Merge pull request #6264 from thinkyhead/rc_five_extruders

Support up to 5 extruders in Marlin

Marlin/Conditionals_post.h

     #define HEATER_3_USES_THERMISTOR
   #endif
 
+  #if TEMP_SENSOR_4 <= -2
+    #error "MAX6675 / MAX31855 Thermocouples not supported for TEMP_SENSOR_4"
+  #elif TEMP_SENSOR_4 == -1
+    #define HEATER_4_USES_AD595
+  #elif TEMP_SENSOR_4 == 0
+    #undef HEATER_4_MINTEMP
+    #undef HEATER_4_MAXTEMP
+  #elif TEMP_SENSOR_4 > 0
+    #define THERMISTORHEATER_4 TEMP_SENSOR_4
+    #define HEATER_4_USES_THERMISTOR
+  #endif
+
   #if TEMP_SENSOR_BED <= -2
     #error "MAX6675 / MAX31855 Thermocouples not supported for TEMP_SENSOR_BED"
   #elif TEMP_SENSOR_BED == -1
   #define HAS_TEMP_1 (PIN_EXISTS(TEMP_1) && TEMP_SENSOR_1 != 0 && TEMP_SENSOR_1 > -2)
   #define HAS_TEMP_2 (PIN_EXISTS(TEMP_2) && TEMP_SENSOR_2 != 0 && TEMP_SENSOR_2 > -2)
   #define HAS_TEMP_3 (PIN_EXISTS(TEMP_3) && TEMP_SENSOR_3 != 0 && TEMP_SENSOR_3 > -2)
+  #define HAS_TEMP_4 (PIN_EXISTS(TEMP_4) && TEMP_SENSOR_4 != 0 && TEMP_SENSOR_4 > -2)
   #define HAS_TEMP_BED (PIN_EXISTS(TEMP_BED) && TEMP_SENSOR_BED != 0 && TEMP_SENSOR_BED > -2)
   #define HAS_HEATER_0 (PIN_EXISTS(HEATER_0))
   #define HAS_HEATER_1 (PIN_EXISTS(HEATER_1))
   #define HAS_HEATER_2 (PIN_EXISTS(HEATER_2))
   #define HAS_HEATER_3 (PIN_EXISTS(HEATER_3))
+  #define HAS_HEATER_4 (PIN_EXISTS(HEATER_4))
   #define HAS_HEATER_BED (PIN_EXISTS(HEATER_BED))
   #define HAS_AUTO_FAN_0 (PIN_EXISTS(E0_AUTO_FAN))
   #define HAS_AUTO_FAN_1 (HOTENDS > 1 && PIN_EXISTS(E1_AUTO_FAN))
   #define HAS_AUTO_FAN_2 (HOTENDS > 2 && PIN_EXISTS(E2_AUTO_FAN))
   #define HAS_AUTO_FAN_3 (HOTENDS > 3 && PIN_EXISTS(E3_AUTO_FAN))
+  #define HAS_AUTO_FAN_4 (HOTENDS > 4 && PIN_EXISTS(E4_AUTO_FAN))
   #define HAS_AUTO_FAN (HAS_AUTO_FAN_0 || HAS_AUTO_FAN_1 || HAS_AUTO_FAN_2 || HAS_AUTO_FAN_3)
   #define AUTO_1_IS_0 (E1_AUTO_FAN_PIN == E0_AUTO_FAN_PIN)
   #define AUTO_2_IS_0 (E2_AUTO_FAN_PIN == E0_AUTO_FAN_PIN)
   #define AUTO_3_IS_0 (E3_AUTO_FAN_PIN == E0_AUTO_FAN_PIN)
   #define AUTO_3_IS_1 (E3_AUTO_FAN_PIN == E1_AUTO_FAN_PIN)
   #define AUTO_3_IS_2 (E3_AUTO_FAN_PIN == E2_AUTO_FAN_PIN)
+  #define AUTO_4_IS_0 (E4_AUTO_FAN_PIN == E0_AUTO_FAN_PIN)
+  #define AUTO_4_IS_1 (E4_AUTO_FAN_PIN == E1_AUTO_FAN_PIN)
+  #define AUTO_4_IS_2 (E4_AUTO_FAN_PIN == E2_AUTO_FAN_PIN)
+  #define AUTO_4_IS_3 (E4_AUTO_FAN_PIN == E3_AUTO_FAN_PIN)
   #define HAS_FAN0 (PIN_EXISTS(FAN))
   #define HAS_FAN1 (PIN_EXISTS(FAN1) && CONTROLLERFAN_PIN != FAN1_PIN && E0_AUTO_FAN_PIN != FAN1_PIN && E1_AUTO_FAN_PIN != FAN1_PIN && E2_AUTO_FAN_PIN != FAN1_PIN && E3_AUTO_FAN_PIN != FAN1_PIN)
   #define HAS_FAN2 (PIN_EXISTS(FAN2) && CONTROLLERFAN_PIN != FAN2_PIN && E0_AUTO_FAN_PIN != FAN2_PIN && E1_AUTO_FAN_PIN != FAN2_PIN && E2_AUTO_FAN_PIN != FAN2_PIN && E3_AUTO_FAN_PIN != FAN2_PIN)
       #define WRITE_HEATER_2(v) WRITE(HEATER_2_PIN, v)
       #if HOTENDS > 3
         #define WRITE_HEATER_3(v) WRITE(HEATER_3_PIN, v)
-      #endif
-    #endif
-  #endif
+        #if HOTENDS > 4
+          #define WRITE_HEATER_4(v) WRITE(HEATER_4_PIN, v)
+        #endif // HOTENDS > 4
+      #endif // HOTENDS > 3
+    #endif // HOTENDS > 2
+  #endif // HOTENDS > 1
   #if ENABLED(HEATERS_PARALLEL)
     #define WRITE_HEATER_0(v) { WRITE_HEATER_0P(v); WRITE_HEATER_1(v); }
   #else

Marlin/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 0
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/Marlin.h

   #define disable_e2() NOOP
   #define  enable_e3() NOOP
   #define disable_e3() NOOP
+  #define  enable_e4() NOOP
+  #define disable_e4() NOOP
 
 #else // !MIXING_EXTRUDER
 
     #define disable_e3() NOOP
   #endif
 
+  #if E_STEPPERS > 4 && HAS_E4_ENABLE
+    #define  enable_e4() E4_ENABLE_WRITE( E_ENABLE_ON)
+    #define disable_e4() E4_ENABLE_WRITE(!E_ENABLE_ON)
+  #else
+    #define  enable_e4() NOOP
+    #define disable_e4() NOOP
+  #endif
+
 #endif // !MIXING_EXTRUDER
 
 #if ENABLED(G38_PROBE_TARGET)

Marlin/Marlin_main.cpp

               || E2_ENABLE_READ == E_ENABLE_ON
               #if E_STEPPERS > 3
                 || E3_ENABLE_READ == E_ENABLE_ON
-              #endif
-            #endif
-          #endif
+                #if E_STEPPERS > 4
+                  || E4_ENABLE_READ == E_ENABLE_ON
+                #endif // E_STEPPERS > 4
+              #endif // E_STEPPERS > 3
+            #endif // E_STEPPERS > 2
+          #endif // E_STEPPERS > 1
       ) {
         lastMotorOn = ms; //... set time to NOW so the fan will turn on
       }
   enable_e1();
   enable_e2();
   enable_e3();
+  enable_e4();
 }
 
 void disable_e_steppers() {
   disable_e1();
   disable_e2();
   disable_e3();
+  disable_e4();
 }
 
 void disable_all_steppers() {
                   oldstatus = E3_ENABLE_READ;
                   enable_e3();
                   break;
-              #endif
-            #endif
-          #endif
+                #if E_STEPPERS > 4
+                  case 4:
+                    oldstatus = E4_ENABLE_READ;
+                    enable_e4();
+                    break;
+                #endif // E_STEPPERS > 4
+              #endif // E_STEPPERS > 3
+            #endif // E_STEPPERS > 2
+          #endif // E_STEPPERS > 1
         }
       #endif // !SWITCHING_EXTRUDER
 
                 case 3:
                   E3_ENABLE_WRITE(oldstatus);
                   break;
-              #endif
-            #endif
-          #endif
+                #if E_STEPPERS > 4
+                  case 4:
+                    E4_ENABLE_WRITE(oldstatus);
+                    break;
+                #endif // E_STEPPERS > 4
+              #endif // E_STEPPERS > 3
+            #endif // E_STEPPERS > 2
+          #endif // E_STEPPERS > 1
         }
       #endif // !SWITCHING_EXTRUDER
     }

Marlin/SanityCheck.h

  */
 #if EXTRUDERS > 1
 
-  #if EXTRUDERS > 4
-    #error "The maximum number of EXTRUDERS in Marlin is 4."
+  #if EXTRUDERS > 5
+    #error "Marlin supports a maximum of 5 EXTRUDERS."
   #endif
 
   #if ENABLED(TEMP_SENSOR_1_AS_REDUNDANT)
     #endif
     #if HOTENDS > 3
       #if TEMP_SENSOR_3 == 0
-        #error "TEMP_SENSOR_3 is required with 4 HOTENDS."
+        #error "TEMP_SENSOR_3 is required with 4 or more HOTENDS."
       #elif !HAS_HEATER_3
         #error "HEATER_3_PIN not defined for this board."
       #elif !PIN_EXISTS(TEMP_3)
         #error "TEMP_3_PIN not defined for this board."
       #endif
+      #if HOTENDS > 4
+        #if TEMP_SENSOR_4 == 0
+          #error "TEMP_SENSOR_4 is required with 5 HOTENDS."
+        #elif !HAS_HEATER_4
+          #error "HEATER_4_PIN not defined for this board."
+        #elif !PIN_EXISTS(TEMP_4)
+          #error "TEMP_4_PIN not defined for this board."
+        #endif
+      #elif TEMP_SENSOR_4 != 0
+        #error "TEMP_SENSOR_4 shouldn't be set with only 4 extruders."
+      #endif
     #elif TEMP_SENSOR_3 != 0
       #error "TEMP_SENSOR_3 shouldn't be set with only 3 extruders."
+    #elif TEMP_SENSOR_4 != 0
+      #error "TEMP_SENSOR_4 shouldn't be set with only 3 extruders."
     #endif
   #elif TEMP_SENSOR_2 != 0
     #error "TEMP_SENSOR_2 shouldn't be set with only 2 extruders."
   #elif TEMP_SENSOR_3 != 0
     #error "TEMP_SENSOR_3 shouldn't be set with only 2 extruders."
+  #elif TEMP_SENSOR_4 != 0
+    #error "TEMP_SENSOR_4 shouldn't be set with only 2 extruders."
   #endif
 #elif TEMP_SENSOR_1 != 0 && DISABLED(TEMP_SENSOR_1_AS_REDUNDANT)
   #error "TEMP_SENSOR_1 shouldn't be set with only 1 extruder."
   #error "TEMP_SENSOR_2 shouldn't be set with only 1 extruder."
 #elif TEMP_SENSOR_3 != 0
   #error "TEMP_SENSOR_3 shouldn't be set with only 1 extruder."
+#elif TEMP_SENSOR_4 != 0
+  #error "TEMP_SENSOR_4 shouldn't be set with only 1 extruder."
 #endif
 
