Implement nozzle reheating on timeout via display

- Raise nozzle timeout to 10 minutes
- Use continue button as reheat trigger
- Manage nozzle_timed_out variable via display
- Add PausedByNozzleTimeout flag to enter correct routine on display
- Bump version to 1.4.3

Marlin/AnycubicTFT.cpp

@@ -33,6 +33,7 @@
 #include "stepper.h"
 #include "serial.h"
 #include "printcounter.h"
+#include "macros.h"
 
 #ifdef ANYCUBIC_TFT_MODEL
 #include "AnycubicTFT.h"
@@ -137,7 +138,7 @@ void AnycubicTFTClass::KillTFT()
 
 void AnycubicTFTClass::StartPrint(){
   if (TFTstate==ANYCUBIC_TFT_STATE_SDPAUSE) { // resuming from SD pause
-                if((!PausedByRunout) && (!PausedByFilamentChange)) // was that a regular pause?
+    if((!PausedByRunout) && (!PausedByFilamentChange) && (!PausedByNozzleTimeout)) // was that a regular pause?
     {
       enqueue_and_echo_commands_P(PSTR("G91")); // relative mode
       enqueue_and_echo_commands_P(PSTR("G1 Z-10 F240")); // lower nozzle again
@@ -147,11 +148,11 @@ void AnycubicTFTClass::StartPrint(){
   }
   starttime=millis();
   #ifdef SDSUPPORT
-        if((!PausedByRunout) && (!PausedByFilamentChange)) // was that a regular pause?
+    if((!PausedByRunout) && (!PausedByFilamentChange) && (!PausedByNozzleTimeout)) // was that a regular pause?
     {
       card.startFileprint(); // start or resume regularly
     }
-        else if((PausedByRunout) && (!PausedByFilamentChange)) // resuming from a pause that was caused by filament runout
+    else if((PausedByRunout) && (!PausedByFilamentChange) && (!PausedByNozzleTimeout)) // resuming from a pause that was caused by filament runout
     {
       enqueue_and_echo_commands_P(PSTR("M24")); // unpark nozzle and resume
       #ifdef ANYCUBIC_TFT_DEBUG
@@ -162,19 +163,30 @@ void AnycubicTFTClass::StartPrint(){
         SERIAL_ECHOLNPGM("DEBUG: Filament Pause Flag cleared");
       #endif
     }
-        else if((!PausedByRunout) && (PausedByFilamentChange)) // was M600 called?
+    else if((!PausedByRunout) && (PausedByFilamentChange) && (!PausedByNozzleTimeout)) // was M600 called and the nozzle is not timed out?
     {
-                FilamentChangeResume(); // enter M108 routine
       #ifdef ANYCUBIC_TFT_DEBUG
         SERIAL_ECHOLNPGM("DEBUG: Start M108 routine");
       #endif
+      FilamentChangeResume(); // enter M108 routine
       PausedByFilamentChange=false; // clear flag
       #ifdef ANYCUBIC_TFT_DEBUG
         SERIAL_ECHOLNPGM("DEBUG: Filament Change Flag cleared");
       #endif
     }
   #endif
+  if (!PausedByNozzleTimeout) {
     TFTstate=ANYCUBIC_TFT_STATE_SDPRINT;
+  } else {
+    TFTstate=ANYCUBIC_TFT_STATE_SDPAUSE_REQ;
+    #ifdef ANYCUBIC_TFT_DEBUG
+      SERIAL_ECHOLNPGM("DEBUG: Set Pause again because of timeout");
+    #endif
+    PausedByNozzleTimeout=false;
+    #ifdef ANYCUBIC_TFT_DEBUG
+      SERIAL_ECHOLNPGM("DEBUG: Nozzle timeout flag cleared");
+    #endif
+  }
 }
 
 void AnycubicTFTClass::PausePrint(){
@@ -222,55 +234,52 @@ void AnycubicTFTClass::PausePrint(){
 }
 
