Eject filament feature in menu, M600: if it was envoked by FINDA, eject filament

Firmware/Marlin_main.cpp

@@ -3120,7 +3120,20 @@ void gcode_M600(bool automatic, float x_position, float y_position, float z_shif
 		}
 
 		if (mmu_enabled)
+		{
+			if (saved_printing) mmu_eject_filament(mmu_extruder, false); //if M600 was invoked by filament senzor (FINDA) eject filament so user can easily remove it
+			if (!automatic) mmu_M600_wait_and_beep();
+			if (saved_printing) {
+
+				lcd_clear();
+				lcd_set_cursor(0, 2);
+				lcd_puts_P(_T(MSG_PLEASE_WAIT));
+
+				mmu_command(MMU_CMD_R0);
+				manage_response(false, false);
+			}
 			mmu_M600_load_filament(automatic);
+		}
 		else
 			M600_load_filament();
 

Firmware/mmu.cpp

@@ -22,7 +22,7 @@
 #define MMU_HWRESET
 #define MMU_RST_PIN 76
 
-#define MMU_REQUIRED_FW_BUILDNR 81
+#define MMU_REQUIRED_FW_BUILDNR 83
 
 bool mmu_enabled = false;
 
@@ -470,7 +470,6 @@ void mmu_M600_load_filament(bool automatic)
 		  bool yes = false;
 		  tmp_extruder = mmu_extruder;
 		  if (!automatic) {
-			  mmu_M600_wait_and_beep();
 #ifdef MMU_M600_SWITCH_EXTRUDER
 			  yes = lcd_show_fullscreen_message_yes_no_and_wait_P(_i("Do you want to switch extruder?"), false);
 			  if(yes) tmp_extruder = choose_extruder_menu();
@@ -790,6 +789,36 @@ void extr_adj_4()
 #endif
 }
 
+void mmu_eject_fil_0()
+{
+	mmu_eject_filament(0, true);
+}
+
+void mmu_eject_fil_1()
+{
+	mmu_eject_filament(1, true);
+}
+
+void mmu_eject_fil_2()
+{
+	mmu_eject_filament(2, true);
+}
+
+void mmu_eject_fil_3()
+{
+	mmu_eject_filament(3, true);
+}
+
+void mmu_eject_fil_4()
+{
+	mmu_eject_filament(4, true);
+}
+
+void mmu_eject_fil_5()
+{
+	mmu_eject_filament(5, true);
+}
+
 void load_all()
 {
 #ifndef SNMM
@@ -921,7 +950,21 @@ void mmu_show_warning()
 	kill(_i("Please update firmware in your MMU2. Waiting for reset."));
 }
 
-static void mmu_eject_filament(uint8_t filament)
+void mmu_eject_filament(uint8_t filament, bool recover)
 {
-	if (filament < 5) mmu_command(MMU_CMD_E0 + filament);
+	if (filament < 5) 
+	{
+		mmu_command(MMU_CMD_E0 + filament);
+		manage_response(false, false);
+		if (recover)
+		{
+			lcd_show_fullscreen_message_and_wait_P(_i("Please remove filament and then press the knob."));
+			mmu_command(MMU_CMD_R0);
+			manage_response(false, false);
+		}
+	}
+	else
+	{
+		puts_P(PSTR("Filament nr out of range!"));
+	}
 }

Firmware/mmu.h

@@ -91,4 +91,9 @@ extern void extr_unload_4();
 
 extern bool mmu_check_version();
 extern void mmu_show_warning();
-
+extern void mmu_eject_filament(uint8_t filament, bool recover);
+extern void mmu_eject_fil_0();
+extern void mmu_eject_fil_1();
+extern void mmu_eject_fil_2();
+extern void mmu_eject_fil_3();
+extern void mmu_eject_fil_4();

Firmware/ultralcd.cpp

@@ -5203,6 +5203,19 @@ static void fil_load_menu()
 	MENU_END();
 }
 
+static void mmu_fil_eject_menu()
+{
+	MENU_BEGIN();
+	MENU_ITEM_BACK_P(_T(MSG_MAIN));
+	MENU_ITEM_FUNCTION_P(_i("Eject filament 1"), mmu_eject_fil_0);
+	MENU_ITEM_FUNCTION_P(_i("Eject filament 2"), mmu_eject_fil_1);
+	MENU_ITEM_FUNCTION_P(_i("Eject filament 3"), mmu_eject_fil_2);
+	MENU_ITEM_FUNCTION_P(_i("Eject filament 4"), mmu_eject_fil_3);
+	MENU_ITEM_FUNCTION_P(_i("Eject filament 5"), mmu_eject_fil_4);
+
+	MENU_END();
+}
+
 static void fil_unload_menu()
 {
 	MENU_BEGIN();
@@ -5651,6 +5664,7 @@ static void lcd_main_menu()
 	if (mmu_enabled)
 	{
 		MENU_ITEM_SUBMENU_P(_T(MSG_LOAD_FILAMENT), fil_load_menu);
+		MENU_ITEM_SUBMENU_P(_i("Eject filament"), mmu_fil_eject_menu);
 		if (mmu_enabled)
 			MENU_ITEM_GCODE_P(_T(MSG_UNLOAD_FILAMENT), PSTR("M702 C"));
 		else