Added new G-Code: M78

Marlin/Marlin.h

 
 #include "WString.h"
 
-#include "stopwatch.h"
+#if ENABLED(PRINTCOUNTER)
+  #include "printcounter.h"
+#else
+  #include "stopwatch.h"
+#endif
 
 #ifdef USBCON
   #if ENABLED(BLUETOOTH)
 #endif
 
 // Print job timer
-extern Stopwatch print_job_timer;
+#if ENABLED(PRINTCOUNTER)
+  extern PrintCounter print_job_timer;
+#else
+  extern Stopwatch print_job_timer;
+#endif
 
 // Handling multiple extruders pins
 extern uint8_t active_extruder;

Marlin/Marlin_main.cpp

 static millis_t stepper_inactive_time = (DEFAULT_STEPPER_DEACTIVE_TIME) * 1000UL;
 
 // Print Job Timer
-Stopwatch print_job_timer = Stopwatch();
+#if ENABLED(PRINTCOUNTER)
+  PrintCounter print_job_timer = PrintCounter();
+#else
+  Stopwatch print_job_timer = Stopwatch();
+#endif
 
 static uint8_t target_extruder;
 
   print_job_timer.stop();
 }
 
+#if ENABLED(PRINTCOUNTER)
+  /*+
+   * M78: Show print statistics
+   */
+  inline void gcode_M78() {
+    print_job_timer.showStats();
+  }
+#endif
+
 /**
  * M104: Set hot end temperature
  */
         gcode_M77();
         break;
 
+      #if ENABLED(PRINTCOUNTER)
+        case 78: // Show print statistics
+          gcode_M78();
+          break;
+      #endif
+
       #if ENABLED(M100_FREE_MEMORY_WATCHER)
         case 100:
           gcode_M100();
   );
   host_keepalive();
   lcd_update();
+  #if ENABLED(PRINTCOUNTER)
+      print_job_timer.tick();
+  #endif
 }
 
 /**