 void AnycubicTFTClass::StopPrint(){
+
   #ifdef SDSUPPORT
     card.stopSDPrint();
   #endif
   clear_command_queue();
-        if((current_position[Z_AXIS]<150))
-        {
-                enqueue_and_echo_commands_P(PSTR("G91"));
-                enqueue_and_echo_commands_P(PSTR("G1 Z20 F240"));
-                enqueue_and_echo_commands_P(PSTR("G90"));
-        }
-        else if ((current_position[Z_AXIS]<190))
-        {
-                enqueue_and_echo_commands_P(PSTR("G91"));
-                enqueue_and_echo_commands_P(PSTR("G1 Z10 F240"));
-                enqueue_and_echo_commands_P(PSTR("G90"));
-        }
-        else if ((current_position[Z_AXIS]<200))
-        {
-                enqueue_and_echo_commands_P(PSTR("G91"));
-                enqueue_and_echo_commands_P(PSTR("G1 Z5 F240"));
-                enqueue_and_echo_commands_P(PSTR("G90"));
-        }
-        else if ((current_position[Z_AXIS]>=200))
-        {
-                enqueue_and_echo_commands_P(PSTR("G91"));
-                enqueue_and_echo_commands_P(PSTR("G1 Z1 F240"));
-                enqueue_and_echo_commands_P(PSTR("G90"));
-        }
   quickstop_stepper();
   print_job_timer.stop();
   thermalManager.disable_all_heaters();
+  if((current_position[Z_AXIS]<150))
+  {
+    enqueue_and_echo_commands_P(PSTR("G91\nG1 Z20 F240\nG90"));
+  }
+  else if ((current_position[Z_AXIS]<190))
+  {
+    enqueue_and_echo_commands_P(PSTR("G91\nG1 Z10 F240\nG90"));
+  }
+  else if ((current_position[Z_AXIS]<200))
+  {
+    enqueue_and_echo_commands_P(PSTR("G91\nG1 Z5 F240\nG90"));
+  }
+  else if ((current_position[Z_AXIS]>=200))
+  {
+    enqueue_and_echo_commands_P(PSTR("G91\nG1 Z1 F240\G90"));
+  }
   #if FAN_COUNT > 0
     for (uint8_t i = 0; i < FAN_COUNT; i++) fanSpeeds[i] = 0;
   #endif
   TFTstate=ANYCUBIC_TFT_STATE_SDSTOP_REQ;
+  enqueue_and_echo_commands_P(PSTR("M27")); // force report of SD status
 }
 
 void AnycubicTFTClass::FilamentChangeResume(){
   enqueue_and_echo_commands_P(PSTR("M108")); // call M108 to break out of M600 pause
-        HOTEND_LOOP() thermalManager.reset_heater_idle_timer(e); // resume heating if timed out
+  #ifdef ANYCUBIC_TFT_DEBUG
+    SERIAL_ECHOLNPGM("DEBUG: M108 called");
+  #endif
   wait_for_heatup = false;
   wait_for_user = false; // remove waiting flags
-        // TFTstate=ANYCUBIC_TFT_STATE_SDPRINT;
+  card.startFileprint(); // resume with proper progress state
   #ifdef ANYCUBIC_TFT_DEBUG
-        SERIAL_ECHOLNPGM("DEBUG: M108 Resume called");
+    SERIAL_ECHOLNPGM("DEBUG: M108 Resume done");
   #endif
 }
 
 void AnycubicTFTClass::FilamentChangePause(){
+  PausedByFilamentChange=true;
   enqueue_and_echo_commands_P(PSTR("M600"));
   TFTstate=ANYCUBIC_TFT_STATE_SDPAUSE_REQ; // set TFT state to paused
   #ifdef ANYCUBIC_TFT_DEBUG
@@ -278,6 +287,24 @@ void AnycubicTFTClass::FilamentChangePause(){
   #endif
 }
 
