Implement Push/Pull V-Tool, Report All Mixes via M165 R, and full E support

Marlin/Configuration.h

@@ -351,12 +351,17 @@
 #if ENABLED(MIXING_EXTRUDER)
   #define MIXING_STEPPERS 2        // Number of steppers in your mixing extruder
   #define MIXING_VIRTUAL_TOOLS 16  // Use the Virtual Tool method with M163 and M164
-  //#define DIRECT_MIXING_IN_G1    // Allow ABCDHI mix factors in G1 movement commands
+  //#define DIRECT_MIXING_IN_G1    // Allow ABCDLMNO mix factors in G1 movement commands, and R for reporting all V-tool mixes
   //#define GRADIENT_MIX           // Support for gradient mixing with M166 and LCD
   //#define MIXING_PRESETS         // Assign 8 default V-tool presets for 2 or 3 MIXING_STEPPERS
+  //#define PUSH_PULL_TOOLCHANGE   // Simultaneously push the new V-tool and pull the old V-tool into the melt chamber
   #if ENABLED(GRADIENT_MIX)
     //#define GRADIENT_VTOOL       // Add M166 T to use a V-tool index as a Gradient alias
   #endif
+  #if ENABLED(PUSH_PULL_TOOLCHANGE)
+    #define MIXING_PUSH_PULL_MM         3    // (mm)     Maximum length for a single extruder to push/pull
+    #define MIXING_PUSH_PULL_FEEDRATE   300  // (mm/min) V-tool extruder feedrate
+  #endif
 #endif
 
 // Offset of the extruders (uncomment if using more than one and relying on firmware to position when changing).

Marlin/src/core/language.h

@@ -188,6 +188,7 @@
 #define STR_ERR_COLD_EXTRUDE_STOP           " cold extrusion prevented"
 #define STR_ERR_LONG_EXTRUDE_STOP           " too long extrusion prevented"
 #define STR_ERR_HOTEND_TOO_COLD             "Hotend too cold"
+#define STR_ERR_PUSHPULL_TOO_COLD           "V-tool switched without push/pull"
 #define STR_ERR_EEPROM_WRITE                "Error writing to EEPROM!"
 #define STR_ERR_EEPROM_CORRUPT              "EEPROM Corrupt"
 
@@ -321,6 +322,7 @@
 #define STR_TEMPERATURE_UNITS               "Temperature Units"
 #define STR_USER_THERMISTORS                "User thermistors"
 #define STR_DELAYED_POWEROFF                "Delayed poweroff"
+#define STR_CURRENT_VTOOLS                  "Current virtual tool mixes"
 
 //
 // Endstop Names used by Endstops::report_states

Marlin/src/feature/mixing.cpp

@@ -42,7 +42,7 @@ int_fast8_t   Mixer::runner = 0;
 mixer_comp_t  Mixer::s_color[MIXING_STEPPERS];
 mixer_accu_t  Mixer::accu[MIXING_STEPPERS] = { 0 };
 
-#if ANY(HAS_DUAL_MIXING, GRADIENT_MIX)
+#if ANY(HAS_DUAL_MIXING, GRADIENT_MIX, PUSH_PULL_TOOLCHANGE)
   mixer_perc_t Mixer::mix[MIXING_STEPPERS];
 #endif
 
@@ -154,6 +154,13 @@ void Mixer::refresh_collector(const float proportion/*=1.0*/, const uint8_t t/*=
   //SERIAL_EOL();
 }
 
+#if ENABLED(PUSH_PULL_TOOLCHANGE)
+  pushpull_t Mixer::pushpull = {
+    0,  // e_directions
+    0,  // scale
+  };
+#endif
+
 #if ENABLED(GRADIENT_MIX)
 
   #include "../module/motion.h"

Marlin/src/feature/mixing.h

@@ -51,12 +51,16 @@ enum MixTool {
   #if HAS_MIXER_SYNC_CHANNEL
     , MIXER_AUTORETRACT_TOOL
   #endif
+  #if ENABLED(PUSH_PULL_TOOLCHANGE)
+    , MIXER_PUSHPULL_TOOL
+  #endif
   , NR_MIXING_VIRTUAL_TOOLS
 };
 
