How does the grid editor identify the source device of a MIDI message?

I did not dive fully into the current implementation of Editor's midi monitor, but it has two separate parts: one true midi monitor, which checks midi through MIDI port and the other one is debug midi, which is parsed from the serial data coming to Editor from the hardware. There the data has the x-y coordinate among other details.

To see the x-y coordinates, flick over the toggle top right on midi monitor.

Do you want your PBF4 units to send the same data no matter their positioning?
To some extent, you will have to go over all elements manually once to change them.

For example this example on the image fixes channel ch and calculates num from the element index. You could add a multiplication to the num or ch based on module position X / Y or an arbitrary number as a global variable to avoid clashing with multiple MIDI controllers and their midi values.

Ah yeah, so maybe I can just connect to the device via webserial and use the serial messages instead, like the editor does?

I admit my use case is a little odd - but I don't really want to configure the device via the UI, just programmatically as much as possible. It's for a webapp where I'd like people to be able to purchase the grid hardware modules and use them with it out of the box, without needing to configure them first.

Do you know if the serial protocol is published anywhere?

If you feel more comfortable that way, yes, but you would have to do immerse amount of legwork in my opinion.

I'm ok with that - I'm the author of the loupedeck NPM package and had to reverse engineer its serial protocol. But it would be nice if the Grid serial protocol had some docs that could be shared?

There are no special docs other than the reference / wiki pages of the docs.intech.studio.

https://github.com/intechstudio/grid-protocol/blob/master/src/grid_protocol_bot.json

These are the protocols descriptors used in Editor.

https://github.com/intechstudio/grid-editor/blob/stable/src/renderer/runtime/runtime.ts
this is the runtime in editor which does quite some heavy lifting in parsing and using the data from pthe hardware

And there is the message stream file which might be interesting for you, where the data coming from hardware is used in the editor.

https://github.com/intechstudio/grid-editor/tree/stable/src/renderer/serialport

that's super useful! I had not actually read any of the grid editor repo code yet, this helps a lot to narrow it down 😁

I am not knowledgeable enough in the firmware part though, but grid-fw repo is your option there.

Although our code could be better as this is our first hefty code base and has some skeletons in there, I think with the help of Claude / Gemini or other llm, you should be able to get a general understanding in how things work.

No codebase is immune from skeletons, that's just the nature of software 🙂

Really appreciate your time on answering my questions, thank you!