Allow load filament retry after button push unlimited times in case mmu_continue_loading() is in blocking mode.

Firmware/mmu.cpp

@@ -1466,74 +1466,109 @@ static void load_more()
     st_synchronize();
 }
 
+static void increment_load_fail()
+{
+    uint8_t mmu_load_fail = eeprom_read_byte((uint8_t*)EEPROM_MMU_LOAD_FAIL);
+    uint16_t mmu_load_fail_tot = eeprom_read_word((uint16_t*)EEPROM_MMU_LOAD_FAIL_TOT);
+    if(mmu_load_fail < 255) eeprom_update_byte((uint8_t*)EEPROM_MMU_LOAD_FAIL, mmu_load_fail + 1);
+    if(mmu_load_fail_tot < 65535) eeprom_update_word((uint16_t*)EEPROM_MMU_LOAD_FAIL_TOT, mmu_load_fail_tot + 1);
+}
+
+//! @brief continue loading filament
 //! @par blocking
-//!  * true blocking
-//!  * false non-blocking
+//!  * true blocking - do not return until successful load
+//!  * false non-blocking - pause print and return on load failure
+//!
+//! @startuml
+//! [*] --> [*] : !ir_sensor_detected /\n send MmuCmd::C0
+//! [*] --> LoadMore
+//! LoadMore --> [*] : filament \ndetected
+//! LoadMore --> Retry : !filament detected /\n increment load fail
+//! Retry --> [*] : filament \ndetected
+//! Retry --> Unload : !filament \ndetected
+//! Unload --> [*] : non-blocking
+//! Unload --> Retry : button \nclicked
+//!
+//! Retry : Cut filament if enabled
+//! Retry : repeat last T-code
+//! Unload : unload filament
+//! Unload : pause print
+//! Unload : show error message
+//!
+//! @enduml
 void mmu_continue_loading(bool blocking)
 {
-	if (ir_sensor_detected)
+	if (!ir_sensor_detected)
 	{
-	    load_more();
+	    mmu_command(MmuCmd::C0);
+	    return;
+	}
 
-		if (PIN_GET(IR_SENSOR_PIN) != 0) {
-			uint8_t mmu_load_fail = eeprom_read_byte((uint8_t*)EEPROM_MMU_LOAD_FAIL);
-			uint16_t mmu_load_fail_tot = eeprom_read_word((uint16_t*)EEPROM_MMU_LOAD_FAIL_TOT);
-			if(mmu_load_fail < 255) eeprom_update_byte((uint8_t*)EEPROM_MMU_LOAD_FAIL, mmu_load_fail + 1);
-			if(mmu_load_fail_tot < 65535) eeprom_update_word((uint16_t*)EEPROM_MMU_LOAD_FAIL_TOT, mmu_load_fail_tot + 1);
+    load_more();
 
+    enum class Ls : uint_least8_t
+    {
+        enter,
+        retry,
+        unload,
+    };
+    Ls state = Ls::enter;
+
+    while (PIN_GET(IR_SENSOR_PIN) != 0)
+    {
+        switch (state)
+        {
+        case Ls::enter:
+            increment_load_fail();
+            // no break
+        case Ls::retry:
 #ifdef MMU_HAS_CUTTER
-			if (1 == eeprom_read_byte((uint8_t*)EEPROM_MMU_CUTTER_ENABLED))
-			{
-			    mmu_command(MmuCmd::K0 + tmp_extruder);
-			    manage_response(true, true, MMU_UNLOAD_MOVE);
-			}
+            if (1 == eeprom_read_byte((uint8_t*)EEPROM_MMU_CUTTER_ENABLED))
+            {
+                mmu_command(MmuCmd::K0 + tmp_extruder);
+                manage_response(true, true, MMU_UNLOAD_MOVE);
+            }
 #endif //MMU_HAS_CUTTER
-
             mmu_command(MmuCmd::T0 + tmp_extruder);
             manage_response(true, true, MMU_TCODE_MOVE);
             load_more();
-
-            if (PIN_GET(IR_SENSOR_PIN) != 0)
+            state = Ls::unload;
+            break;
+        case Ls::unload:
+            stop_and_save_print_to_ram(0, 0);
+
+            //lift z
+            current_position[Z_AXIS] += Z_PAUSE_LIFT;
+            if (current_position[Z_AXIS] > Z_MAX_POS) current_position[Z_AXIS] = Z_MAX_POS;
+            plan_buffer_line(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS], 15, active_extruder);
+            st_synchronize();
+
+            //Move XY to side
+            current_position[X_AXIS] = X_PAUSE_POS;
+            current_position[Y_AXIS] = Y_PAUSE_POS;
+            plan_buffer_line(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS], 50, active_extruder);
+            st_synchronize();
+
+            mmu_command(MmuCmd::U0);
+            manage_response(false, true, MMU_UNLOAD_MOVE);
+
+            setAllTargetHotends(0);
+            lcd_setstatuspgm(_i("MMU load failed     "));////c=20 r=1
+
+            if (blocking)
             {
-                //pause print, show error message and then repeat last T-code
-                stop_and_save_print_to_ram(0, 0);
-
-                //lift z
-                current_position[Z_AXIS] += Z_PAUSE_LIFT;
-                if (current_position[Z_AXIS] > Z_MAX_POS) current_position[Z_AXIS] = Z_MAX_POS;
-                plan_buffer_line(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS], 15, active_extruder);
-                st_synchronize();
-
-                //Move XY to side
-                current_position[X_AXIS] = X_PAUSE_POS;
-                current_position[Y_AXIS] = Y_PAUSE_POS;
-                plan_buffer_line(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS], 50, active_extruder);
-                st_synchronize();
-
-                mmu_command(MmuCmd::U0);
-                manage_response(false, true, MMU_UNLOAD_MOVE);
-
-                setAllTargetHotends(0);
-                lcd_setstatuspgm(_i("MMU load failed     "));////MSG_RECOVERING_PRINT c=20 r=1
-
-                if (blocking)
-                {
-                    marlin_wait_for_click();
-                    restore_print_from_ram_and_continue(0);
-                    mmu_command(MmuCmd::T0 + tmp_extruder);
-                    manage_response(true, true, MMU_TCODE_MOVE);
-                    load_more();
-                }
-                else
-                {
-                    mmu_fil_loaded = false; //so we can retry same T-code again
-                    isPrintPaused = true;
-                    mmu_command(MmuCmd::W0);
-                }
+                marlin_wait_for_click();
+                restore_print_from_ram_and_continue(0);
+                state = Ls::retry;
             }
-		}
-	}
-	else { //mmu_ir_sensor_detected == false
-		mmu_command(MmuCmd::C0);
-	}
+            else
+            {
+                mmu_fil_loaded = false; //so we can retry same T-code again
+                isPrintPaused = true;
+                mmu_command(MmuCmd::W0);
+                return;
+            }
+            break;
+        }
+    }
 }

Firmware/mmu.h

@@ -58,7 +58,7 @@ enum class MmuCmd : uint_least8_t
     K4,
     R0,
     S3,
-    W0,
+    W0, //!< Wait and signal load error
 };
 
 inline MmuCmd operator+ (MmuCmd cmd, uint8_t filament)