Marlin inner workings, any experts?

[Mjolinor]

I have fitted a Ramps board to a laser cutter and modified Marlin reasonably sufficiently to get it operating.

My problem is the "over temperature" functions. I have a thermistor inside the water cooling system and need to stop the laser if the water temperature goes over around 30 C. The reason for this is that life of the tube and power output are both seriously affected by heat.

My problem is that I am supposed to issue an M999 command to recover from a MAXTEMP event (according to the serial output) but M999 seems to have no effect and I want it to auto recover without intervention once MAXTEMP-10 has happened anyway.

There is also the problem that the instant MAXTEMP occurs the laser switches off but the XY axis keeps working until the buffer is clear. No point at all in re-starting if it has lost some XY movements while it wasn't cutting.

I find it really really difficult to find my way round Marlin, little logic to where functions are found or called from. A starting point would be a list of which functions/variables/assignments are in which files. I had thought I should be able to get this info from Arduino somewhere but have failed to find it.

[Marm]

Did you also try to arduino forums? Usually somebody there will know something.

[Mjolinor]

I haven't yet mainly because all of the world's knowledge is here on this forum.

[old man emu]

Roxy is doing exams. Or maybe AArdvark.

OME

[3dkarma]

There's a great tool called doxygen which you can use to generate documentation from source code, including lists of functions in files, call references, file inclusion references and the like. You can see the documentation generated for Marlin at www.3dkarma.com/Marlin/html. Click on the Files link in the navigation tab, then keep expanding the tree until you get to the list of files.

The quality of doxygen's output is dependent on how will the code is documented in-line. Unfortunately Marlin doesn't have much in the way of in-line documentation, so you won't see much descriptive information in doxygen, but you will at least be able to get information on what's where and what gets called where and by what.