+void AnycubicTFTClass::ReheatNozzle(){
+  #ifdef ANYCUBIC_TFT_DEBUG
+    SERIAL_ECHOLNPGM("DEBUG: Send reheat M108");
+  #endif
+  enqueue_and_echo_commands_P(PSTR("M108"));
+  #ifdef ANYCUBIC_TFT_DEBUG
+    SERIAL_ECHOLNPGM("DEBUG: Resume heating");
+  #endif
+  HOTEND_LOOP() thermalManager.reset_heater_idle_timer(e); // resume heating if timed out
+  #ifdef ANYCUBIC_TFT_DEBUG
+    SERIAL_ECHOLNPGM("DEBUG: Clear flags");
+  #endif
+  nozzle_timed_out = false;
+  wait_for_user = false;
+  wait_for_heatup = false;
+  TFTstate=ANYCUBIC_TFT_STATE_SDPAUSE_REQ;
+}
+
 
 float AnycubicTFTClass::CodeValue()
 {
@@ -302,10 +329,10 @@ void AnycubicTFTClass::HandleSpecialMenu()
     enqueue_and_echo_commands_P(PSTR("M303 E-1 S60 C6 U1"));
   } else if (strcmp(SelectedDirectory, "<save eeprom>")==0) {
     SERIAL_PROTOCOLLNPGM("Special Menu: Save EEPROM");
-                enqueue_and_echo_commands_P(PSTR("M500"));
+    enqueue_and_echo_commands_P(PSTR("M500\nM300 S1108 P105\nM300 S1661 P210"));
   } else if (strcmp(SelectedDirectory, "<load fw defaults>")==0) {
     SERIAL_PROTOCOLLNPGM("Special Menu: Load FW Defaults");
-                enqueue_and_echo_commands_P(PSTR("M502"));
+    enqueue_and_echo_commands_P(PSTR("M502\nM300 S1661 P105\nM300 S1108 P210"));
   } else if (strcmp(SelectedDirectory, "<preheat bed>")==0) {
     SERIAL_PROTOCOLLNPGM("Special Menu: Preheat Bed");
     enqueue_and_echo_commands_P(PSTR("M140 S60"));
@@ -329,7 +356,6 @@ void AnycubicTFTClass::HandleSpecialMenu()
     enqueue_and_echo_commands_P(PSTR("G91\nG1 Z-0.1\nG90"));
   } else if (strcmp(SelectedDirectory, "<filamentchange pause>")==0) {
     SERIAL_PROTOCOLLNPGM("Special Menu: FilamentChange Pause");
-                PausedByFilamentChange=true;
     FilamentChangePause();
   } else if (strcmp(SelectedDirectory, "<filamentchange resume>")==0) {
     SERIAL_PROTOCOLLNPGM("Special Menu: FilamentChange Resume");
@@ -544,7 +570,7 @@ void AnycubicTFTClass::StateHandler()
       #ifdef SDSUPPORT
         if((!card.sdprinting) && (!planner.movesplanned())) {
           // We have to wait until the sd card printing has been settled
-                        if((!PausedByRunout) && (!PausedByFilamentChange))
+          if((!PausedByRunout) && (!PausedByFilamentChange) && (!PausedByNozzleTimeout))
           {
             #ifdef ANYCUBIC_TFT_DEBUG
               SERIAL_ECHOLNPGM("DEBUG: Regular Pause requested");
@@ -605,10 +631,26 @@ void AnycubicTFTClass::FilamentRunout()
 
