Merge pull request #2989 from AnHardt/fix2661

Pre home display - Stepper release

Marlin/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/Configuration_adv.h

  * The maximum buffered steps/sec of the extruder motor is called "se".
  * Start autotemp mode with M109 S<mintemp> B<maxtemp> F<factor>
  * The target temperature is set to mintemp+factor*se[steps/sec] and is limited by
- * mintemp and maxtemp. Turn this off by excuting M109 without F*
+ * mintemp and maxtemp. Turn this off by executing M109 without F*
  * Also, if the temperature is set to a value below mintemp, it will not be changed by autotemp.
  * On an Ultimaker, some initial testing worked with M109 S215 B260 F1 in the start.gcode
  */
 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
-#define DEFAULT_STEPPER_DEACTIVE_TIME 60
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
+#define DEFAULT_STEPPER_DEACTIVE_TIME 120
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/Marlin.h

 extern float min_pos[3]; // axis[n].min_pos
 extern float max_pos[3]; // axis[n].max_pos
 extern bool axis_known_position[3]; // axis[n].is_known
+extern bool axis_homed[3]; // axis[n].is_homed
 
 #if ENABLED(DELTA)
   extern float delta[3];

Marlin/Marlin_main.cpp

 float current_position[NUM_AXIS] = { 0.0 };
 static float destination[NUM_AXIS] = { 0.0 };
 bool axis_known_position[3] = { false };
+bool axis_homed[3] = { false };
 
 static long gcode_N, gcode_LastN, Stopped_gcode_LastN = 0;
 
 
   static void run_z_probe() {
 
+    refresh_cmd_timeout(); // to prevent stepper_inactive_time from running out and EXTRUDER_RUNOUT_PREVENT from extruding
+
     #if ENABLED(DELTA)
 
       float start_z = current_position[Z_AXIS];
     feedrate = 0.0;
     endstops_hit_on_purpose(); // clear endstop hit flags
     axis_known_position[axis] = true;
+    axis_homed[axis] = true;
 
     #if ENABLED(Z_PROBE_SLED)
       // bring Z probe back
     }
 
     idle();
+    refresh_cmd_timeout(); // to prevent stepper_inactive_time from running out
 
     #ifdef TEMP_RESIDENCY_TIME
       // start/restart the TEMP_RESIDENCY_TIME timer whenever we reach target temp for the first time
   }
 
   LCD_MESSAGEPGM(MSG_HEATING_COMPLETE);
-  refresh_cmd_timeout();
   print_job_start_ms = previous_cmd_ms;
 }
 
         #endif
       }
       idle();
+      refresh_cmd_timeout(); // to prevent stepper_inactive_time from running out
     }
     LCD_MESSAGEPGM(MSG_BED_DONE);
-    refresh_cmd_timeout();
   }
 
 #endif // HAS_TEMP_BED
 
   if (stepper_inactive_time && ms > previous_cmd_ms + stepper_inactive_time
       && !ignore_stepper_queue && !blocks_queued()) {
-    #if DISABLE_X == true
+    #if DISABLE_INACTIVE_X == true
       disable_x();
     #endif
-    #if DISABLE_Y == true
+    #if DISABLE_INACTIVE_Y == true
       disable_y();
     #endif
-    #if DISABLE_Z == true
+    #if DISABLE_INACTIVE_Z == true
       disable_z();
     #endif
-    #if DISABLE_E == true
+    #if DISABLE_INACTIVE_E == true
       disable_e0();
       disable_e1();
       disable_e2();

Marlin/dogm_lcd_implementation.h

   lcd_print(itostr3(int(heater >= 0 ? degHotend(heater) : degBed()) + 0.5));
 
   lcd_printPGM(PSTR(LCD_STR_DEGREE " "));
-  if (!isHeatingHotend(0)) {
+  if (heater >= 0 ? !isHeatingHotend(heater) : !isHeatingBed()) {
     u8g.drawBox(x+7,y,2,2);
   }
   else {
     }
 
