(0x2B / 0x0E) Read Device Identification

[zorxd]

Hi

I need the function "Read Device Identification". It is a sub-function of the more generic "Encapsulated Interface Transport" (function code 0x2B).

I implemented a small patch to libmodbus that fulfills my needs. However it isn't a complete implementation of the function code 0x2B. Therefore I wonder if it's worthy enough for inclusion in this project.

[Kwarf]

Hi,

I also need this function. I have looked a bit in the code and it doesn't seem that easy to implement since the response does not have a data length field, so I'm guessing you would have to read to object count and then read all objects to know the frame length and then calculate the CRC.

Do you have your patch available anywhere public? I didn't find any fork on your account, it would be nice if you could share your changes.

[zorxd]

Hi Kwarf

My patch is limited, it only works for a single object at a time, and a single subfunction code: read device ID.

However you can see my changes in this repo: https://github.com/zorxd/libmodbus/tree/master/src

bye

[Kwarf]

Thanks, I pulled your changes into my own branch and did some more work on it. It can now read one or multiple device ID fields, however I'm not sure that it's the best possible solution so I won't open a pull request for it. It's available in https://github.com/eKontroll/libmodbus/tree/wip-read-device-id if anyone is interested.

[karlp]

I'd like something like this too, so as not to have to carry a local libmodbus, I've done what I needed in the user side, but it's not real pretty.

[stephane]

My very limited wip too is https://github.com/stephane/libmodbus/tree/read-device-id