Merge pull request #1369 from PavelSindler/M220_MK3

M220: possibility to backup/restore speed

Firmware/Marlin_main.cpp

@@ -394,6 +394,8 @@ static bool saved_extruder_relative_mode = false;
 static int saved_fanSpeed = 0; //!< Print fan speed
 //! @}
 
+static int saved_feedmultiply_mm = 100;
+
 //===========================================================================
 //=============================Routines======================================
 //===========================================================================
@@ -6078,12 +6080,20 @@ Sigma_Exit:
       SERIAL_ECHOLN("");
     }break;
     #endif
+
     case 220: // M220 S<factor in percent>- set speed factor override percentage
     {
-      if(code_seen('S'))
+      if (code_seen('B')) //backup current speed factor
       {
+        saved_feedmultiply_mm = feedmultiply;
+      }
+      if(code_seen('S'))
+      {		
         feedmultiply = code_value() ;
       }
+      if (code_seen('R')) { //restore previous feedmultiply
+        feedmultiply = saved_feedmultiply_mm;
+      }
     }
     break;
     case 221: // M221 S<factor in percent>- set extrude factor override percentage