   // X, Y, Z-Coordinates
+  // Before homing the axis letters are blinking 'X' <-> '?'.
+  // When axis is homed but axis_known_position is false the axis letters are blinking 'X' <-> ' '.
+  // When everything is ok you see a constant 'X'.
   #define XYZ_BASELINE 38
   lcd_setFont(FONT_STATUSMENU);
 
   #endif
   u8g.setColorIndex(0); // white on black
   u8g.setPrintPos(2, XYZ_BASELINE);
-  lcd_print('X');
+  if (blink & 1)
+    lcd_printPGM(PSTR("X"));
+  else {
+    if (!axis_homed[X_AXIS])
+      lcd_printPGM(PSTR("?"));
+    else
+      #if DISABLED(DISABLE_REDUCED_ACCURACY_WARNING)
+        if (!axis_known_position[X_AXIS])
+          lcd_printPGM(PSTR(" "));
+        else
+      #endif
+      lcd_printPGM(PSTR("X"));
+  }
   u8g.drawPixel(8, XYZ_BASELINE - 5);
   u8g.drawPixel(8, XYZ_BASELINE - 3);
   u8g.setPrintPos(10, XYZ_BASELINE);
-  if (axis_known_position[X_AXIS])
-    lcd_print(ftostr31ns(current_position[X_AXIS]));
-  else
-    lcd_printPGM(PSTR("---"));
+  lcd_print(ftostr31ns(current_position[X_AXIS]));
+
   u8g.setPrintPos(43, XYZ_BASELINE);
-  lcd_print('Y');
+  if (blink & 1)
+    lcd_printPGM(PSTR("Y"));
+  else {
+    if (!axis_homed[Y_AXIS])
+      lcd_printPGM(PSTR("?"));
+    else
+      #if DISABLED(DISABLE_REDUCED_ACCURACY_WARNING)
+        if (!axis_known_position[Y_AXIS])
+          lcd_printPGM(PSTR(" "));
+        else
+      #endif
+      lcd_printPGM(PSTR("Y"));
+  }
   u8g.drawPixel(49, XYZ_BASELINE - 5);
   u8g.drawPixel(49, XYZ_BASELINE - 3);
   u8g.setPrintPos(51, XYZ_BASELINE);
-  if (axis_known_position[Y_AXIS])
-    lcd_print(ftostr31ns(current_position[Y_AXIS]));
-  else
-    lcd_printPGM(PSTR("---"));
+  lcd_print(ftostr31ns(current_position[Y_AXIS]));
+
   u8g.setPrintPos(83, XYZ_BASELINE);
-  lcd_print('Z');
+  if (blink & 1)
+    lcd_printPGM(PSTR("Z"));
+  else {
+    if (!axis_homed[Z_AXIS])
+      lcd_printPGM(PSTR("?"));
+    else
+      #if DISABLED(DISABLE_REDUCED_ACCURACY_WARNING)
+        if (!axis_known_position[Z_AXIS])
+          lcd_printPGM(PSTR(" "));
+        else
+      #endif
+      lcd_printPGM(PSTR("Z"));
+  }
   u8g.drawPixel(89, XYZ_BASELINE - 5);
   u8g.drawPixel(89, XYZ_BASELINE - 3);
   u8g.setPrintPos(91, XYZ_BASELINE);
-  if (axis_known_position[Z_AXIS])
-    lcd_print(ftostr32sp(current_position[Z_AXIS]));
-  else
-    lcd_printPGM(PSTR("---.--"));
+  lcd_print(ftostr32sp(current_position[Z_AXIS]));
   u8g.setColorIndex(1); // black on white
 
   // Feedrate

Marlin/example_configurations/Felix/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/Felix/Configuration_DUAL.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 #define DISABLE_E false // For all extruders
 #define DISABLE_INACTIVE_EXTRUDER true //disable only inactive extruders and keep active extruder enabled
 

Marlin/example_configurations/Felix/Configuration_adv.h

 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
 #define DEFAULT_STEPPER_DEACTIVE_TIME 60
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/example_configurations/Hephestos/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/Hephestos/Configuration_adv.h

 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
 #define DEFAULT_STEPPER_DEACTIVE_TIME 60
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/example_configurations/K8200/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false // not for K8200 -> looses Steps
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/K8200/Configuration_adv.h

