Merge pull request MarlinFirmware#4111 from gudnimg/E-cool-gudni

Fix clicking noise during Toolchange when E-cool mode is enabled

Firmware/mmu2.cpp

@@ -922,10 +922,12 @@ void MMU2::ReportError(ErrorCode ec, ErrorSource res) {
     switch (logic.Progress()) {
     case ProgressCode::UnloadingToFinda:
         unloadFilamentStarted = false;
+        planner_abort_queued_moves();  // Abort excess E-moves to be safe
         break;
     case ProgressCode::FeedingToFSensor:
         // FSENSOR error during load. Make sure E-motor stops moving.
         loadFilamentStarted = false;
+        planner_abort_queued_moves(); // Abort excess E-moves to be safe
         break;
     default:
         break;
@@ -1040,6 +1042,10 @@ void MMU2::OnMMUProgressMsgSame(ProgressCode pc) {
             case FilamentState::AT_FSENSOR:
                 // fsensor triggered, finish FeedingToExtruder state
                 loadFilamentStarted = false;
+
+                // Abort any excess E-move from the planner queue
+                planner_abort_queued_moves();
+
                 // After the MMU knows the FSENSOR is triggered it will:
                 // 1. Push the filament by additional 30mm (see fsensorToNozzle)
                 // 2. Disengage the idler and push another 2mm.
@@ -1048,7 +1054,12 @@ void MMU2::OnMMUProgressMsgSame(ProgressCode pc) {
             case FilamentState::NOT_PRESENT:
                 // fsensor not triggered, continue moving extruder
                 if (!planner_any_moves()) { // Only plan a move if there is no move ongoing
-                    MoveE(2.0f, MMU2_LOAD_TO_NOZZLE_FEED_RATE);
+                    // Plan a very long move, where 'very long' is hundreds
+                    // of millimeters. Keep in mind though the move can't be much longer
+                    // than 450mm because the firmware will ignore too long extrusions
+                    // for safety reasons. See PREVENT_LENGTHY_EXTRUDE.
+                    // Use 350mm to be safely away from the prevention threshold
+                    MoveE(350.0f, MMU2_LOAD_TO_NOZZLE_FEED_RATE);
                 }
                 break;
             default:

Firmware/mmu2_marlin.h

@@ -26,6 +26,7 @@ void MoveE(float delta, float feedRate);
 
 float MoveRaiseZ(float delta);
 
+void planner_abort_queued_moves();
 void planner_synchronize();
 bool planner_any_moves();
 float planner_get_machine_position_E_mm();

Firmware/mmu2_marlin1.cpp

@@ -18,6 +18,17 @@ float MoveRaiseZ(float delta) {
     return raise_z(delta);
 }
 
+void planner_abort_queued_moves() {
+    planner_abort_hard();
+
+    // Unblock the planner. This should be safe in the
+    // toolchange context. Currently we are mainly aborting
+    // excess E-moves after detecting filament during toolchange.
+    // If a MMU error is reported, the planner must be unblocked
+    // as well so the extruder can be parked safely.
+    planner_aborted = false;
+}
+
 void planner_synchronize() {
     st_synchronize();
 }