PanelDue M408, M20, M36

[thinkyhead]

As requested in #10609

Add support for the PanelDue touch controller by Escher3D and the M408 command it requires.

• M20 still needs work to add the P parameter for selecting a folder and for printing long filenames. The existing implementation just prints the whole directory with full DOS 8.3 paths.
• M36 still needs to be implemented. The M27 C command is similar, so part of that code can be re-used.

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A test unit is on the way!

[bwgeez02]

Did you receive the test panel?

[thinkyhead]

It arrived yesterday, along with the 4-pin connector, thanks! I'll hook it up to something and get into testing this weekend. I haven't read the online docs yet, but I'll do that tomorrow to see what it can do and how it connects to the board.

[SHAWNLC]

Are you still working on this Paneldue fork? Github kinda confuses me at times. https://github.com/MarlinFirmware/Marlin/actions/runs/4727590705/workflow

[oliof]

Just a heads up that future versions of the PanelDue firmware will stop using M408 and switch to M409 https://forum.duet3d.com/topic/34386/advance-warning-removal-of-m408-command-and-rr_status

[thisiskeithb]

David's comment was buried in all the force-pushes: #10610 (comment)

I can provide a list of the M409 values that PanelDue uses if that would be helpful.

[dc42]

Just a heads up that future versions of the PanelDue firmware will stop using M408 and switch to M409 https://forum.duet3d.com/topic/34386/advance-warning-removal-of-m408-command-and-rr_status

PanelDueFirmware has been using M409 for a long time now, about two years I think.

[dc42]

FYI we are working on a replacement for PanelDue that will provide better graphics capabilities and a more easily customised UI. It will use M409 in the same way that more recent versions of PanelDueFirmware do.