 #if ENABLED(TEMP_SENSOR_1_AS_REDUNDANT) && TEMP_SENSOR_1 == 0
 /**
  * Test Extruder Pins
  */
-#if EXTRUDERS > 3
+#if EXTRUDERS > 4
+  #if !PIN_EXISTS(E4_STEP) || !PIN_EXISTS(E4_DIR) || !PIN_EXISTS(E4_ENABLE)
+    #error "E4_STEP_PIN, E4_DIR_PIN, or E4_ENABLE_PIN not defined for this board."
+  #endif
+#elif EXTRUDERS > 3
   #if !PIN_EXISTS(E3_STEP) || !PIN_EXISTS(E3_DIR) || !PIN_EXISTS(E3_ENABLE)
     #error "E3_STEP_PIN, E3_DIR_PIN, or E3_ENABLE_PIN not defined for this board."
   #endif

Marlin/configuration_store.cpp

  *
  */
 
-#define EEPROM_VERSION "V31"
+#define EEPROM_VERSION "V32"
 
 // Change EEPROM version if these are changed:
 #define EEPROM_OFFSET 100
 /**
  * V31 EEPROM Layout:
  *
- *  100  Version                                   (char x4)
- *  104  EEPROM Checksum                           (uint16_t)
+ *  100  Version                                    (char x4)
+ *  104  EEPROM Checksum                            (uint16_t)
  *
  *  106            E_STEPPERS (uint8_t)
- *  107  M92 XYZE  planner.axis_steps_per_mm (float x4 ... x7)
- *  123  M203 XYZE planner.max_feedrate_mm_s (float x4 ... x7)
- *  139  M201 XYZE planner.max_acceleration_mm_per_s2 (uint32_t x4 ... x7)
- *  155  M204 P    planner.acceleration (float)
- *  159  M204 R    planner.retract_acceleration (float)
- *  163  M204 T    planner.travel_acceleration (float)
- *  167  M205 S    planner.min_feedrate_mm_s (float)
+ *  107  M92 XYZE  planner.axis_steps_per_mm        (float x4 ... x8)
+ *  123  M203 XYZE planner.max_feedrate_mm_s        (float x4 ... x8)
+ *  139  M201 XYZE planner.max_acceleration_mm_per_s2 (uint32_t x4 ... x8)
+ *  155  M204 P    planner.acceleration             (float)
+ *  159  M204 R    planner.retract_acceleration     (float)
+ *  163  M204 T    planner.travel_acceleration      (float)
+ *  167  M205 S    planner.min_feedrate_mm_s        (float)
  *  171  M205 T    planner.min_travel_feedrate_mm_s (float)
- *  175  M205 B    planner.min_segment_time (ulong)
- *  179  M205 X    planner.max_jerk[X_AXIS] (float)
- *  183  M205 Y    planner.max_jerk[Y_AXIS] (float)
- *  187  M205 Z    planner.max_jerk[Z_AXIS] (float)
- *  191  M205 E    planner.max_jerk[E_AXIS] (float)
- *  195  M206 XYZ  home_offset (float x3)
- *  207  M218 XYZ  hotend_offset (float x3 per additional hotend)
+ *  175  M205 B    planner.min_segment_time         (ulong)
+ *  179  M205 X    planner.max_jerk[X_AXIS]         (float)
+ *  183  M205 Y    planner.max_jerk[Y_AXIS]         (float)
+ *  187  M205 Z    planner.max_jerk[Z_AXIS]         (float)
+ *  191  M205 E    planner.max_jerk[E_AXIS]         (float)
+ *  195  M206 XYZ  home_offset                      (float x3)
+ *  207  M218 XYZ  hotend_offset                    (float x3 per additional hotend)
  *
- * Mesh bed leveling:
- *  219  M420 S    from mbl.status (bool)
- *  220            mbl.z_offset (float)
- *  224            GRID_MAX_POINTS_X (uint8 as set in firmware)
- *  225            GRID_MAX_POINTS_Y (uint8 as set in firmware)
- *  226 G29 S3 XYZ z_values[][] (float x9, by default, up to float x 81) +288
+ * Mesh bed leveling:                               43 bytes
+ *  219  M420 S    from mbl.status                  (bool)
+ *  220            mbl.z_offset                     (float)
+ *  224            GRID_MAX_POINTS_X                (uint8_t)
+ *  225            GRID_MAX_POINTS_Y                (uint8_t)
+ *  226 G29 S3 XYZ z_values[][]                     (float x9, up to float x 81) +288
  *
- * AUTO BED LEVELING
- *  262  M851      zprobe_zoffset (float)
+ * AUTO BED LEVELING                                4 bytes
+ *  262  M851      zprobe_zoffset                   (float)
  *
- * ABL_PLANAR (or placeholder):                    36 bytes
- *  266            planner.bed_level_matrix        (matrix_3x3 = float x9)
+ * ABL_PLANAR (or placeholder):                     36 bytes
+ *  266            planner.bed_level_matrix         (matrix_3x3 = float x9)
  *
- * AUTO_BED_LEVELING_BILINEAR (or placeholder):    47 bytes
- *  302            GRID_MAX_POINTS_X               (uint8_t)
- *  303            GRID_MAX_POINTS_Y               (uint8_t)
- *  304            bilinear_grid_spacing           (int x2)   from G29: (B-F)/X, (R-L)/Y
- *  308  G29 L F   bilinear_start                  (int x2)
- *  312            bed_level_grid[][]              (float x9, up to float x256) +988
+ * AUTO_BED_LEVELING_BILINEAR (or placeholder):     47 bytes
+ *  302            GRID_MAX_POINTS_X                (uint8_t)
+ *  303            GRID_MAX_POINTS_Y                (uint8_t)
+ *  304            bilinear_grid_spacing            (int x2)
+ *  308  G29 L F   bilinear_start                   (int x2)
+ *  312            bed_level_grid[][]               (float x9, up to float x256) +988
  *
  * DELTA (if deltabot):                             48 bytes
  *  348  M666 XYZ  endstop_adj                      (float x3)
  *  388  M665 J    delta_tower_angle_trim[B]        (float)
  *  392  M665 K    delta_tower_angle_trim[C]        (float)
  *
- * Z_DUAL_ENDSTOPS (if not deltabot):              48 bytes
- *  348  M666 Z    z_endstop_adj                   (float)
- *  ---            dummy data                      (float x11)
+ * Z_DUAL_ENDSTOPS (if not deltabot):               48 bytes
+ *  348  M666 Z    z_endstop_adj                    (float)
+ *  ---            dummy data                       (float x11)
  *
- * ULTIPANEL:                                      6 bytes
- *  396  M145 S0 H lcd_preheat_hotend_temp         (int x2)
- *  400  M145 S0 B lcd_preheat_bed_temp            (int x2)
- *  404  M145 S0 F lcd_preheat_fan_speed           (int x2)
+ * ULTIPANEL:                                       6 bytes
+ *  396  M145 S0 H lcd_preheat_hotend_temp          (int x2)
+ *  400  M145 S0 B lcd_preheat_bed_temp             (int x2)
+ *  404  M145 S0 F lcd_preheat_fan_speed            (int x2)
  *
- * PIDTEMP:                                        66 bytes
- *  408  M301 E0 PIDC  Kp[0], Ki[0], Kd[0], Kc[0]  (float x4)
- *  424  M301 E1 PIDC  Kp[1], Ki[1], Kd[1], Kc[1]  (float x4)
- *  440  M301 E2 PIDC  Kp[2], Ki[2], Kd[2], Kc[2]  (float x4)
- *  456  M301 E3 PIDC  Kp[3], Ki[3], Kd[3], Kc[3]  (float x4)
- *  472  M301 L        lpq_len                     (int)
+ * PIDTEMP:                                         66 bytes
+ *  408  M301 E0 PIDC  Kp[0], Ki[0], Kd[0], Kc[0]   (float x4)
+ *  424  M301 E1 PIDC  Kp[1], Ki[1], Kd[1], Kc[1]   (float x4)
+ *  440  M301 E2 PIDC  Kp[2], Ki[2], Kd[2], Kc[2]   (float x4)
+ *  456  M301 E3 PIDC  Kp[3], Ki[3], Kd[3], Kc[3]   (float x4)
+ *  472  M301 E4 PIDC  Kp[3], Ki[3], Kd[3], Kc[3]   (float x4)
+ *  488  M301 L        lpq_len                      (int)
  *
  * PIDTEMPBED:                                      12 bytes
- *  474  M304 PID  thermalManager.bedKp, .bedKi, .bedKd (float x3)
+ *  490  M304 PID  thermalManager.bedKp, .bedKi, .bedKd (float x3)
  *
  * DOGLCD:                                          2 bytes
- *  486  M250 C    lcd_contrast                     (int)
+ *  502  M250 C    lcd_contrast                     (int)
  *
  * FWRETRACT:                                       29 bytes
- *  488  M209 S    autoretract_enabled              (bool)
- *  489  M207 S    retract_length                   (float)
- *  493  M207 W    retract_length_swap              (float)
- *  497  M207 F    retract_feedrate_mm_s            (float)
- *  501  M207 Z    retract_zlift                    (float)
- *  505  M208 S    retract_recover_length           (float)
- *  509  M208 W    retract_recover_length_swap      (float)
- *  513  M208 F    retract_recover_feedrate_mm_s    (float)
+ *  504  M209 S    autoretract_enabled              (bool)
+ *  505  M207 S    retract_length                   (float)
+ *  509  M207 W    retract_length_swap              (float)
+ *  513  M207 F    retract_feedrate_mm_s            (float)
+ *  517  M207 Z    retract_zlift                    (float)
+ *  521  M208 S    retract_recover_length           (float)
+ *  525  M208 W    retract_recover_length_swap      (float)
+ *  529  M208 F    retract_recover_feedrate_mm_s    (float)
  *
- * Volumetric Extrusion:                            17 bytes
- *  517  M200 D    volumetric_enabled               (bool)
- *  518  M200 T D  filament_size                    (float x4) (T0..3)
+ * Volumetric Extrusion:                            21 bytes
+ *  533  M200 D    volumetric_enabled               (bool)
+ *  534  M200 T D  filament_size                    (float x5) (T0..3)
  *
  * TMC2130 Stepper Current:                         20 bytes
- *  534  M906 X    stepperX current                 (uint16_t)
- *  536  M906 Y    stepperY current                 (uint16_t)
- *  538  M906 Z    stepperZ current                 (uint16_t)
- *  540  M906 X2   stepperX2 current                (uint16_t)
- *  542  M906 Y2   stepperY2 current                (uint16_t)
- *  544  M906 Z2   stepperZ2 current                (uint16_t)
- *  546  M906 E0   stepperE0 current                (uint16_t)
- *  548  M906 E1   stepperE1 current                (uint16_t)
- *  550  M906 E2   stepperE2 current                (uint16_t)
- *  552  M906 E3   stepperE3 current                (uint16_t)
+ *  554  M906 X    stepperX current                 (uint16_t)
+ *  556  M906 Y    stepperY current                 (uint16_t)
+ *  558  M906 Z    stepperZ current                 (uint16_t)
+ *  560  M906 X2   stepperX2 current                (uint16_t)
+ *  562  M906 Y2   stepperY2 current                (uint16_t)
+ *  564  M906 Z2   stepperZ2 current                (uint16_t)
+ *  566  M906 E0   stepperE0 current                (uint16_t)
+ *  568  M906 E1   stepperE1 current                (uint16_t)
+ *  570  M906 E2   stepperE2 current                (uint16_t)
+ *  572  M906 E3   stepperE3 current                (uint16_t)
  *
- *  554                                Minimum end-point
- * 1875 (554 + 36 + 9 + 288 + 988)     Maximum end-point
+ *  574                                Minimum end-point
+ * 1895 (574 + 36 + 9 + 288 + 988)     Maximum end-point
  *
  */
 #include "Marlin.h"
           CONFIG_ECHO_START;
           SERIAL_ECHOPAIR("  M200 T3 D", filament_size[3]);
           SERIAL_EOL;
-        #endif
-      #endif
-    #endif
+          #if EXTRUDERS > 4
+            CONFIG_ECHO_START;
+            SERIAL_ECHOPAIR("  M200 T4 D", filament_size[4]);
+            SERIAL_EOL;
+          #endif // EXTRUDERS > 4
+        #endif // EXTRUDERS > 3
+      #endif // EXTRUDERS > 2
+    #endif // EXTRUDERS > 1
 
