What is M302 undo command?

[Lateralg]

M302 allows cold extrusion.
After sending M302, how do I return to normal?

[Dale Reed]

Lateralg,

Couldn't find one on RepRap wiki or Marlin sites. I did find a firmware called "5DPrint" that uses M302 P1 to allow cold extrudes, and M302 P0 to disallow cold extrudes. I suppose you could try those commands and see what happens.... Maybe Marlin will incorporate (someday)?

Otherwise, I suppose you'll have to initiate a machine reboot or cycle power...

Dale

[Tim]

The actual Marlin code for M302 is:

Code: Select all

    case 302: // allow cold extrudes, or set the minimum extrude temperature
    {
          float temp = .0;
          if (code_seen('S')) temp=code_value();
      set_extrude_min_temp(temp);
    }
    break;

So if you do just "M302", this is equivalent to "M302 S0", or allow extruding at any temperature above 0C.
If you want to return to normal, do for example "M302 S150", with S set to something slightly below your set temperature.

[Dale Reed]

The source code!!! OF COURSE!!! I'll have to save a copy on my work PC so I can offer USEFUL responses when I sneak a look at the forum when I'm supposed to be working....

Thanks, Tim!
Dale

[sprior]

Use The Source Luke!