-#define MAX_VTOOLS TERN(HAS_MIXER_SYNC_CHANNEL, 254, 255)
+#define MAX_VTOOLS  (255 TERN_(PUSH_PULL_TOOLCHANGE, -1) TERN_(HAS_MIXER_SYNC_CHANNEL, -1))
 static_assert(NR_MIXING_VIRTUAL_TOOLS <= MAX_VTOOLS, "MIXING_VIRTUAL_TOOLS must be <= " STRINGIFY(MAX_VTOOLS) "!");
 
+#define VTOOLS_LOOP(VAR) for (uint_fast8_t VAR = 0; VAR < MIXING_VIRTUAL_TOOLS; VAR++)
 #define MIXER_STEPPER_LOOP(VAR) for (uint_fast8_t VAR = 0; VAR < MIXING_STEPPERS; VAR++)
 
 #if ENABLED(GRADIENT_MIX)
@@ -75,6 +79,13 @@ static_assert(NR_MIXING_VIRTUAL_TOOLS <= MAX_VTOOLS, "MIXING_VIRTUAL_TOOLS must
 
 #endif
 
+#if ENABLED(PUSH_PULL_TOOLCHANGE)
+  typedef struct {
+    uint8_t direction_bits;                   // Extruder direction, where 1 is negative
+    float scale;                              // The scale to multiply the extruder speed and length
+  } pushpull_t;
+#endif
+
 /**
  * @brief Mixer class
  * @details Contains data and behaviors for a Mixing Extruder
@@ -118,24 +129,24 @@ class Mixer {
     MIXER_STEPPER_LOOP(i) s_color[i] = b_color[i];
   }
 
-  #if ANY(HAS_DUAL_MIXING, GRADIENT_MIX)
+  #if ANY(PUSH_PULL_TOOLCHANGE, HAS_DUAL_MIXING, GRADIENT_MIX)
 
     static mixer_perc_t mix[MIXING_STEPPERS];  // Scratch array for the Mix in proportion to 100
 
     static void copy_mix_to_color(mixer_comp_t (&tcolor)[MIXING_STEPPERS]) {
       // Scale each component to the largest one in terms of COLOR_A_MASK
       // So the largest component will be COLOR_A_MASK and the other will be in proportion to it
       const float scale = (COLOR_A_MASK) * RECIPROCAL(_MAX(
-        LIST_N(MIXING_STEPPERS, mix[0], mix[1], mix[2], mix[3], mix[4], mix[5])
+        LIST_N(MIXING_STEPPERS, mix[0], mix[1], mix[2], mix[3], mix[4], mix[5], mix[6], mix[7])
       ));
 
       // Scale all values so their maximum is COLOR_A_MASK
       MIXER_STEPPER_LOOP(i) tcolor[i] = mix[i] * scale;
 
       #ifdef MIXER_NORMALIZER_DEBUG
         SERIAL_ECHOLN(
-          F("Mix [ "), LIST_N(MIXING_STEPPERS, mix[0], mix[1], mix[2], mix[3], mix[4], mix[5]),
-          F(" ] to Color [ "), LIST_N(MIXING_STEPPERS, tcolor[0], tcolor[1], tcolor[2], tcolor[3], tcolor[4], tcolor[5]),
+          F("Mix [ "), LIST_N(MIXING_STEPPERS, mix[0], mix[1], mix[2], mix[3], mix[4], mix[5], mix[6], mix[7]),
+          F(" ] to Color [ "), LIST_N(MIXING_STEPPERS, tcolor[0], tcolor[1], tcolor[2], tcolor[3], tcolor[4], tcolor[5], tcolor[6], tcolor[7]),
           F(" ]")
         );
       #endif
@@ -148,13 +159,43 @@ class Mixer {
 
       #ifdef MIXER_NORMALIZER_DEBUG
         SERIAL_ECHOLN(F("V-tool "), j,
-          F(" [ "), LIST_N(MIXING_STEPPERS, color[j][0], color[j][1], color[j][2], color[j][3], color[j][4], color[j][5]),
-          F(" ] to Mix [ "), LIST_N(MIXING_STEPPERS, mix[0], mix[1], mix[2], mix[3], mix[4], mix[5]), F(" ]")
+          F(" [ "), LIST_N(MIXING_STEPPERS, color[j][0], color[j][1], color[j][2], color[j][3], color[j][4], color[j][5], color[j][6], color[j][7]),
+          F(" ] to Mix [ "), LIST_N(MIXING_STEPPERS, mix[0], mix[1], mix[2], mix[3], mix[4], mix[5], mix[6], mix[7]), F(" ]")
         );
       #endif
     }
 