     if (!volumetric_enabled) {
       CONFIG_ECHO_START;

Marlin/enum.h

   MeasureTemp_2,
   PrepareTemp_3,
   MeasureTemp_3,
+  PrepareTemp_4,
+  MeasureTemp_4,
   Prepare_FILWIDTH,
   Measure_FILWIDTH,
   StartupDelay // Startup, delay initial temp reading a tiny bit so the hardware can settle

Marlin/example_configurations/Cartesio/Configuration.h

 #define TEMP_SENSOR_1 -1
 #define TEMP_SENSOR_2 1
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 1
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/Cartesio/Configuration_adv.h

 //#define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 35
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/Felix/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 1
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/Felix/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/Felix/DUAL/Configuration.h

 #define TEMP_SENSOR_1 1
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 1
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR true
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/Hephestos/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 0
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/Hephestos/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/Hephestos_2/Configuration.h

  *
  * :{ '0': "Not used", '1':"100k / 4.7k - EPCOS", '2':"200k / 4.7k - ATC Semitec 204GT-2", '3':"Mendel-parts / 4.7k", '4':"10k !! do not use for a hotend. Bad resolution at high temp. !!", '5':"100K / 4.7k - ATC Semitec 104GT-2 (Used in ParCan & J-Head)", '6':"100k / 4.7k EPCOS - Not as accurate as Table 1", '7':"100k / 4.7k Honeywell 135-104LAG-J01", '8':"100k / 4.7k 0603 SMD Vishay NTCS0603E3104FXT", '9':"100k / 4.7k GE Sensing AL03006-58.2K-97-G1", '10':"100k / 4.7k RS 198-961", '11':"100k / 4.7k beta 3950 1%", '12':"100k / 4.7k 0603 SMD Vishay NTCS0603E3104FXT (calibrated for Makibox hot bed)", '13':"100k Hisens 3950  1% up to 300°C for hotend 'Simple ONE ' & hotend 'All In ONE'", '20':"PT100 (Ultimainboard V2.x)", '51':"100k / 1k - EPCOS", '52':"200k / 1k - ATC Semitec 204GT-2", '55':"100k / 1k - ATC Semitec 104GT-2 (Used in ParCan & J-Head)", '60':"100k Maker's Tool Works Kapton Bed Thermistor beta=3950", '66':"Dyze Design 4.7M High Temperature thermistor", '70':"the 100K thermistor found in the bq Hephestos 2", '71':"100k / 4.7k Honeywell 135-104LAF-J01", '147':"Pt100 / 4.7k", '1047':"Pt1000 / 4.7k", '110':"Pt100 / 1k (non-standard)", '1010':"Pt1000 / 1k (non standard)", '-3':"Thermocouple + MAX31855 (only for sensor 0)", '-2':"Thermocouple + MAX6675 (only for sensor 0)", '-1':"Thermocouple + AD595",'998':"Dummy 1", '999':"Dummy 2" }
  */
-#define TEMP_SENSOR_0   70
-#define TEMP_SENSOR_1   0
-#define TEMP_SENSOR_2   0
-#define TEMP_SENSOR_3   0
+#define TEMP_SENSOR_0 70
+#define TEMP_SENSOR_1 0
+#define TEMP_SENSOR_2 0
+#define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 0
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 // to check that the wiring to the thermistor is not broken.
 // Otherwise this would lead to the heater being powered on all the time.
 #define HEATER_0_MINTEMP 15
-//#define HEATER_1_MINTEMP 5
-//#define HEATER_2_MINTEMP 5
-//#define HEATER_3_MINTEMP 5
-//#define BED_MINTEMP 5
+#define HEATER_1_MINTEMP 5
+#define HEATER_2_MINTEMP 5
+#define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
+#define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 // This feature exists to protect your hotend from overheating accidentally, but *NOT* from thermistor short/failure!
 // You should use MINTEMP for thermistor short/failure protection.
 #define HEATER_0_MAXTEMP 250
-//#define HEATER_1_MAXTEMP 275
-//#define HEATER_2_MAXTEMP 275
-//#define HEATER_3_MAXTEMP 275
-//#define BED_MAXTEMP 150
+#define HEATER_1_MAXTEMP 275
+#define HEATER_2_MAXTEMP 275
+#define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
+#define BED_MAXTEMP 150
 
 //===========================================================================
 //============================= PID Settings ================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/Hephestos_2/Configuration_adv.h

 //#define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/K8200/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 5
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR true
 #define INVERT_E2_DIR true
 #define INVERT_E3_DIR true
+#define INVERT_E4_DIR true
 
 // @section homing
 // K8200: it is usual to have clamps for the glass plate on the heatbed

Marlin/example_configurations/K8200/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/K8400/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 0
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR true
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/K8400/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/K8400/Dual-head/Configuration.h

 #define TEMP_SENSOR_1 5
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 0
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR true
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/RepRapWorld/Megatronics/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 1
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/RigidBot/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 1
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR true
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/RigidBot/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/SCARA/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 1
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/SCARA/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/TAZ4/Configuration.h

 #define TEMP_SENSOR_1 7
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 7
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define INVERT_E1_DIR true
 #define INVERT_E2_DIR true
 #define INVERT_E3_DIR true
+#define INVERT_E4_DIR true
 
 // @section homing
 

Marlin/example_configurations/TAZ4/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/TinyBoy2/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #if ENABLED(TB2_HEATBED_MOD)
   // K8200 Heatbed 1206/100k/3950K spare part
   #define TEMP_SENSOR_BED 7
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 100
 
 //===========================================================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/TinyBoy2/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/WITBOX/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 0
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/WITBOX/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/adafruit/ST7565/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 0
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/delta/flsun_kossel_mini/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 1
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/delta/flsun_kossel_mini/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/delta/generic/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 0
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/delta/generic/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/delta/kossel_mini/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 11
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/delta/kossel_mini/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/delta/kossel_pro/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 5
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/delta/kossel_pro/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/delta/kossel_xl/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 5
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/delta/kossel_xl/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/makibox/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 12
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/makibox/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/example_configurations/tvrrug/Round2/Configuration.h

 #define TEMP_SENSOR_1 0
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_3 0
+#define TEMP_SENSOR_4 0
 #define TEMP_SENSOR_BED 5
 
 // Dummy thermistor constant temperature readings, for use with 998 and 999
 #define HEATER_1_MINTEMP 5
 #define HEATER_2_MINTEMP 5
 #define HEATER_3_MINTEMP 5
+#define HEATER_4_MINTEMP 5
 #define BED_MINTEMP 5
 
 // When temperature exceeds max temp, your heater will be switched off.
 #define HEATER_1_MAXTEMP 275
 #define HEATER_2_MAXTEMP 275
 #define HEATER_3_MAXTEMP 275
+#define HEATER_4_MAXTEMP 275
 #define BED_MAXTEMP 150
 
 //===========================================================================
 #define INVERT_E1_DIR false
 #define INVERT_E2_DIR false
 #define INVERT_E3_DIR false
+#define INVERT_E4_DIR false
 
 // @section homing
 

Marlin/example_configurations/tvrrug/Round2/Configuration_adv.h

 #define E1_AUTO_FAN_PIN -1
 #define E2_AUTO_FAN_PIN -1
 #define E3_AUTO_FAN_PIN -1
+#define E4_AUTO_FAN_PIN -1
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 

Marlin/language.h

 #define MSG_H2 "2"
 #define MSG_H3 "3"
 #define MSG_H4 "4"
+#define MSG_H5 "5"
 #define MSG_N1 " 1"
 #define MSG_N2 " 2"
 #define MSG_N3 " 3"
 #define MSG_N4 " 4"
+#define MSG_N5 " 5"
 #define MSG_E1 "E1"
 #define MSG_E2 "E2"
 #define MSG_E3 "E3"
 #define MSG_E4 "E4"
+#define MSG_E5 "E5"
 #define MSG_MOVE_E1 "1"
 #define MSG_MOVE_E2 "2"
 #define MSG_MOVE_E3 "3"
 #define MSG_MOVE_E4 "4"
+#define MSG_MOVE_E5 "5"
 #define MSG_DIAM_E1 " 1"
 #define MSG_DIAM_E2 " 2"
 #define MSG_DIAM_E3 " 3"
 #define MSG_DIAM_E4 " 4"
+#define MSG_DIAM_E5 " 5"
 
 #include INCLUDE_LANGUAGE
 

Marlin/macros.h

 
 #define CEILING(x,y) (((x) + (y) - 1) / (y))
 
