extruder runout prevention.

Marlin/Configuration.h

@@ -156,6 +156,14 @@
   #endif
 #endif // PIDTEMP
 
+//  extruder run-out prevention. 
+//if the machine is idle, and the temperature over MINTEMP, every couple of SECONDS some filament is extruded
+//#define EXTRUDER_RUNOUT_PREVENT  
+#define EXTRUDER_RUNOUT_MINTEMP 190  
+#define EXTRUDER_RUNOUT_SECONDS 60
+#define EXTRUDER_RUNOUT_EXTRUDE 10 //mm filament
+#define EXTRUDER_RUNOUT_SPEED 20  //extrusion speed
+
 
 //===========================================================================
 //=============================Mechanical Settings===========================