     if(FilamentTestStatus>FilamentTestLastStatus)
     {
-                FilamentRunoutCounter++;
+      // something changed! save current timestamp.
-                if(FilamentRunoutCounter>=31600)
+      const millis_t fil_ms = millis();
-                {
+      static millis_t fil_delay;
-                        FilamentRunoutCounter=0;
+
+      // since this is inside a loop, only set delay time once
+      if (FilamentSetMillis){
+        #ifdef ANYCUBIC_TFT_DEBUG
+          SERIAL_ECHOLNPGM("DEBUG: Set filament trigger time");
+        #endif
+        // set the delayed timestamp to 3000ms later
+        fil_delay = fil_ms + 3000UL;
+        // this doesn't need to run until the filament is recovered again
+        FilamentSetMillis=false;
+      }
+
+      // have three seconds passed?
+      if ((FilamentTestStatus>FilamentTestLastStatus) && (fil_ms>fil_delay)) {
+        #ifdef ANYCUBIC_TFT_DEBUG
+          SERIAL_ECHOLNPGM("DEBUG: 3000ms delay done");
+        #endif
         #ifdef SDSUPPORT
           if((card.sdprinting==true))
           {
@@ -620,21 +662,20 @@ void AnycubicTFTClass::FilamentRunout()
           }
           else if((card.sdprinting==false))
           {
-#endif
           ANYCUBIC_SERIAL_PROTOCOLPGM("J15"); //J15 FILAMENT LACK
           ANYCUBIC_SERIAL_ENTER();
           #ifdef ANYCUBIC_TFT_DEBUG
             SERIAL_ECHOLNPGM("TFT Serial Debug: Filament runout... J15");
           #endif
-#ifdef SDSUPPORT
+          FilamentTestLastStatus=FilamentTestStatus;
           }
         #endif
-                        FilamentTestLastStatus=FilamentTestStatus;
       }
     }
     else if(FilamentTestStatus!=FilamentTestLastStatus)
     {
-                FilamentRunoutCounter=0;
+      // set the timestamps on the next loop again
+      FilamentSetMillis=true;
       FilamentTestLastStatus=FilamentTestStatus;
       #ifdef ANYCUBIC_TFT_DEBUG
         SERIAL_ECHOLNPGM("TFT Serial Debug: Filament runout recovered");
@@ -805,6 +846,9 @@ void AnycubicTFTClass::GetCommandFromTFT()
                   SERIAL_ECHOLNPGM("TFT Serial Debug: SD print started... J04");
                 #endif
               }
+              if (nozzle_timed_out) {
+                ReheatNozzle();
+              }
             #endif
             break;
           case 11: // A11 STOP SD PRINT

Marlin/AnycubicTFT.h

@@ -58,6 +58,7 @@ public:
   char TFTstate=ANYCUBIC_TFT_STATE_IDLE;
   bool PausedByRunout=false;
   bool PausedByFilamentChange=false;
+  bool PausedByNozzleTimeout=false;
 
 private:
   char TFTcmdbuffer[TFTBUFSIZE][TFT_MAX_CMD_SIZE];
@@ -100,6 +101,7 @@ private:
   void HandleSpecialMenu();
   void FilamentChangePause();
   void FilamentChangeResume();
+  void ReheatNozzle();
 
   char     SelectedDirectory[30];
   uint8_t  SpecialMenu=false;
@@ -107,7 +109,8 @@ private:
 #if ENABLED(ANYCUBIC_FILAMENT_RUNOUT_SENSOR)
   char FilamentTestStatus=false;
   char FilamentTestLastStatus=false;
-  long FilamentRunoutCounter=0;
+  bool FilamentSetMillis=true;
+
 #endif
 };
 

Marlin/Configuration_adv.h

@@ -1009,7 +1009,7 @@
   #define FILAMENT_UNLOAD_DELAY             5000  // (ms) Delay for the filament to cool after retract.
   #define FILAMENT_UNLOAD_PURGE_LENGTH         8  // (mm) An unretract is done, then this length is purged.
 
-  #define PAUSE_PARK_NOZZLE_TIMEOUT          300  // (seconds) Time limit before the nozzle is turned off for safety.
+  #define PAUSE_PARK_NOZZLE_TIMEOUT          600  // (seconds) Time limit before the nozzle is turned off for safety.
   #define FILAMENT_CHANGE_ALERT_BEEPS         10  // Number of alert beeps to play when a response is needed.
   #define PAUSE_PARK_NO_STEPPER_TIMEOUT           // Enable for XYZ steppers to stay powered on during filament change.
 