-#define MIN3(a, b, c)    min(min(a, b), c)
-#define MIN4(a, b, c, d) min(min(a, b), min(c, d))
-#define MAX3(a, b, c)    max(max(a, b), c)
-#define MAX4(a, b, c, d) max(max(a, b), max(c, d))
+#define MIN3(a, b, c)       min(min(a, b), c)
+#define MIN4(a, b, c, d)    min(MIN3(a, b, c), d)
+#define MIN5(a, b, c, d, e) min(MIN4(a, b, c, d), e)
+#define MAX3(a, b, c)       max(max(a, b), c)
+#define MAX4(a, b, c, d)    max(MAX3(a, b, c), d)
+#define MAX5(a, b, c, d, e) max(MAX4(a, b, c, d), e)
 
 #define UNEAR_ZERO(x) ((x) < 0.000001)
 #define NEAR_ZERO(x) WITHIN(x, -0.000001, 0.000001)

Marlin/pins.h

 #ifndef TEMP_3_PIN
   #define TEMP_3_PIN -1
 #endif
+#ifndef TEMP_4_PIN
+  #define TEMP_4_PIN -1
+#endif
 #ifndef TEMP_BED_PIN
   #define TEMP_BED_PIN -1
 #endif
 #endif
 
 #ifndef MAX_EXTRUDERS
-  #define MAX_EXTRUDERS 4
+  #define MAX_EXTRUDERS 5
 #endif
 
 // Marlin needs to account for pins that equal -1
       #if EXTRUDERS > 4
         #undef _E4_PINS
         #define _E4_PINS E4_STEP_PIN, E4_DIR_PIN, E4_ENABLE_PIN,
-      #endif
-    #endif
-  #endif
-#endif
+      #endif // EXTRUDERS > 4
+    #endif // EXTRUDERS > 3
+  #endif // EXTRUDERS > 2
+#endif // EXTRUDERS > 1
 
 #define _H0_PINS HEATER_0_PIN, E0_AUTO_FAN_PIN, marlinAnalogInputToDigitalPin(TEMP_0_PIN),
 #define _H1_PINS
       #if HOTENDS > 4
         #undef _H4_PINS
         #define _H4_PINS HEATER_4_PIN, marlinAnalogInputToDigitalPin(TEMP_4_PIN),
-      #endif
-    #endif
-  #endif
+      #endif // HOTENDS > 4
+    #endif // HOTENDS > 3
+  #endif // HOTENDS > 2
 #elif ENABLED(MIXING_EXTRUDER)
   #undef _E1_PINS
   #define _E1_PINS E1_STEP_PIN, E1_DIR_PIN, E1_ENABLE_PIN,
       #if MIXING_STEPPERS > 4
         #undef _E4_PINS
         #define _E4_PINS E4_STEP_PIN, E4_DIR_PIN, E4_ENABLE_PIN,
-      #endif
-    #endif
-  #endif
-#endif
+      #endif // MIXING_STEPPERS > 4
+    #endif // MIXING_STEPPERS > 3
+  #endif // MIXING_STEPPERS > 2
+#endif // MIXING_STEPPERS > 1
 
 #define BED_PINS HEATER_BED_PIN, marlinAnalogInputToDigitalPin(TEMP_BED_PIN),
 

Marlin/pins_AZTEEG_X3.h

  * AZTEEG_X3 Arduino Mega with RAMPS v1.4 pin assignments
  */
 
-#if HOTENDS > 2
-  #error "Azteeg X3 supports up to 2 hotends. Comment this line to keep going."
+#if HOTENDS > 2 || E_STEPPERS > 2
+  #error "Azteeg X3 supports up to 2 hotends / E-steppers. Comment out this line to continue."
 #endif
 
 #define BOARD_NAME "Azteeg X3"

Marlin/pins_AZTEEG_X3_PRO.h

  * AZTEEG_X3_PRO (Arduino Mega) pin assignments
  */
 
+#if HOTENDS > 5 || E_STEPPERS > 5
+  #error "Azteeg X3 Pro supports up to 5 hotends / E-steppers. Comment out this line to continue."
+#endif
+
 #define BOARD_NAME "Azteeg X3 Pro"
 
 #include "pins_RAMPS.h"

Marlin/pins_BAM_DICE_DUE.h

  * BAM&DICE Due (Arduino Mega) pin assignments
  */
 
-#if HOTENDS > 2
-  #error "2PrintBeta Due supports up to 2 hotends. Comment this line to keep going."
+#if HOTENDS > 2 || E_STEPPERS > 2
+  #error "2PrintBeta Due supports up to 2 hotends / E-steppers. Comment out this line to continue."
 #endif
 
 #define BOARD_NAME "2PrintBeta Due"

Marlin/pins_FELIX2.h

  * FELIXprinters v2.0/3.0 (RAMPS v1.4) pin assignments
  */
 
-#if HOTENDS > 2
-  #error "Felix 2.0+ supports up to 2 hotends. Comment this line to keep going."
+#if HOTENDS > 2 || E_STEPPERS > 2
+  #error "Felix 2.0+ supports up to 2 hotends / E-steppers. Comment out this line to continue."
 #endif
 
 #define BOARD_NAME "Felix 2.0+"

Marlin/pins_MEGACONTROLLER.h

   #error "Oops!  Make sure you have 'Arduino Mega' selected from the 'Tools -> Boards' menu."
 #endif
 
-#if E_STEPPERS > 2 || HOTENDS > 2
-  #error "Mega Controller supports up to 2 hotends / E-steppers. Comment this line to keep going."
+#if HOTENDS > 2 || E_STEPPERS > 2
+  #error "Mega Controller supports up to 2 hotends / E-steppers. Comment out this line to continue."
 #endif
 
 #define BOARD_NAME "Mega Controller"

Marlin/pins_MINITRONICS.h

   #error "Oops!  Make sure you have 'Minitronics' selected from the 'Tools -> Boards' menu."
 #endif
 
-#if HOTENDS > 2
-  #error "Minitronics supports up to 2 hotends. Comment this line to keep going."
+#if HOTENDS > 2 || E_STEPPERS > 2
+  #error "Minitronics supports up to 2 hotends / E-steppers. Comment out this line to continue."
 #endif
 
 #define BOARD_NAME         "Minitronics v1.0 / v1.1"

Marlin/pins_MKS_13.h

  *  MKS v1.4  (Extruder, Extruder, Fan, Bed)
  */
 
-#if HOTENDS > 2
-  #error "MKS 1.3/1.4 supports up to 2 hotends. Comment this line to keep going."
+#if HOTENDS > 2 || E_STEPPERS > 2
+  #error "MKS 1.3/1.4 supports up to 2 hotends / E-steppers. Comment out this line to continue."
 #endif
 
 #define BOARD_NAME "MKS > v1.3"

Marlin/pins_MKS_BASE.h

  * MKS BASE 1.0 – Arduino Mega2560 with RAMPS v1.4 pin assignments
  */
 
-#if HOTENDS > 2
-  #error "MKS BASE 1.0 supports up to 2 hotends. Comment this line to keep going."
+#if HOTENDS > 2 || E_STEPPERS > 2
+  #error "MKS BASE 1.0 supports up to 2 hotends / E-steppers. Comment out this line to continue."
 #endif
 
 #define BOARD_NAME "MKS BASE 1.0"

Marlin/pins_RUMBA.h

   #error "Oops!  Make sure you have 'Arduino Mega' selected from the 'Tools -> Boards' menu."
 #endif
 
-#if E_STEPPERS > 3 || HOTENDS > 3
-  #error "RUMBA supports up to 3 hotends / E-steppers. Comment this line to keep going."
+#if HOTENDS > 3 || E_STEPPERS > 3
+  #error "RUMBA supports up to 3 hotends / E-steppers. Comment out this line to continue."
 #endif
 
 #define DEFAULT_MACHINE_NAME "Rumba"

Marlin/pins_SAINSMART_2IN1.h

  *  Sainsmart 2-in-1 pin assignments
  */
 
-#if HOTENDS > 2
-  #error "Sainsmart 2-in-1 supports up to 2 hotends. Comment this line to keep going."
+#if HOTENDS > 2 || E_STEPPERS > 2
+  #error "Sainsmart 2-in-1 supports up to 2 hotends / E-steppers. Comment out this line to continue."
 #endif
 
 #define BOARD_NAME "Sainsmart"

Marlin/planner.cpp

               if (g_uc_extruder_last_move[2] == 0) disable_e2();
               #if EXTRUDERS > 3
                 if (g_uc_extruder_last_move[3] == 0) disable_e3();
-              #endif
-            #endif
-          #endif
+                #if EXTRUDERS > 4
+                  if (g_uc_extruder_last_move[4] == 0) disable_e4();
+                #endif // EXTRUDERS > 4
+              #endif // EXTRUDERS > 3
+            #endif // EXTRUDERS > 2
+          #endif // EXTRUDERS > 1
         break;
         #if EXTRUDERS > 1
           case 1:
               if (g_uc_extruder_last_move[2] == 0) disable_e2();
               #if EXTRUDERS > 3
                 if (g_uc_extruder_last_move[3] == 0) disable_e3();
-              #endif
-            #endif
+                #if EXTRUDERS > 4
+                  if (g_uc_extruder_last_move[4] == 0) disable_e4();
+                #endif // EXTRUDERS > 4
+              #endif // EXTRUDERS > 3
+            #endif // EXTRUDERS > 2
           break;
           #if EXTRUDERS > 2
             case 2:
               if (g_uc_extruder_last_move[1] == 0) disable_e1();
               #if EXTRUDERS > 3
                 if (g_uc_extruder_last_move[3] == 0) disable_e3();
+                #if EXTRUDERS > 4
+                  if (g_uc_extruder_last_move[4] == 0) disable_e4();
+                #endif
               #endif
             break;
             #if EXTRUDERS > 3
                 if (g_uc_extruder_last_move[0] == 0) disable_e0();
                 if (g_uc_extruder_last_move[1] == 0) disable_e1();
                 if (g_uc_extruder_last_move[2] == 0) disable_e2();
+                #if EXTRUDERS > 4
+                  if (g_uc_extruder_last_move[4] == 0) disable_e4();
+                #endif
               break;
+              #if EXTRUDERS > 4
+                case 4:
+                  enable_e4();
+                  g_uc_extruder_last_move[4] = (BLOCK_BUFFER_SIZE) * 2;
+                  if (g_uc_extruder_last_move[0] == 0) disable_e0();
+                  if (g_uc_extruder_last_move[1] == 0) disable_e1();
+                  if (g_uc_extruder_last_move[2] == 0) disable_e2();
+                  if (g_uc_extruder_last_move[3] == 0) disable_e3();
+                break;
+              #endif // EXTRUDERS > 4
             #endif // EXTRUDERS > 3
           #endif // EXTRUDERS > 2
         #endif // EXTRUDERS > 1
       enable_e1();
       enable_e2();
       enable_e3();
+      enable_e4();
     #endif
   }
 