-  #endif // HAS_DUAL_MIXING || GRADIENT_MIX
+  #endif // PUSH_PULL_TOOLCHANGE || HAS_DUAL_MIXING || GRADIENT_MIX
+
+  #if ENABLED(PUSH_PULL_TOOLCHANGE)
+    static pushpull_t pushpull;
+
+    // Outputs true for positive direction. Used in Stepper.
+    FORCE_INLINE static bool e_dir(uint_fast8_t VAR) { return !TEST(pushpull.direction_bits, VAR); }
+
+    // Update the push/pull v-tool, its direction bits and scale factor
+    static void update_pushpull_tool(const uint_fast8_t new_vtool){
+      pushpull.direction_bits = 0; pushpull.scale = 0;
+      if (new_vtool == selected_vtool) return;
+
+      mixer_perc_t pull_mix[MIXING_STEPPERS] = {0};
+      update_mix_from_vtool();
+      MIXER_STEPPER_LOOP(i) pull_mix[i] = mix[i];
+      update_mix_from_vtool(new_vtool);
+      MIXER_STEPPER_LOOP(i) {
+        mix[i] -= pull_mix[i];
+        if (mix[i] < 0) {
+          SBI(pushpull.direction_bits, i);
+          mix[i] *= -1.0f;
+        }
+      }
+      copy_mix_to_color(color[MIXER_PUSHPULL_TOOL]);
+
+      float ctot = 0;
+      MIXER_STEPPER_LOOP(i) ctot += color[MIXER_PUSHPULL_TOOL][i];
+      pushpull.scale = ctot / (COLOR_A_MASK);
+    }
+  #endif // PUSH_PULL_TOOLCHANGE
 
   #if HAS_DUAL_MIXING
 
@@ -192,8 +233,9 @@ class Mixer {
 
       #ifdef MIXER_NORMALIZER_DEBUG
         SERIAL_ECHOLN(
-          F("Gradient [ "), LIST_N(MIXING_STEPPERS, gradient.color[0], gradient.color[1], gradient.color[2], gradient.color[3], gradient.color[4], gradient.color[5]),
-          F(" ] to Mix [ "), LIST_N(MIXING_STEPPERS, mix[0], mix[1], mix[2], mix[3], mix[4], mix[5]), F(" ]")
+          F("Gradient [ "), LIST_N(MIXING_STEPPERS, gradient.color[0], gradient.color[1], gradient.color[2], gradient.color[3], 
+            gradient.color[4], gradient.color[5], gradient.color[6], gradient.color[7]),
+          F(" ] to Mix [ "), LIST_N(MIXING_STEPPERS, mix[0], mix[1], mix[2], mix[3], mix[4], mix[5], mix[6], mix[7]), F(" ]")
         );
       #endif
     }

Marlin/src/gcode/feature/mixing/M163-M165.cpp

@@ -72,14 +72,16 @@ void GcodeSuite::M164() {
    *   B[factor] Mix factor for extruder stepper 2
    *   C[factor] Mix factor for extruder stepper 3
    *   D[factor] Mix factor for extruder stepper 4
-   *   H[factor] Mix factor for extruder stepper 5
-   *   I[factor] Mix factor for extruder stepper 6
+   *   L[factor] Mix factor for extruder stepper 5
+   *   M[factor] Mix factor for extruder stepper 6
+   *   N[factor] Mix factor for extruder stepper 7
+   *   O[factor] Mix factor for extruder stepper 8
    */
   void GcodeSuite::M165() {
     // Get mixing parameters from the G-Code
     // The total "must" be 1.0 (but it will be normalized)
     // If no mix factors are given, the old mix is preserved
-    const char mixing_codes[] = { LIST_N(MIXING_STEPPERS, 'A', 'B', 'C', 'D', 'H', 'I') };
+    const char mixing_codes[] = { LIST_N(MIXING_STEPPERS, 'A', 'B', 'C', 'D', 'L', 'M', 'N', 'O') };
     uint8_t mix_bits = 0;
     MIXER_STEPPER_LOOP(i) {
       if (parser.seenval(mixing_codes[i])) {
@@ -94,6 +96,27 @@ void GcodeSuite::M164() {
         if (!TEST(mix_bits, i)) mixer.set_collector(i, 0.0f);
       mixer.normalize();
     }
+    // Report the latest V-tool mixes
+    if (parser.seen_test('R')) M165_report();
+  }
+
+  void GcodeSuite::M165_report(const bool forReplay/*=true*/) {
+    gcode.report_heading_etc(forReplay, F(STR_CURRENT_VTOOLS));
+    VTOOLS_LOOP(i) {
+      // Get mixes from all tools as a percentage
+      mixer.refresh_collector(100.0, i);
+      SERIAL_ECHO(F("  V"), i, ":");  // Avoid using 'Tn:' substring so output is fully visible on
+                                      // BTT Touchscreen terminal.
+      SERIAL_ECHOLNPGM(LIST_N(DOUBLE(MIXING_STEPPERS),
+         "  A", p_float_t(mixer.collector[0], 1),
+          " B", p_float_t(mixer.collector[1], 1),
+          " C", p_float_t(mixer.collector[2], 1),
+          " D", p_float_t(mixer.collector[3], 1),
+          " L", p_float_t(mixer.collector[4], 1),
+          " M", p_float_t(mixer.collector[5], 1),
+          " N", p_float_t(mixer.collector[6], 1),
+          " O", p_float_t(mixer.collector[7], 1)));
+    }
   }
 