Marlin/Marlin.h

@@ -271,6 +271,9 @@ FORCE_INLINE bool all_axes_known() { return (axis_known_position & xyz_bits) ==
 
 extern volatile bool wait_for_heatup;
 
+// Making sure this flag can be cleared by the Anycubic display
+extern volatile bool nozzle_timed_out;
+
 #if HAS_RESUME_CONTINUE
   extern volatile bool wait_for_user;
 #endif

Marlin/Marlin_main.cpp

@@ -519,6 +519,9 @@ static bool relative_mode; // = false;
 // For M109 and M190, this flag may be cleared (by M108) to exit the wait loop
 volatile bool wait_for_heatup = true;
 
+// Making sure this flag can be cleared by the Anycubic display
+volatile bool nozzle_timed_out = false;
+
 // For M0/M1, this flag may be cleared (by M108) to exit the wait-for-user loop
 #if HAS_RESUME_CONTINUE
   volatile bool wait_for_user; // = false;
@@ -7213,7 +7216,11 @@ inline void gcode_M17() {
    * Used by M125 and M600
    */
   static void wait_for_filament_reload(const int8_t max_beep_count=0) {
-    bool nozzle_timed_out = false;
+    nozzle_timed_out = false;
+    nozzle_timed_out = false;
+    #ifdef ANYCUBIC_TFT_MODEL
+      AnycubicTFT.PausedByNozzleTimeout = false;
+    #endif
 
     #if ENABLED(ULTIPANEL)
       lcd_advanced_pause_show_message(ADVANCED_PAUSE_MESSAGE_INSERT);
@@ -7246,6 +7253,14 @@ inline void gcode_M17() {
           nozzle_timed_out |= thermalManager.is_heater_idle(e);
 
       if (nozzle_timed_out) {
+
+        #ifdef ANYCUBIC_TFT_MODEL
+          AnycubicTFT.PausedByNozzleTimeout=true;
+          #ifdef ANYCUBIC_TFT_DEBUG
+            SERIAL_ECHOLNPGM("DEBUG: Nozzle timeout flag set");
+          #endif
+        #endif
+
         #if ENABLED(ULTIPANEL)
           lcd_advanced_pause_show_message(ADVANCED_PAUSE_MESSAGE_CLICK_TO_HEAT_NOZZLE);
         #endif
@@ -7287,6 +7302,9 @@ inline void gcode_M17() {
 
         wait_for_user = true; // Wait for user to load filament
         nozzle_timed_out = false;
+        #ifdef ANYCUBIC_TFT_DEBUG
+          AnycubicTFT.PausedByNozzleTimeout = false;
+        #endif
 
         #if HAS_BUZZER
           filament_change_beep(max_beep_count, true);
@@ -7320,7 +7338,11 @@ inline void gcode_M17() {
     if (!did_pause_print) return;
 
     // Re-enable the heaters if they timed out
-    bool nozzle_timed_out = false;
+    nozzle_timed_out = false;
+    #ifdef ANYCUBIC_TFT_MODEL
+      AnycubicTFT.PausedByNozzleTimeout = false;
+    #endif
+
     HOTEND_LOOP() {
       nozzle_timed_out |= thermalManager.is_heater_idle(e);
       thermalManager.reset_heater_idle_timer(e);
@@ -10992,6 +11014,23 @@ inline void gcode_M502() {
    *  Default values are used for omitted arguments.
    */
   inline void gcode_M600() {
+
+    #ifdef SDSUPPORT
+      if (card.sdprinting) { // are we printing from sd?
+        #ifdef ANYCUBIC_TFT_DEBUG
+            SERIAL_ECHOLNPGM("DEBUG: Enter M600 TFTstate routine");
+        #endif
+        AnycubicTFT.TFTstate=ANYCUBIC_TFT_STATE_SDPAUSE_REQ; // enter correct display state to show resume button
+        #ifdef ANYCUBIC_TFT_DEBUG
+            SERIAL_ECHOLNPGM("DEBUG: Set TFTstate to SDPAUSE_REQ");
+        #endif
+        AnycubicTFT.PausedByFilamentChange=true; // set flag to ensure correct resume routine gets executed
+        #ifdef ANYCUBIC_TFT_DEBUG
+            SERIAL_ECHOLNPGM("DEBUG: Set filament change flag");
+        #endif
+      }
+    #endif
+
     point_t park_point = NOZZLE_PARK_POINT;
 