Marlin/stepper_indirection.h

   #define E_STEP_WRITE(v) E0_STEP_WRITE(v)
   #define NORM_E_DIR() E0_DIR_WRITE(current_block->active_extruder ?  INVERT_E0_DIR : !INVERT_E0_DIR)
   #define  REV_E_DIR() E0_DIR_WRITE(current_block->active_extruder ? !INVERT_E0_DIR :  INVERT_E0_DIR)
+#elif EXTRUDERS > 4
+  #define E_STEP_WRITE(v) { switch (current_block->active_extruder) { case 0: E0_STEP_WRITE(v); break; case 1: E1_STEP_WRITE(v); break; case 2: E2_STEP_WRITE(v); break; case 3: E3_STEP_WRITE(v); break; case 4: E4_STEP_WRITE(v); } }
+  #define NORM_E_DIR() { switch (current_block->active_extruder) { case 0: E0_DIR_WRITE(!INVERT_E0_DIR); break; case 1: E1_DIR_WRITE(!INVERT_E1_DIR); break; case 2: E2_DIR_WRITE(!INVERT_E2_DIR); break; case 3: E3_DIR_WRITE(!INVERT_E3_DIR); break; case 4: E4_DIR_WRITE(!INVERT_E4_DIR); } }
+  #define REV_E_DIR() { switch (current_block->active_extruder) { case 0: E0_DIR_WRITE(INVERT_E0_DIR); break; case 1: E1_DIR_WRITE(INVERT_E1_DIR); break; case 2: E2_DIR_WRITE(INVERT_E2_DIR); break; case 3: E3_DIR_WRITE(INVERT_E3_DIR); break; case 4: E4_DIR_WRITE(INVERT_E4_DIR); } }
 #elif EXTRUDERS > 3
   #define E_STEP_WRITE(v) { switch (current_block->active_extruder) { case 0: E0_STEP_WRITE(v); break; case 1: E1_STEP_WRITE(v); break; case 2: E2_STEP_WRITE(v); break; case 3: E3_STEP_WRITE(v); } }
   #define NORM_E_DIR() { switch (current_block->active_extruder) { case 0: E0_DIR_WRITE(!INVERT_E0_DIR); break; case 1: E1_DIR_WRITE(!INVERT_E1_DIR); break; case 2: E2_DIR_WRITE(!INVERT_E2_DIR); break; case 3: E3_DIR_WRITE(!INVERT_E3_DIR); } }
   #endif
 #elif ENABLED(MIXING_EXTRUDER)
   #define E_STEP_WRITE(v) NOOP /* not used for mixing extruders! */
-  #if MIXING_STEPPERS > 3
+  #if MIXING_STEPPERS > 4
+    #define En_STEP_WRITE(n,v) { switch (n) { case 0: E0_STEP_WRITE(v); break; case 1: E1_STEP_WRITE(v); break; case 2: E2_STEP_WRITE(v); break; case 3: E3_STEP_WRITE(v); break; case 4: E4_STEP_WRITE(v); } }
+    #define NORM_E_DIR() { E0_DIR_WRITE(!INVERT_E0_DIR); E1_DIR_WRITE(!INVERT_E1_DIR); E2_DIR_WRITE(!INVERT_E2_DIR); E3_DIR_WRITE(!INVERT_E3_DIR); E4_DIR_WRITE(!INVERT_E4_DIR); }
+    #define REV_E_DIR()  { E0_DIR_WRITE( INVERT_E0_DIR); E1_DIR_WRITE( INVERT_E1_DIR); E2_DIR_WRITE( INVERT_E2_DIR); E3_DIR_WRITE( INVERT_E3_DIR); E4_DIR_WRITE( INVERT_E4_DIR); }
+  #elif MIXING_STEPPERS > 3
     #define En_STEP_WRITE(n,v) { switch (n) { case 0: E0_STEP_WRITE(v); break; case 1: E1_STEP_WRITE(v); break; case 2: E2_STEP_WRITE(v); break; case 3: E3_STEP_WRITE(v); } }
     #define NORM_E_DIR() { E0_DIR_WRITE(!INVERT_E0_DIR); E1_DIR_WRITE(!INVERT_E1_DIR); E2_DIR_WRITE(!INVERT_E2_DIR); E3_DIR_WRITE(!INVERT_E3_DIR); }
     #define REV_E_DIR()  { E0_DIR_WRITE( INVERT_E0_DIR); E1_DIR_WRITE( INVERT_E1_DIR); E2_DIR_WRITE( INVERT_E2_DIR); E3_DIR_WRITE( INVERT_E3_DIR); }

Marlin/temperature.cpp

   static void* heater_ttbl_map[2] = {(void*)HEATER_0_TEMPTABLE, (void*)HEATER_1_TEMPTABLE };
   static uint8_t heater_ttbllen_map[2] = { HEATER_0_TEMPTABLE_LEN, HEATER_1_TEMPTABLE_LEN };
 #else
-  static void* heater_ttbl_map[HOTENDS] = ARRAY_BY_HOTENDS((void*)HEATER_0_TEMPTABLE, (void*)HEATER_1_TEMPTABLE, (void*)HEATER_2_TEMPTABLE, (void*)HEATER_3_TEMPTABLE);
-  static uint8_t heater_ttbllen_map[HOTENDS] = ARRAY_BY_HOTENDS(HEATER_0_TEMPTABLE_LEN, HEATER_1_TEMPTABLE_LEN, HEATER_2_TEMPTABLE_LEN, HEATER_3_TEMPTABLE_LEN);
+  static void* heater_ttbl_map[HOTENDS] = ARRAY_BY_HOTENDS((void*)HEATER_0_TEMPTABLE, (void*)HEATER_1_TEMPTABLE, (void*)HEATER_2_TEMPTABLE, (void*)HEATER_3_TEMPTABLE, (void*)HEATER_4_TEMPTABLE);
+  static uint8_t heater_ttbllen_map[HOTENDS] = ARRAY_BY_HOTENDS(HEATER_0_TEMPTABLE_LEN, HEATER_1_TEMPTABLE_LEN, HEATER_2_TEMPTABLE_LEN, HEATER_3_TEMPTABLE_LEN, HEATER_4_TEMPTABLE_LEN);
 #endif
 
 Temperature thermalManager;
 unsigned long Temperature::raw_temp_bed_value = 0;
 
 // Init min and max temp with extreme values to prevent false errors during startup
-int Temperature::minttemp_raw[HOTENDS] = ARRAY_BY_HOTENDS(HEATER_0_RAW_LO_TEMP , HEATER_1_RAW_LO_TEMP , HEATER_2_RAW_LO_TEMP, HEATER_3_RAW_LO_TEMP),
-    Temperature::maxttemp_raw[HOTENDS] = ARRAY_BY_HOTENDS(HEATER_0_RAW_HI_TEMP , HEATER_1_RAW_HI_TEMP , HEATER_2_RAW_HI_TEMP, HEATER_3_RAW_HI_TEMP),
+int Temperature::minttemp_raw[HOTENDS] = ARRAY_BY_HOTENDS(HEATER_0_RAW_LO_TEMP , HEATER_1_RAW_LO_TEMP , HEATER_2_RAW_LO_TEMP, HEATER_3_RAW_LO_TEMP, HEATER_4_RAW_LO_TEMP),
+    Temperature::maxttemp_raw[HOTENDS] = ARRAY_BY_HOTENDS(HEATER_0_RAW_HI_TEMP , HEATER_1_RAW_HI_TEMP , HEATER_2_RAW_HI_TEMP, HEATER_3_RAW_HI_TEMP, HEATER_4_RAW_HI_TEMP),
     Temperature::minttemp[HOTENDS] = { 0 },
     Temperature::maxttemp[HOTENDS] = ARRAY_BY_HOTENDS1(16383);
 
 #if HAS_AUTO_FAN
 
   void Temperature::checkExtruderAutoFans() {
-    const int8_t fanPin[] = { E0_AUTO_FAN_PIN, E1_AUTO_FAN_PIN, E2_AUTO_FAN_PIN, E3_AUTO_FAN_PIN };
-    const int fanBit[] = {
+    constexpr int8_t fanPin[] = { E0_AUTO_FAN_PIN, E1_AUTO_FAN_PIN, E2_AUTO_FAN_PIN, E3_AUTO_FAN_PIN, E4_AUTO_FAN_PIN };
+    constexpr int fanBit[] = {
                     0,
       AUTO_1_IS_0 ? 0 :               1,
       AUTO_2_IS_0 ? 0 : AUTO_2_IS_1 ? 1 :               2,
-      AUTO_3_IS_0 ? 0 : AUTO_3_IS_1 ? 1 : AUTO_3_IS_2 ? 2 : 3
+      AUTO_3_IS_0 ? 0 : AUTO_3_IS_1 ? 1 : AUTO_3_IS_2 ? 2 :               3,
+      AUTO_4_IS_0 ? 0 : AUTO_4_IS_1 ? 1 : AUTO_4_IS_2 ? 2 : AUTO_4_IS_3 ? 3 : 4
     };
     uint8_t fanState = 0;
 
   #if HAS_HEATER_3
     SET_OUTPUT(HEATER_3_PIN);
   #endif
+  #if HAS_HEATER_4
+    SET_OUTPUT(HEATER_3_PIN);
+  #endif
   #if HAS_HEATER_BED
     SET_OUTPUT(HEATER_BED_PIN);
   #endif
   #if HAS_TEMP_3
     ANALOG_SELECT(TEMP_3_PIN);
   #endif
+  #if HAS_TEMP_4
+    ANALOG_SELECT(TEMP_4_PIN);
+  #endif
   #if HAS_TEMP_BED
     ANALOG_SELECT(TEMP_BED_PIN);
   #endif
       SET_OUTPUT(E3_AUTO_FAN_PIN);
     #endif
   #endif
+  #if HAS_AUTO_FAN_4 && !AUTO_4_IS_0 && !AUTO_4_IS_1 && !AUTO_4_IS_2 && !AUTO_4_IS_3
+    #if E4_AUTO_FAN_PIN == FAN1_PIN
+      SET_OUTPUT(E4_AUTO_FAN_PIN);
+      #if ENABLED(FAST_PWM_FAN)
+        setPwmFrequency(E4_AUTO_FAN_PIN, 1); // No prescaling. Pwm frequency = F_CPU/256/8
+      #endif
+    #else
+      SET_OUTPUT(E4_AUTO_FAN_PIN);
+    #endif
+  #endif
 