 #endif // DIRECT_MIXING_IN_G1

Marlin/src/gcode/gcode.cpp

@@ -210,7 +210,7 @@ void GcodeSuite::get_destination_from_command() {
       print_job_timer.incFilamentUsed(destination.e - current_position.e);
   #endif
 
-  // Get ABCDHI mixing factors
+  // Get ABCDLMNO mixing factors
   #if ALL(MIXING_EXTRUDER, DIRECT_MIXING_IN_G1)
     M165();
   #endif

Marlin/src/gcode/gcode.h

@@ -176,7 +176,7 @@
  * M155 - Auto-report temperatures with interval of S<seconds>. (Requires AUTO_REPORT_TEMPERATURES)
  * M163 - Set a single proportion for a mixing extruder. (Requires MIXING_EXTRUDER)
  * M164 - Commit the mix and save to a virtual tool (current, or as specified by 'S'). (Requires MIXING_EXTRUDER)
- * M165 - Set the mix for the mixing extruder (and current virtual tool) with parameters ABCDHI. (Requires MIXING_EXTRUDER and DIRECT_MIXING_IN_G1)
+ * M165 - Set the mix for the mixing extruder (and current virtual tool) with parameters ABCDLMNO. (Requires MIXING_EXTRUDER and DIRECT_MIXING_IN_G1)
  * M166 - Set the Gradient Mix for the mixing extruder. (Requires GRADIENT_MIX)
  * M190 - Set bed target temperature and wait. R<temp> Set target temperature and wait. S<temp> Set, but only wait when heating. (Requires TEMP_SENSOR_BED)
  * M192 - Wait for probe to reach target temperature. (Requires TEMP_SENSOR_PROBE)
@@ -848,6 +848,7 @@ class GcodeSuite {
     static void M164();
     #if ENABLED(DIRECT_MIXING_IN_G1)
       static void M165();
+      static void M165_report(const bool forReplay=true);
     #endif
     #if ENABLED(GRADIENT_MIX)
       static void M166();

Marlin/src/module/stepper.cpp

@@ -500,7 +500,11 @@ xyze_int8_t Stepper::count_direction{0};
 //#define E7_APPLY_DIR(FWD) do{ (FWD) ? FWD_E_DIR(7) : REV_E_DIR(7); }while(0)
 
 #if ENABLED(MIXING_EXTRUDER)
-  #define E_APPLY_DIR(FWD,Q) do{ if (FWD) { MIXER_STEPPER_LOOP(j) FWD_E_DIR(j); } else { MIXER_STEPPER_LOOP(j) REV_E_DIR(j); } }while(0)
+  #if ENABLED(PUSH_PULL_TOOLCHANGE)
+    #define E_APPLY_DIR(FWD,Q) MIXER_STEPPER_LOOP(j) do{ if (FWD == mixer.e_dir(j)) { FWD_E_DIR(j); } else { REV_E_DIR(j); } }while(0)
+  #else
+    #define E_APPLY_DIR(FWD,Q) do{ if (FWD) { MIXER_STEPPER_LOOP(j) FWD_E_DIR(j); } else { MIXER_STEPPER_LOOP(j) REV_E_DIR(j); } }while(0)
+  #endif
 #else
   #define E_APPLY_STEP(FWD,Q) E_STEP_WRITE(stepper_extruder, FWD)
   #define E_APPLY_DIR(FWD,Q) do{ if (FWD) { FWD_E_DIR(stepper_extruder); } else { REV_E_DIR(stepper_extruder); } }while(0)

