Adding M117 Support to Gen6 Firmware

This article details how I added support for the M117 GCode that I used for the Auto Bed Leveling approach. The standard Gen6 firmware doesn't support this GCode.


This is more for my own recollection in case I need to add it to future builds.


process_g_code.pde: Line 680 (in the switch statement after case 116)


Handle the M117 GCode and return the data in the appropriate format.



case 117:
Serial.print("C: X");
        Serial.print(zeroHit.x);
        Serial.print(" Y");
        Serial.print(zeroHit.y);
        Serial.print(" Z");
        Serial.print(zeroHit.z);
        Serial.print(" E");
        Serial.println(zeroHit.e);
break;

cartesian_dda.pde: Line 391 (in the if (read_switch(min_pin, inv) ) statement)

When an end-stop is hit, store the current step count.

   if (min_pin == X_MIN_PIN)

       zeroHit.x = current;

   if (min_pin == Y_MIN_PIN)

       zeroHit.y = current;

   if (min_pin == Z_MIN_PIN)

       zeroHit.z = current;

configuration.h: Line 329 (just before #endif)

Increase the variables scope.

extern LongPoint zeroHit;

FiveD-GCode_Interpreter.pde: Line 121 (after FloatPoint where_i_am;)

Variable declaration.

LongPoint zeroHit;

That's all there is to it, a quick recompile and upload later and the Gen6 hardware should now support M117.