   // Use timer0 for temperature measurement
   // Interleave temperature interrupt with millies interrupt
         #ifdef HEATER_3_MAXTEMP
           TEMP_MAX_ROUTINE(3);
         #endif
+        #if HOTENDS > 4
+          #ifdef HEATER_4_MINTEMP
+            TEMP_MIN_ROUTINE(4);
+          #endif
+          #ifdef HEATER_4_MAXTEMP
+            TEMP_MAX_ROUTINE(4);
+          #endif
+        #endif // HOTENDS > 4
       #endif // HOTENDS > 3
     #endif // HOTENDS > 2
   #endif // HOTENDS > 1
 
   #if HAS_TEMP_HOTEND
     DISABLE_HEATER(0);
-  #endif
-
-  #if HOTENDS > 1 && HAS_TEMP_1
-    DISABLE_HEATER(1);
-  #endif
-
-  #if HOTENDS > 2 && HAS_TEMP_2
-    DISABLE_HEATER(2);
-  #endif
-
-  #if HOTENDS > 3 && HAS_TEMP_3
-    DISABLE_HEATER(3);
+    #if HOTENDS > 1
+      DISABLE_HEATER(1);
+      #if HOTENDS > 2
+        DISABLE_HEATER(2);
+        #if HOTENDS > 3
+          DISABLE_HEATER(3);
+          #if HOTENDS > 4
+            DISABLE_HEATER(4);
+          #endif // HOTENDS > 4
+        #endif // HOTENDS > 3
+      #endif // HOTENDS > 2
+    #endif // HOTENDS > 1
   #endif
 
   #if HAS_TEMP_BED
       current_temperature_raw[2] = raw_temp_value[2];
       #if HAS_TEMP_3
         current_temperature_raw[3] = raw_temp_value[3];
+        #if HAS_TEMP_4
+          current_temperature_raw[4] = raw_temp_value[4];
+        #endif
       #endif
     #endif
   #endif
       ISR_STATICS(2);
       #if HOTENDS > 3
         ISR_STATICS(3);
-      #endif
-    #endif
-  #endif
+        #if HOTENDS > 4
+          ISR_STATICS(4);
+        #endif // HOTENDS > 4
+      #endif // HOTENDS > 3
+    #endif // HOTENDS > 2
+  #endif // HOTENDS > 1
   #if HAS_HEATER_BED
     ISR_STATICS(BED);
   #endif
           #if HOTENDS > 3
             soft_pwm_3 = (soft_pwm_3 & pwm_mask) + soft_pwm[3];
             WRITE_HEATER_3(soft_pwm_3 > pwm_mask ? HIGH : LOW);
-          #endif
-        #endif
-      #endif
+            #if HOTENDS > 4
+              soft_pwm_4 = (soft_pwm_4 & pwm_mask) + soft_pwm[4];
+              WRITE_HEATER_4(soft_pwm_4 > pwm_mask ? HIGH : LOW);
+            #endif // HOTENDS > 4
+          #endif // HOTENDS > 3
+        #endif // HOTENDS > 2
+      #endif // HOTENDS > 1
 
       #if HAS_HEATER_BED
         soft_pwm_BED = (soft_pwm_BED & pwm_mask) + soft_pwm_bed;
       if (soft_pwm_0 <= pwm_count_tmp) WRITE_HEATER_0(0);
       #if HOTENDS > 1
         if (soft_pwm_1 <= pwm_count_tmp) WRITE_HEATER_1(0);
-      #endif
-      #if HOTENDS > 2
-        if (soft_pwm_2 <= pwm_count_tmp) WRITE_HEATER_2(0);
-      #endif
-      #if HOTENDS > 3
-        if (soft_pwm_3 <= pwm_count_tmp) WRITE_HEATER_3(0);
-      #endif
+        #if HOTENDS > 2
+          if (soft_pwm_2 <= pwm_count_tmp) WRITE_HEATER_2(0);
+          #if HOTENDS > 3
+            if (soft_pwm_3 <= pwm_count_tmp) WRITE_HEATER_3(0);
+            #if HOTENDS > 4
+              if (soft_pwm_4 <= pwm_count_tmp) WRITE_HEATER_4(0);
+            #endif // HOTENDS > 4
+          #endif // HOTENDS > 3
+        #endif // HOTENDS > 2
+      #endif // HOTENDS > 1
 
       #if HAS_HEATER_BED
         if (soft_pwm_BED <= pwm_count_tmp) WRITE_HEATER_BED(0);
 
     if (slow_pwm_count == 0) {
 
-      SLOW_PWM_ROUTINE(0); // EXTRUDER 0
+      SLOW_PWM_ROUTINE(0);
       #if HOTENDS > 1
-        SLOW_PWM_ROUTINE(1); // EXTRUDER 1
+        SLOW_PWM_ROUTINE(1);
         #if HOTENDS > 2
-          SLOW_PWM_ROUTINE(2); // EXTRUDER 2
+          SLOW_PWM_ROUTINE(2);
           #if HOTENDS > 3
-            SLOW_PWM_ROUTINE(3); // EXTRUDER 3
-          #endif
-        #endif
-      #endif
+            SLOW_PWM_ROUTINE(3);
+            #if HOTENDS > 4
+              SLOW_PWM_ROUTINE(4);
+            #endif // HOTENDS > 4
+          #endif // HOTENDS > 3
+        #endif // HOTENDS > 2
+      #endif // HOTENDS > 1
       #if HAS_HEATER_BED
         _SLOW_PWM_ROUTINE(BED, soft_pwm_bed); // BED
       #endif
 
     } // slow_pwm_count == 0
 
-    PWM_OFF_ROUTINE(0); // EXTRUDER 0
+    PWM_OFF_ROUTINE(0);
     #if HOTENDS > 1
-      PWM_OFF_ROUTINE(1); // EXTRUDER 1
+      PWM_OFF_ROUTINE(1);
       #if HOTENDS > 2
-        PWM_OFF_ROUTINE(2); // EXTRUDER 2
+        PWM_OFF_ROUTINE(2);
         #if HOTENDS > 3
-          PWM_OFF_ROUTINE(3); // EXTRUDER 3
-        #endif
-      #endif
-    #endif
+          PWM_OFF_ROUTINE(3);
+          #if HOTENDS > 4
+            PWM_OFF_ROUTINE(4);
+          #endif // HOTENDS > 4
+        #endif // HOTENDS > 3
+      #endif // HOTENDS > 2
+    #endif // HOTENDS > 1
     #if HAS_HEATER_BED
       PWM_OFF_ROUTINE(BED); // BED
     #endif
       slow_pwm_count++;
       slow_pwm_count &= 0x7F;
 
-      // EXTRUDER 0
       if (state_timer_heater_0 > 0) state_timer_heater_0--;
-      #if HOTENDS > 1    // EXTRUDER 1
+      #if HOTENDS > 1
         if (state_timer_heater_1 > 0) state_timer_heater_1--;
-        #if HOTENDS > 2    // EXTRUDER 2
+        #if HOTENDS > 2
           if (state_timer_heater_2 > 0) state_timer_heater_2--;
-          #if HOTENDS > 3    // EXTRUDER 3
+          #if HOTENDS > 3
             if (state_timer_heater_3 > 0) state_timer_heater_3--;
-          #endif
-        #endif
-      #endif
+            #if HOTENDS > 4
+              if (state_timer_heater_4 > 0) state_timer_heater_4--;
+            #endif // HOTENDS > 4
+          #endif // HOTENDS > 3
+        #endif // HOTENDS > 2
+      #endif // HOTENDS > 1
       #if HAS_HEATER_BED
         if (state_timer_heater_BED > 0) state_timer_heater_BED--;
       #endif
     #define START_ADC(pin) ADCSRB = 0; SET_ADMUX_ADCSRA(pin)
   #endif
 
-  // Prepare or measure a sensor, each one every 12th frame
+  // Prepare or measure a sensor, each one every 14th frame
   switch (temp_state) {
     case PrepareTemp_0:
       #if HAS_TEMP_0
       #if HAS_TEMP_3
         raw_temp_value[3] += ADC;
       #endif
+      temp_state = PrepareTemp_4;
+      break;
+
+    case PrepareTemp_4:
+      #if HAS_TEMP_4
+        START_ADC(TEMP_4_PIN);
+      #endif
+      lcd_buttons_update();
+      temp_state = MeasureTemp_4;
+      break;
+    case MeasureTemp_4:
+      #if HAS_TEMP_4
+        raw_temp_value[4] += ADC;
+      #endif
       temp_state = Prepare_FILWIDTH;
       break;
 
     ZERO(raw_temp_value);
     raw_temp_bed_value = 0;
 
+    #define TEMPDIR(N) ((HEATER_##N##_RAW_LO_TEMP) > (HEATER_##N##_RAW_HI_TEMP) ? -1 : 1)
+
     int constexpr temp_dir[] = {
       #if ENABLED(HEATER_0_USES_MAX6675)
          0
-      #elif HEATER_0_RAW_LO_TEMP > HEATER_0_RAW_HI_TEMP
-        -1
       #else
-         1
-      #endif
-      #if HAS_TEMP_1 && HOTENDS > 1
-        #if HEATER_1_RAW_LO_TEMP > HEATER_1_RAW_HI_TEMP
-          , -1
-        #else
-          ,  1
-        #endif
-      #endif
-      #if HAS_TEMP_2 && HOTENDS > 2
-        #if HEATER_2_RAW_LO_TEMP > HEATER_2_RAW_HI_TEMP
-          , -1
-        #else
-          ,  1
-        #endif
-      #endif
-      #if HAS_TEMP_3 && HOTENDS > 3
-        #if HEATER_3_RAW_LO_TEMP > HEATER_3_RAW_HI_TEMP
-          , -1
-        #else
-          ,  1
-        #endif
+        TEMPDIR(0)
       #endif
+      #if HOTENDS > 1
+        , TEMPDIR(1)
+        #if HOTENDS > 2
+          , TEMPDIR(2)
+          #if HOTENDS > 3
+            , TEMPDIR(3)
+            #if HOTENDS > 4
+              , TEMPDIR(4)
+            #endif // HOTENDS > 4
+          #endif // HOTENDS > 3
+        #endif // HOTENDS > 2
+      #endif // HOTENDS > 1
     };
 
     for (uint8_t e = 0; e < COUNT(temp_dir); e++) {

Marlin/temperature.h

       static millis_t next_bed_check_ms;
     #endif
 
-    static unsigned long raw_temp_value[4],
+    static unsigned long raw_temp_value[MAX_EXTRUDERS],
                          raw_temp_bed_value;
 
     // Init min and max temp with extreme values to prevent false errors during startup