     if (get_target_extruder_from_command(600)) return;
@@ -11054,19 +11093,6 @@ inline void gcode_M502() {
     const bool job_running = print_job_timer.isRunning();
 
     if (pause_print(retract, park_point, unload_length, true)) {
-      #ifdef SDSUPPORT
-        #ifdef ANYCUBIC_TFT_DEBUG
-            SERIAL_ECHOLNPGM("DEBUG: Enter TFTstate routine");
-        #endif
-        AnycubicTFT.TFTstate=ANYCUBIC_TFT_STATE_SDPAUSE_REQ; // enter correct display state to show resume button
-        #ifdef ANYCUBIC_TFT_DEBUG
-            SERIAL_ECHOLNPGM("DEBUG: Set TFTState to SDPAUSE_REQ");
-        #endif
-        AnycubicTFT.PausedByFilamentChange=true; // set flag to ensure correct resume routine gets executed
-        #ifdef ANYCUBIC_TFT_DEBUG
-            SERIAL_ECHOLNPGM("DEBUG: Set filament change flag");
-        #endif
-      #endif
       wait_for_filament_reload(beep_count);
       resume_print(slow_load_length, fast_load_length, ADVANCED_PAUSE_PURGE_LENGTH, beep_count);
     }
@@ -15139,7 +15165,6 @@ void setup() {
   SERIAL_ECHOPGM(MSG_MARLIN);
   SERIAL_CHAR(' ');
   SERIAL_ECHOLNPGM(SHORT_BUILD_VERSION);
-  SERIAL_CHAR(' ');
   SERIAL_ECHOPGM(MSG_MARLIN_AI3M);
   SERIAL_CHAR(' ');
   SERIAL_ECHOLNPGM(CUSTOM_BUILD_VERSION);

Marlin/Version.h

@@ -41,7 +41,7 @@
    * Defines the version of the Marlin-AI3M build. Not to be confused with
    * Marlin's own build number, e.g. 1.1.9.
    */
-  #define CUSTOM_BUILD_VERSION "v1.4.1"
+  #define CUSTOM_BUILD_VERSION "v1.4.3"
 
   /**
    * Verbose version identifier which should contain a reference to the location
@@ -54,7 +54,7 @@
    * here we define this default string as the date where the latest release
    * version was tagged.
    */
-  #define STRING_DISTRIBUTION_DATE "2019-02-23"
+  #define STRING_DISTRIBUTION_DATE "2019-03-06"
 
   /**
    * Required minimum Configuration.h and Configuration_adv.h file versions.

Marlin/language.h

@@ -137,7 +137,7 @@
 #define MSG_INVALID_EXTRUDER                "Invalid extruder"
 #define MSG_INVALID_SOLENOID                "Invalid solenoid"
 #define MSG_ERR_NO_THERMISTORS              "No thermistors - no temperature"
-#define MSG_M115_REPORT                     "FIRMWARE_NAME:Marlin " DETAILED_BUILD_VERSION " SOURCE_CODE_URL:" SOURCE_CODE_URL " PROTOCOL_VERSION:" PROTOCOL_VERSION " MACHINE_TYPE:" MACHINE_NAME " EXTRUDER_COUNT:" STRINGIFY(EXTRUDERS) " UUID:" MACHINE_UUID " MARLIN-AI3M_VERSION:" CUSTOM_BUILD_VERSION
+#define MSG_M115_REPORT                     "FIRMWARE_NAME:Marlin " DETAILED_BUILD_VERSION " MARLIN-AI3M_VERSION:" CUSTOM_BUILD_VERSION " SOURCE_CODE_URL:" SOURCE_CODE_URL " PROTOCOL_VERSION:" PROTOCOL_VERSION " MACHINE_TYPE:" MACHINE_NAME " EXTRUDER_COUNT:" STRINGIFY(EXTRUDERS) " UUID:" MACHINE_UUID
 #define MSG_MARLIN_AI3M                     "Marlin-AI3M"
 #define MSG_COUNT_X                         " Count X:"
 #define MSG_COUNT_A                         " Count A:"

