Communication to Mitsubishi PLC using MC Protocol/ SLMP

Hi, does anyone have any experience or examples of reading and writing variables to a Mitsubishi PLC using SLMP protocol?

Hi Ben,

I’m no familiarized with MC Protocol, but I don’t think B&R support it. At least, I didn’t find any documentation of it in Automation Studio Help.

Probably you would need to find another compatible protocol to make this communication. You can find an overview of B&R supported fieldbus protocols in this post: Communication Protocol Devices - Share Info & Ideas - B&R Community (

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Hi Ben,

I’ve developed an MC protocol library, though it’s not actively supported at the moment. However, feel free to utilize it as a foundation should you require additional functionalities.

Attached, you’ll find a sample project featuring the library, which has been tested with Mitsubishi Q and R CPUs.

The library supports two communication types:

Batch Read/Write:

This mode allows for reading/writing a block of data, with a maximum size of 960 WORD.

Random Read/Write:

This mode allows for reading/writing multiple variables from different memory areas, with a maximum of 192 WORD.

By default, all communication is set to read-only. However, if you enable the option auto_write = 1, the mapping.Values will be monitored. Any changes initiated from the B&R side will automatically be written to the Mitsubishi PLC. (169.0 KB)


Hi @lukas.emersberger, it would be cool to add this to our GITHub with a short documentation, what do you think about it?

Hi @kovarj, that sound good! I also have an Omron FINS library that I’ve developed that could be shared.


if you are open to share it with us your solution with source files, it would be really great, that is what is community about :slight_smile:

Great thankyou, this is exactly what I am looking for!

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