Marlin/thermistortable_20.h

   #define HEATER_3_RAW_HI_TEMP 16383
   #define HEATER_3_RAW_LO_TEMP 0
 #endif
+#if (THERMISTORHEATER_4 == 20)
+  #define HEATER_4_RAW_HI_TEMP 16383
+  #define HEATER_4_RAW_LO_TEMP 0
+#endif
 #if (THERMISTORBED == 20)
   #define HEATER_BED_RAW_HI_TEMP 16383
   #define HEATER_BED_RAW_LO_TEMP 0

Marlin/thermistortables.h

 
 #define OVERSAMPLENR 16
 
-#define ANY_THERMISTOR_IS(n) (THERMISTORHEATER_0 == n || THERMISTORHEATER_1 == n || THERMISTORHEATER_2 == n || THERMISTORHEATER_3 == n || THERMISTORBED == n)
+#define ANY_THERMISTOR_IS(n) (THERMISTORHEATER_0 == n || THERMISTORHEATER_1 == n || THERMISTORHEATER_2 == n || THERMISTORHEATER_3 == n || THERMISTORHEATER_4 == n || THERMISTORBED == n)
 
 // Pt1000 and Pt100 handling
 //
   #define HEATER_3_TEMPTABLE_LEN 0
 #endif
 
+#ifdef THERMISTORHEATER_4
+  #define HEATER_4_TEMPTABLE TT_NAME(THERMISTORHEATER_4)
+  #define HEATER_4_TEMPTABLE_LEN COUNT(HEATER_4_TEMPTABLE)
+#elif defined(HEATER_4_USES_THERMISTOR)
+  #error "No heater 4 thermistor table specified"
+#else
+  #define HEATER_4_TEMPTABLE NULL
+  #define HEATER_4_TEMPTABLE_LEN 0
+#endif
+
 #ifdef THERMISTORBED
   #define BEDTEMPTABLE TT_NAME(THERMISTORBED)
   #define BEDTEMPTABLE_LEN COUNT(BEDTEMPTABLE)

Marlin/ultralcd.cpp

    * Watch temperature callbacks
    */
   #if WATCH_HOTENDS
-    #if TEMP_SENSOR_0 != 0
+    #if HAS_TEMP_HOTEND
       void watch_temp_callback_E0() { thermalManager.start_watching_heater(0); }
+      #if HOTENDS > 1
+        void watch_temp_callback_E1() { thermalManager.start_watching_heater(1); }
+        #if HOTENDS > 2
+          void watch_temp_callback_E2() { thermalManager.start_watching_heater(2); }
+          #if HOTENDS > 3
+            void watch_temp_callback_E3() { thermalManager.start_watching_heater(3); }
+            #if HOTENDS > 4
+              void watch_temp_callback_E4() { thermalManager.start_watching_heater(4); }
+            #endif // HOTENDS > 4
+          #endif // HOTENDS > 3
+        #endif // HOTENDS > 2
+      #endif // HOTENDS > 1
     #endif
-    #if HOTENDS > 1 && TEMP_SENSOR_1 != 0
-      void watch_temp_callback_E1() { thermalManager.start_watching_heater(1); }
-    #endif // HOTENDS > 1
-    #if HOTENDS > 2 && TEMP_SENSOR_2 != 0
-      void watch_temp_callback_E2() { thermalManager.start_watching_heater(2); }
-    #endif // HOTENDS > 2
-    #if HOTENDS > 3 && TEMP_SENSOR_3 != 0
-      void watch_temp_callback_E3() { thermalManager.start_watching_heater(3); }
-    #endif // HOTENDS > 3
   #else
-    #if TEMP_SENSOR_0 != 0
+    #if HAS_TEMP_HOTEND
       void watch_temp_callback_E0() {}
+      #if HOTENDS > 1
+        void watch_temp_callback_E1() {}
+        #if HOTENDS > 2
+          void watch_temp_callback_E2() {}
+          #if HOTENDS > 3
+            void watch_temp_callback_E3() {}
+            #if HOTENDS > 4
+              void watch_temp_callback_E4() {}
+            #endif // HOTENDS > 4
+          #endif // HOTENDS > 3
+        #endif // HOTENDS > 2
+      #endif // HOTENDS > 1
     #endif
-    #if HOTENDS > 1 && TEMP_SENSOR_1 != 0
-      void watch_temp_callback_E1() {}
-    #endif // HOTENDS > 1
-    #if HOTENDS > 2 && TEMP_SENSOR_2 != 0
-      void watch_temp_callback_E2() {}
-    #endif // HOTENDS > 2
-    #if HOTENDS > 3 && TEMP_SENSOR_3 != 0
-      void watch_temp_callback_E3() {}
-    #endif // HOTENDS > 3
   #endif
 
   #if WATCH_THE_BED
     // Nozzle [1-4]:
     //
     #if HOTENDS == 1
-      #if TEMP_SENSOR_0 != 0
-        MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE, &thermalManager.target_temperature[0], 0, HEATER_0_MAXTEMP - 15, watch_temp_callback_E0);
-      #endif
+      MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE, &thermalManager.target_temperature[0], 0, HEATER_0_MAXTEMP - 15, watch_temp_callback_E0);
     #else //HOTENDS > 1
-      #if TEMP_SENSOR_0 != 0
-        MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N1, &thermalManager.target_temperature[0], 0, HEATER_0_MAXTEMP - 15, watch_temp_callback_E0);
-      #endif
-      #if TEMP_SENSOR_1 != 0
-        MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N2, &thermalManager.target_temperature[1], 0, HEATER_1_MAXTEMP - 15, watch_temp_callback_E1);
-      #endif
+      MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N1, &thermalManager.target_temperature[0], 0, HEATER_0_MAXTEMP - 15, watch_temp_callback_E0);
+      MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N2, &thermalManager.target_temperature[1], 0, HEATER_1_MAXTEMP - 15, watch_temp_callback_E1);
       #if HOTENDS > 2
-        #if TEMP_SENSOR_2 != 0
-          MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N3, &thermalManager.target_temperature[2], 0, HEATER_2_MAXTEMP - 15, watch_temp_callback_E2);
-        #endif
+        MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N3, &thermalManager.target_temperature[2], 0, HEATER_2_MAXTEMP - 15, watch_temp_callback_E2);
         #if HOTENDS > 3
-          #if TEMP_SENSOR_3 != 0
-            MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N4, &thermalManager.target_temperature[3], 0, HEATER_3_MAXTEMP - 15, watch_temp_callback_E3);
-          #endif
+          MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N4, &thermalManager.target_temperature[3], 0, HEATER_3_MAXTEMP - 15, watch_temp_callback_E3);
+          #if HOTENDS > 4
+            MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N5, &thermalManager.target_temperature[4], 0, HEATER_4_MAXTEMP - 15, watch_temp_callback_E4);
+          #endif // HOTENDS > 4
         #endif // HOTENDS > 3
       #endif // HOTENDS > 2
     #endif // HOTENDS > 1
 
     //
     // Flow:
-    // Flow 1:
-    // Flow 2:
-    // Flow 3:
-    // Flow 4:
+    // Flow [1-5]:
     //
     #if EXTRUDERS == 1
       MENU_ITEM_EDIT(int3, MSG_FLOW, &flow_percentage[0], 10, 999);
         MENU_ITEM_EDIT(int3, MSG_FLOW MSG_N3, &flow_percentage[2], 10, 999);
         #if EXTRUDERS > 3
           MENU_ITEM_EDIT(int3, MSG_FLOW MSG_N4, &flow_percentage[3], 10, 999);
+          #if EXTRUDERS > 4
+            MENU_ITEM_EDIT(int3, MSG_FLOW MSG_N5, &flow_percentage[4], 10, 999);
+          #endif //EXTRUDERS > 4
         #endif //EXTRUDERS > 3
       #endif //EXTRUDERS > 2
     #endif //EXTRUDERS > 1
     }
   #endif
 
-  constexpr int heater_maxtemp[HOTENDS] = ARRAY_BY_HOTENDS(HEATER_0_MAXTEMP, HEATER_1_MAXTEMP, HEATER_2_MAXTEMP, HEATER_3_MAXTEMP);
+  constexpr int heater_maxtemp[HOTENDS] = ARRAY_BY_HOTENDS(HEATER_0_MAXTEMP, HEATER_1_MAXTEMP, HEATER_2_MAXTEMP, HEATER_3_MAXTEMP, HEATER_4_MAXTEMP);
 
   /**
    *
           void lcd_preheat_m1_e3() { _lcd_preheat(3, lcd_preheat_hotend_temp[0], lcd_preheat_bed_temp[0], lcd_preheat_fan_speed[0]); }
           void lcd_preheat_m2_e3() { _lcd_preheat(3, lcd_preheat_hotend_temp[1], lcd_preheat_bed_temp[1], lcd_preheat_fan_speed[1]); }
         #endif
-      #endif
-    #endif
+        #if HOTENDS > 4
+          void lcd_preheat_m1_e4_only() { _lcd_preheat(4, lcd_preheat_hotend_temp[0], -1, lcd_preheat_fan_speed[0]); }
+          void lcd_preheat_m2_e4_only() { _lcd_preheat(4, lcd_preheat_hotend_temp[1], -1, lcd_preheat_fan_speed[1]); }
+          #if TEMP_SENSOR_BED != 0
+            void lcd_preheat_m1_e4() { _lcd_preheat(4, lcd_preheat_hotend_temp[0], lcd_preheat_bed_temp[0], lcd_preheat_fan_speed[0]); }
+            void lcd_preheat_m2_e4() { _lcd_preheat(4, lcd_preheat_hotend_temp[1], lcd_preheat_bed_temp[1], lcd_preheat_fan_speed[1]); }
+          #endif
+        #endif // HOTENDS > 4
+      #endif // HOTENDS > 3
+    #endif // HOTENDS > 2
 