README.md

@@ -9,12 +9,7 @@ Feel free to discuss issues and work with me further optimizing this firmware!
 I am running this version on an i3 Mega Ultrabase V3 (for distinction of the different versions, check [this Thingiverse thread](https://www.thingiverse.com/groups/anycubic-i3-mega/forums/general/topic:27064)).
 Basically, this should work on every Ultrabase version that has two Z-axis endstops.
 
-The new **Mega-S** should work too, but you will need to enter those two commands to make the new extruder work:
+The new **Mega-S** should work too, but you will need to enter two additional commands after flashing the firmware, mentioned in the instructions below.
-```
-M92 E384
-M500
-```
-Afterwards, calibration is highly recommended as per the instructions on the [Wiki](https://github.com/davidramiro/Marlin-AI3M/wiki/Calibration/).
 
 Looking for a **BLtouch firmware**? Head [this way](https://github.com/MNieddu91/Marlin-AI3M-BLTouch)! Mounting and configuration instructions are included.
 
@@ -26,7 +21,7 @@ A German translation of the instructions can be found [here](https://kore.cc/i3m
 
 ## Known issues:
 
-- **Cura users: Please turn off jerk and acceleration control in your print settings (not visible by default, select advanced visibility to unlock them). Cura's high default jerk and acceleration might cause shifted layers if you use TMC2208.**
+- Power outage support is not included
 - Estimated print times from your slicer might be slightly off.
 - Special characters on any file or folders name on the SD card will cause the file menu to freeze. Simply replace or remove every special character (Chinese, Arabic, Russian, accents, German & Scandinavian umlauts, ...) from the name. Symbols like dashes or underscores are no problem.
 **Important note: On the SD card that comes with the printer there is a folder with Chinese characters in it by default. Please rename or remove it.**
@@ -78,6 +73,11 @@ I provided three different precompiled hex files: One for no modifications on th
 - `M502` - load hard coded default values
 - `M500` - save them to EEPROM
 
+**If you are using this on a Mega-S, those two additional commands are necessary:**
+- `M92 E384` - set correct steps for the new extruder
+- `M500` - save them
+- I highly recommend calibrating the extruder.
+
 #### Calibration and other instructions have been moved to the [Wiki](https://github.com/davidramiro/Marlin-AI3M/wiki/Calibration).
 
 
@@ -182,6 +182,9 @@ G26 C H200 P25 R25
   - Place `M600` in your GCode at the desired layer or send it via terminal
   - Alternatively: Use `FilamentChange Pause` in the Special Menu
 - The nozzle will park and your printer will beep
+  - For safety reasons, the printer will turn off the hotend after 10 minutes. If you see the temperature being under the target:
+    - SD printing: Click `CONTINUE` **(only once!)** on the screen and wait for the hotend to heat up again.
+    - USB printing: Send `M108` and wait for the hotend to heat up again.
 - Remove the filament from the bowden tube
 - Insert the new filament right up to the nozzle, just until a bit of plastic oozes out
 - Remove the excess filament from the nozzle with tweezers
@@ -199,6 +202,9 @@ G26 C H200 P25 R25
   - Alternatively: Use `FilamentChange Pause` in the Special Menu
 - The nozzle will park
 - The printer will remove the filament right up to the extruder and beep when finished
+  - For safety reasons, the printer will turn off the hotend after 10 minutes. If you see the temperature being under the target:
+    - SD printing: Click `CONTINUE` **(only once!)** on the screen and wait for the hotend to heat up again.
+    - USB printing: Send `M108` and wait for the hotend to heat up again.
 - Insert the new filament just up to the end of the bowden fitting, as shown here:
 
 ![Load Filament][m600 load]