 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
 #define DEFAULT_STEPPER_DEACTIVE_TIME 60
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/example_configurations/RepRapWorld/Megatronics/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/RigidBot/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/RigidBot/Configuration_adv.h

 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
 #define DEFAULT_STEPPER_DEACTIVE_TIME 60
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/example_configurations/SCARA/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/SCARA/Configuration_adv.h

 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
 #define DEFAULT_STEPPER_DEACTIVE_TIME 240
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/example_configurations/TAZ4/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/TAZ4/Configuration_adv.h

 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
 #define DEFAULT_STEPPER_DEACTIVE_TIME 60
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/example_configurations/WITBOX/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z true
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/WITBOX/Configuration_adv.h

 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
 #define DEFAULT_STEPPER_DEACTIVE_TIME 60
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/example_configurations/adafruit/ST7565/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/delta/biv2.5/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/delta/biv2.5/Configuration_adv.h

 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
 #define DEFAULT_STEPPER_DEACTIVE_TIME 0
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/example_configurations/delta/generic/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/delta/generic/Configuration_adv.h

 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
 #define DEFAULT_STEPPER_DEACTIVE_TIME 60
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/example_configurations/delta/kossel_mini/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/delta/kossel_mini/Configuration_adv.h

 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
 #define DEFAULT_STEPPER_DEACTIVE_TIME 60
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/example_configurations/delta/kossel_pro/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/delta/kossel_pro/Configuration_adv.h

 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
 #define DEFAULT_STEPPER_DEACTIVE_TIME 60
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/example_configurations/makibox/Configuration.h

 #define Z_ENABLE_ON 0
 #define E_ENABLE_ON 0 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/makibox/Configuration_adv.h

 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
 #define DEFAULT_STEPPER_DEACTIVE_TIME 60
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/example_configurations/tvrrug/Round2/Configuration.h

 #define Z_ENABLE_ON 1
 #define E_ENABLE_ON 1 // For all extruders
 
-// Disables axis when it's not being used.
+// Disables axis stepper immediately when it's not being used.
 // WARNING: When motors turn off there is a chance of losing position accuracy!
 #define DISABLE_X false
 #define DISABLE_Y false
 #define DISABLE_Z false
+// Warn on display about possibly reduced accuracy
+//#define DISABLE_REDUCED_ACCURACY_WARNING
 
 // @section extruder
 

Marlin/example_configurations/tvrrug/Round2/Configuration_adv.h

 #define INVERT_E_STEP_PIN false
 
 // Default stepper release if idle. Set to 0 to deactivate.
+// Steppers will shut down DEFAULT_STEPPER_DEACTIVE_TIME seconds after the last move when DISABLE_INACTIVE_? is true.
+// Time can be set by M18 and M84.
 #define DEFAULT_STEPPER_DEACTIVE_TIME 60
+#define DISABLE_INACTIVE_X true
+#define DISABLE_INACTIVE_Y true
+#define DISABLE_INACTIVE_Z true  // set to false if the nozzle will fall down on your printed part when print has finished.
+#define DISABLE_INACTIVE_E true
 
 #define DEFAULT_MINIMUMFEEDRATE       0.0     // minimum feedrate
 #define DEFAULT_MINTRAVELFEEDRATE     0.0

Marlin/ultralcd.cpp

     }
     #if ENABLED(DOGLCD)  // Changes due to different driver architecture of the DOGM display
         if (lcdDrawUpdate) {
-          blink++;     // Variable for fan animation and alive dot
+          blink++;     // Variable for animation and alive dot
           u8g.firstPage();
           do {
             lcd_setFont(FONT_MENU);
             u8g.setPrintPos(125, 0);
-            if (blink % 2) u8g.setColorIndex(1); else u8g.setColorIndex(0); // Set color for the alive dot
+            if (blink & 1) u8g.setColorIndex(1); else u8g.setColorIndex(0); // Set color for the alive dot
             u8g.drawPixel(127, 63); // draw alive dot
             u8g.setColorIndex(1); // black on white
             (*currentMenu)();
           } while (u8g.nextPage());
         }
     #else
-      if (lcdDrawUpdate)
+      if (lcdDrawUpdate) {
+        blink++;     // Variable for animation
         (*currentMenu)();
-    #endif
+      }
+      #endif
 