     void lcd_preheat_m1_all() {
       #if HOTENDS > 1
           thermalManager.setTargetHotend(lcd_preheat_hotend_temp[0], 2);
           #if HOTENDS > 3
             thermalManager.setTargetHotend(lcd_preheat_hotend_temp[0], 3);
-          #endif
-        #endif
-      #endif
+            #if HOTENDS > 4
+              thermalManager.setTargetHotend(lcd_preheat_hotend_temp[0], 4);
+            #endif // HOTENDS > 4
+          #endif // HOTENDS > 3
+        #endif // HOTENDS > 2
+      #endif // HOTENDS > 1
       #if TEMP_SENSOR_BED != 0
         lcd_preheat_m1_e0();
       #else
           thermalManager.setTargetHotend(lcd_preheat_hotend_temp[1], 2);
           #if HOTENDS > 3
             thermalManager.setTargetHotend(lcd_preheat_hotend_temp[1], 3);
-          #endif
-        #endif
-      #endif
+            #if HOTENDS > 4
+              thermalManager.setTargetHotend(lcd_preheat_hotend_temp[1], 4);
+            #endif // HOTENDS > 4
+          #endif // HOTENDS > 3
+        #endif // HOTENDS > 2
+      #endif // HOTENDS > 1
       #if TEMP_SENSOR_BED != 0
         lcd_preheat_m2_e0();
       #else
             #else
               MENU_ITEM(function, MSG_PREHEAT_1_N MSG_H4, lcd_preheat_m1_e3_only);
             #endif
-          #endif
-        #endif
+            #if HOTENDS > 4
+              #if TEMP_SENSOR_BED != 0
+                MENU_ITEM(function, MSG_PREHEAT_1_N MSG_H5, lcd_preheat_m1_e4);
+                MENU_ITEM(function, MSG_PREHEAT_1_END " " MSG_E5, lcd_preheat_m1_e4_only);
+              #else
+                MENU_ITEM(function, MSG_PREHEAT_1_N MSG_H5, lcd_preheat_m1_e4_only);
+              #endif
+            #endif // HOTENDS > 4
+          #endif // HOTENDS > 3
+        #endif // HOTENDS > 2
         MENU_ITEM(function, MSG_PREHEAT_1_ALL, lcd_preheat_m1_all);
-      #endif
+      #endif // HOTENDS > 1
       #if TEMP_SENSOR_BED != 0
         MENU_ITEM(function, MSG_PREHEAT_1_BEDONLY, lcd_preheat_m1_bedonly);
       #endif
             #else
               MENU_ITEM(function, MSG_PREHEAT_2_N MSG_H4, lcd_preheat_m2_e3_only);
             #endif
-          #endif
-        #endif
+            #if HOTENDS > 4
+              #if TEMP_SENSOR_BED != 0
+                MENU_ITEM(function, MSG_PREHEAT_2_N MSG_H5, lcd_preheat_m2_e4);
+                MENU_ITEM(function, MSG_PREHEAT_2_END " " MSG_E5, lcd_preheat_m2_e4_only);
+              #else
+                MENU_ITEM(function, MSG_PREHEAT_2_N MSG_H5, lcd_preheat_m2_e4_only);
+              #endif
+            #endif // HOTENDS > 4
+          #endif // HOTENDS > 3
+        #endif // HOTENDS > 2
         MENU_ITEM(function, MSG_PREHEAT_2_ALL, lcd_preheat_m2_all);
-      #endif
+      #endif // HOTENDS > 1
       #if TEMP_SENSOR_BED != 0
         MENU_ITEM(function, MSG_PREHEAT_2_BEDONLY, lcd_preheat_m2_bedonly);
       #endif
       PID_PARAM(Kd, e) = scalePID_d(raw_Kd);
       thermalManager.updatePID();
     }
-    #define _PIDTEMP_BASE_FUNCTIONS(eindex) \
-      void copy_and_scalePID_i_E ## eindex() { copy_and_scalePID_i(eindex); } \
-      void copy_and_scalePID_d_E ## eindex() { copy_and_scalePID_d(eindex); }
+    #define _PIDTEMP_BASE_FUNCTIONS(N) \
+      void copy_and_scalePID_i_E ## N() { copy_and_scalePID_i(N); } \
+      void copy_and_scalePID_d_E ## N() { copy_and_scalePID_d(N); }
 
     #if ENABLED(PID_AUTOTUNE_MENU)
-      #define _PIDTEMP_FUNCTIONS(eindex) \
-        _PIDTEMP_BASE_FUNCTIONS(eindex); \
-        void lcd_autotune_callback_E ## eindex() { _lcd_autotune(eindex); }
+      #define _PIDTEMP_FUNCTIONS(N) \
+        _PIDTEMP_BASE_FUNCTIONS(N); \
+        void lcd_autotune_callback_E ## N() { _lcd_autotune(N); }
     #else
-      #define _PIDTEMP_FUNCTIONS(eindex) _PIDTEMP_BASE_FUNCTIONS(eindex)
+      #define _PIDTEMP_FUNCTIONS(N) _PIDTEMP_BASE_FUNCTIONS(N)
     #endif
 
     _PIDTEMP_FUNCTIONS(0)
           _PIDTEMP_FUNCTIONS(2)
           #if HOTENDS > 3
             _PIDTEMP_FUNCTIONS(3)
-          #endif //HOTENDS > 3
-        #endif //HOTENDS > 2
-      #endif //HOTENDS > 1
-    #endif //PID_PARAMS_PER_HOTEND
+            #if HOTENDS > 4
+              _PIDTEMP_FUNCTIONS(4)
+            #endif // HOTENDS > 4
+          #endif // HOTENDS > 3
+        #endif // HOTENDS > 2
+      #endif // HOTENDS > 1
+    #endif // PID_PARAMS_PER_HOTEND
 
-  #endif //PIDTEMP
+  #endif // PIDTEMP
 
   /**
    *
 
     //
     // Nozzle:
-    // Nozzle [1-4]:
+    // Nozzle [1-5]:
     //
     #if HOTENDS == 1
-      #if TEMP_SENSOR_0 != 0
-        MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE, &thermalManager.target_temperature[0], 0, HEATER_0_MAXTEMP - 15, watch_temp_callback_E0);
-      #endif
-    #else //HOTENDS > 1
-      #if TEMP_SENSOR_0 != 0
-        MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N1, &thermalManager.target_temperature[0], 0, HEATER_0_MAXTEMP - 15, watch_temp_callback_E0);
-      #endif
-      #if TEMP_SENSOR_1 != 0
-        MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N2, &thermalManager.target_temperature[1], 0, HEATER_1_MAXTEMP - 15, watch_temp_callback_E1);
-      #endif
+      MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE, &thermalManager.target_temperature[0], 0, HEATER_0_MAXTEMP - 15, watch_temp_callback_E0);
+    #else // HOTENDS > 1
+      MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N1, &thermalManager.target_temperature[0], 0, HEATER_0_MAXTEMP - 15, watch_temp_callback_E0);
+      MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N2, &thermalManager.target_temperature[1], 0, HEATER_1_MAXTEMP - 15, watch_temp_callback_E1);
       #if HOTENDS > 2
-        #if TEMP_SENSOR_2 != 0
-          MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N3, &thermalManager.target_temperature[2], 0, HEATER_2_MAXTEMP - 15, watch_temp_callback_E2);
-        #endif
+        MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N3, &thermalManager.target_temperature[2], 0, HEATER_2_MAXTEMP - 15, watch_temp_callback_E2);
         #if HOTENDS > 3
-          #if TEMP_SENSOR_3 != 0
-            MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N4, &thermalManager.target_temperature[3], 0, HEATER_3_MAXTEMP - 15, watch_temp_callback_E3);
-          #endif
+          MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N4, &thermalManager.target_temperature[3], 0, HEATER_3_MAXTEMP - 15, watch_temp_callback_E3);
+          #if HOTENDS > 4
+            MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(int3, MSG_NOZZLE MSG_N5, &thermalManager.target_temperature[4], 0, HEATER_4_MAXTEMP - 15, watch_temp_callback_E4);
+          #endif // HOTENDS > 4
         #endif // HOTENDS > 3
       #endif // HOTENDS > 2
     #endif // HOTENDS > 1
           PID_MENU_ITEMS(" " MSG_E3, 2);
           #if HOTENDS > 3
             PID_MENU_ITEMS(" " MSG_E4, 3);
-          #endif //HOTENDS > 3
-        #endif //HOTENDS > 2
-      #else //!PID_PARAMS_PER_HOTEND || HOTENDS == 1
+            #if HOTENDS > 4
+              PID_MENU_ITEMS(" " MSG_E5, 4);
+            #endif // HOTENDS > 4
+          #endif // HOTENDS > 3
+        #endif // HOTENDS > 2
+      #else // !PID_PARAMS_PER_HOTEND || HOTENDS == 1
         PID_MENU_ITEMS("", 0);
-      #endif //!PID_PARAMS_PER_HOTEND || HOTENDS == 1
+      #endif // !PID_PARAMS_PER_HOTEND || HOTENDS == 1
 
     #endif //PIDTEMP
 
   }
 
   void _lcd_control_temperature_preheat_settings_menu(uint8_t material) {
-    #if HOTENDS > 3
+    #if HOTENDS > 4
+      #define MINTEMP_ALL MIN5(HEATER_0_MINTEMP, HEATER_1_MINTEMP, HEATER_2_MINTEMP, HEATER_3_MINTEMP, HEATER_4_MINTEMP)
+      #define MAXTEMP_ALL MAX5(HEATER_0_MAXTEMP, HEATER_1_MAXTEMP, HEATER_2_MAXTEMP, HEATER_3_MAXTEMP, HEATER_4_MAXTEMP)
+    #elif HOTENDS > 3
       #define MINTEMP_ALL MIN4(HEATER_0_MINTEMP, HEATER_1_MINTEMP, HEATER_2_MINTEMP, HEATER_3_MINTEMP)
       #define MAXTEMP_ALL MAX4(HEATER_0_MAXTEMP, HEATER_1_MAXTEMP, HEATER_2_MAXTEMP, HEATER_3_MAXTEMP)
     #elif HOTENDS > 2
     if (volumetric_enabled) {
       #if EXTRUDERS == 1
         MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(float43, MSG_FILAMENT_DIAM, &filament_size[0], 1.5, 3.25, calculate_volumetric_multipliers);
-      #else //EXTRUDERS > 1
+      #else // EXTRUDERS > 1
         MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(float43, MSG_FILAMENT_DIAM MSG_DIAM_E1, &filament_size[0], 1.5, 3.25, calculate_volumetric_multipliers);
         MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(float43, MSG_FILAMENT_DIAM MSG_DIAM_E2, &filament_size[1], 1.5, 3.25, calculate_volumetric_multipliers);
         #if EXTRUDERS > 2
           MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(float43, MSG_FILAMENT_DIAM MSG_DIAM_E3, &filament_size[2], 1.5, 3.25, calculate_volumetric_multipliers);
           #if EXTRUDERS > 3
             MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(float43, MSG_FILAMENT_DIAM MSG_DIAM_E4, &filament_size[3], 1.5, 3.25, calculate_volumetric_multipliers);
-          #endif //EXTRUDERS > 3
-        #endif //EXTRUDERS > 2
-      #endif //EXTRUDERS > 1
+            #if EXTRUDERS > 4
+              MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(float43, MSG_FILAMENT_DIAM MSG_DIAM_E5, &filament_size[4], 1.5, 3.25, calculate_volumetric_multipliers);
+            #endif // EXTRUDERS > 4
+          #endif // EXTRUDERS > 3
+        #endif // EXTRUDERS > 2
+      #endif // EXTRUDERS > 1
     }
 
     END_MENU();