Marlin/src/module/stepper/indirection.h

@@ -1062,7 +1062,7 @@ void reset_stepper_drivers();    // Called by settings.load / settings.reset
 #if ENABLED(MIXING_EXTRUDER)
 
   /**
-   * Mixing steppers keep all their enable (and direction) states synchronized
+   * Mixing steppers keep all their enable states synchronized
    */
   #define _CALL_ENA_E(N)  ENABLE_STEPPER_E##N () ;
   #define _CALL_DIS_E(N) DISABLE_STEPPER_E##N () ;

Marlin/src/module/tool_change.cpp

@@ -66,6 +66,9 @@
 
 #if ENABLED(MIXING_EXTRUDER)
   #include "../feature/mixing.h"
+  #if ENABLED(PUSH_PULL_TOOLCHANGE)
+    #include "stepper.h"
+  #endif
 #endif
 
 #if HAS_LEVELING
@@ -892,6 +895,22 @@ void fast_line_to_current(const AxisEnum fr_axis) { _line_to_current(fr_axis, 0.
 
 #endif // DUAL_X_CARRIAGE
 
+#if ANY(TOOLCHANGE_FILAMENT_SWAP, MIXING_EXTRUDER)
+  /**
+   * Check if too cold to move the specified tool
+   *
+   * Returns TRUE if too cold to move (also echos message: STR_ERR_HOTEND_TOO_COLD)
+   * Returns FALSE if able to move.
+   */
+  bool too_cold(uint8_t toolID){
+    if (!DEBUGGING(DRYRUN) && thermalManager.targetTooColdToExtrude(toolID)) {
+      SERIAL_ECHO_MSG(STR_ERR_HOTEND_TOO_COLD);
+      return true;
+    }
+    return false;
+  }
+#endif // TOOLCHANGE_FILAMENT_SWAP || MIXING_EXTRUDER
+
 /**
  * Prime active tool using TOOLCHANGE_FILAMENT_SWAP settings
  */
@@ -916,20 +935,6 @@ void fast_line_to_current(const AxisEnum fr_axis) { _line_to_current(fr_axis, 0.
     #endif
   }
 
-  /**
-   * Check if too cold to move the specified tool
-   *
-   * Returns TRUE if too cold to move (also echos message: STR_ERR_HOTEND_TOO_COLD)
-   * Returns FALSE if able to  move.
-   */
-  bool too_cold(uint8_t toolID){
-    if (!DEBUGGING(DRYRUN) && thermalManager.targetTooColdToExtrude(toolID)) {
-      SERIAL_ECHO_MSG(STR_ERR_HOTEND_TOO_COLD);
-      return true;
-    }
-    return false;
-  }
-
   /**
    * Cutting recovery -- Recover from cutting retraction that occurs at the end of nozzle priming
    *
@@ -1118,6 +1123,28 @@ void tool_change(const uint8_t new_tool, bool no_move/*=false*/) {
       return invalid_extruder_error(new_tool);
 
     #if MIXING_VIRTUAL_TOOLS > 1
+      #if ENABLED(PUSH_PULL_TOOLCHANGE)
+        if (too_cold(active_extruder)) SERIAL_ECHO_MSG(STR_ERR_PUSHPULL_TOO_COLD);
+        else {          
+          mixer.update_pushpull_tool(new_tool);
+
+          if (mixer.pushpull.scale > 0) {
+            // Enable Push/Pull V-Tool
+            stepper.apply_directions();
+            mixer.T(MIXER_PUSHPULL_TOOL);
+
+            // Extrude
+            float resume_current_e = current_position.e;
+            unscaled_e_move(MIXING_PUSH_PULL_MM * mixer.pushpull.scale, 
+                            MMM_TO_MMS(MIXING_PUSH_PULL_FEEDRATE) * mixer.pushpull.scale);
+
+            // Reset
+            mixer.pushpull.direction_bits = 0; stepper.apply_directions();
+            current_position.e = resume_current_e; sync_plan_position_e();
+          }
+        }
+      #endif 
+
       // T0-Tnnn: Switch virtual tool by changing the index to the mix
       mixer.T(new_tool);
     #endif