     #if ENABLED(LCD_HAS_STATUS_INDICATORS)
       lcd_implementation_update_indicators();

Marlin/ultralcd_implementation_hitachi_HD44780.h

 
 /**
 * Implementation of the LCD display routines for a Hitachi HD44780 display. These are common LCD character displays.
-* When selecting the Russian language, a slightly different LCD implementation is used to handle UTF8 characters.
 **/
 
-//#if DISABLED(REPRAPWORLD_KEYPAD)
-//  extern volatile uint8_t buttons;  //the last checked buttons in a bit array.
-//#else
-  extern volatile uint8_t buttons;  //an extended version of the last checked buttons in a bit array.
-//#endif
+static unsigned char blink = 0; // Variable for animation
+extern volatile uint8_t buttons;  //an extended version of the last checked buttons in a bit array.
 
 ////////////////////////////////////
 // Setup button and encode mappings for each panel (into 'buttons' variable
         LCD_TEMP(degBed(), degTargetBed(), LCD_STR_BEDTEMP[0]);
 
       #else
+        // Before homing the axis letters are blinking 'X' <-> '?'.
+        // When axis is homed but axis_known_position is false the axis letters are blinking 'X' <-> ' '.
+        // When everything is ok you see a constant 'X'.
+
+        if (blink & 1)
+          lcd_printPGM(PSTR("X"));
+        else {
+          if (!axis_homed[X_AXIS])
+            lcd_printPGM(PSTR("?"));
+          else 
+            #if DISABLED(DISABLE_REDUCED_ACCURACY_WARNING)
+              if (!axis_known_position[X_AXIS])
+                lcd_printPGM(PSTR(" "));
+              else
+            #endif
+            lcd_printPGM(PSTR("X"));
+        }
 
-        lcd.print('X');
-        if (axis_known_position[X_AXIS])
-          lcd.print(ftostr4sign(current_position[X_AXIS]));
-        else
-          lcd_printPGM(PSTR(" ---"));
-
-        lcd_printPGM(PSTR(" Y"));
-        if (axis_known_position[Y_AXIS])
-          lcd.print(ftostr4sign(current_position[Y_AXIS]));
-        else
-          lcd_printPGM(PSTR(" ---"));
+        lcd.print(ftostr4sign(current_position[X_AXIS]));
+
+        lcd_printPGM(PSTR(" "));
+        if (blink & 1)
+          lcd_printPGM(PSTR("Y"));
+        else {
+          if (!axis_homed[Y_AXIS])
+            lcd_printPGM(PSTR("?"));
+          else 
+            #if DISABLED(DISABLE_REDUCED_ACCURACY_WARNING)
+              if (!axis_known_position[Y_AXIS])
+                lcd_printPGM(PSTR(" "));
+              else
+            #endif
+            lcd_printPGM(PSTR("Y"));
+        }
+        lcd.print(ftostr4sign(current_position[Y_AXIS]));
 
       #endif // EXTRUDERS > 1 || TEMP_SENSOR_BED != 0
 
     #endif // LCD_WIDTH >= 20
 
     lcd.setCursor(LCD_WIDTH - 8, 1);
-    lcd_printPGM(PSTR("Z "));
-    if (axis_known_position[Z_AXIS])
-      lcd.print(ftostr32sp(current_position[Z_AXIS] + 0.00001));
-    else
-      lcd_printPGM(PSTR("---.--"));
+    if (blink & 1)
+      lcd_printPGM(PSTR("Z"));
+    else {
+      if (!axis_homed[Z_AXIS])
+        lcd_printPGM(PSTR("?"));
+      else 
+        #if DISABLED(DISABLE_REDUCED_ACCURACY_WARNING)
+          if (!axis_known_position[Z_AXIS])
+            lcd_printPGM(PSTR(" "));
+          else
+        #endif
+        lcd_printPGM(PSTR("Z"));
+    }
+    lcd.print(ftostr32sp(current_position[Z_AXIS] + 0.00001));
 
   #endif // LCD_HEIGHT > 2