TFT GCode visualization

For my powder bed printer, I find it useful to have an on-board visualization system of the model that has been rendered under the powder.

I think this might be generally useful. I used the Adafruit ST7735 for my project, but the codebase should be readily adaptable to any full color TFT.

Time lapse video of the visualization system running:

[youtu.be]

And before you ask, yes, that is a 3D projection with Z shading on an Arduino Mega 2560.

GitHub link to primary code checking: (GPLv2)

[github.com]

That looks good! How much code and data space does the visualisation software take up? I'm currently having 100 TFT 3D printer control panels manufactured (see [forums.reprap.org]) and the existing firmware for the ATSAM3S2 processor leaves around 80K free code space and 14K free data space. So I'm wondering whether I may be able to add your visualisation code.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I'll do an analysis in a bit (I have a STM32 I can try it on) but off the cuff that should be much more than enough code/data space.

For your panel, what printer firmware is it expecting to talk to?

The firmware for your panel seems to assume a JSON reply format (which I would like to use in my powder bed printer), but I don't see that documented anywhere.

It talks to my fork of RepRapPro firmware for Duet electronics. The message format is documented at [reprap.org], specifically the extensions to the M105 and M20 commands and the M36 command. I am planning some minor changes to the M105 responses prior to releasing the first batch of boards. It is based on the format used by the web interface to the Duet, except that the commands are gcodes instead of http request types.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Ah, M105 only. Now it all makes sense.

For a point of reference, an unoptimized sketch with just the visualization support (null axes, no SD card) clocks in at approx 28K flash, 3K ram.

I should be able to squeeze that onto a Atmega328P device (Arduino UNO), and hang it off the TFT as a GCode pass-through device.

If I get that working, would anyone be interested in something like that as a Rep-Rap add-on?

(You'd plug it between your computer and the reprap, and it visualizes what your reprap is supposed to be doing).