the library)

CMB27 commented 9 months ago

No, there is not a way to know which registers are being accessed by the master device with this library. That was one of the compromises I made for better ease of use in version 2. I figured that for more specialized use cases, this library could be used as a staring point.

You could make duplicate arrays, one that the library writes to, and one to compare to, in order to detect changes, but this is not very memory efficient.

I recommend you make a copy of the latest version of this library and modify it to suit your needs.

F1schi commented 9 months ago

Thank you for the quick response!

Is this library still under construction and are you planning to implement such a feature or is this the final version of the library?

I also had the problem with the old version (I haven’t tried the new version) that the response message which should be sent by the library, wasn’t correct or missing. For this problem I sent my own response – is this a known issue?

CMB27 commented 9 months ago

At present, there is no ongoing work on this library other than debugging. There are no plans to implement such a feature. Whether or not this is the final version of the library remains to be seen.

I have not heard of this being an issue with the current version of the library.

F1schi commented 9 months ago

Could be a feature with great potential.

I will have a closer look at the response messages in a few weeks.