Change undocumented behaviour of M190 (Wait for bed temperature). Document M190 and M109 (Wait for extruder temperature).

Do not remember CooldownNoWait property set by M190 and M109. If M190 was invoked without parameters, CooldownNoWait property was set if it was previously set by "M109 S" or "M109 S" or printer was after power up. Otherwise CooldownNoWait was not set. Now CooldownNoWait is never set if M190 is invoked without parameters.

Saves 44 B of FLASH memory.

Firmware/Marlin_main.cpp

@@ -365,7 +365,6 @@ bool Stopped=false;
   Servo servos[NUM_SERVOS];
 #endif
 
-bool CooldownNoWait = true;
 bool target_direction;
 
 //Insert variables if CHDK is defined
@@ -6006,6 +6005,14 @@ Sigma_Exit:
     }
 
     //! ### M109 - Wait for extruder temperature
+    //! Parameters (not mandatory):
+    //! * S \<temp\> set extruder temperature
+    //! * R \<temp\> set extruder temperature
+    //!
+    //! Parameters S and R are treated identically.
+    //! Command always waits for both cool down and heat up.
+    //! If no parameters are supplied waits for previously
+    //! set extruder temperature.
     // -------------------------------------------------
     case 109:
     {
@@ -6022,10 +6029,8 @@ Sigma_Exit:
       #endif
       if (code_seen('S')) {
           setTargetHotendSafe(code_value(), extruder);
-              CooldownNoWait = true;
             } else if (code_seen('R')) {
                 setTargetHotendSafe(code_value(), extruder);
-        CooldownNoWait = false;
       }
       #ifdef AUTOTEMP
         if (code_seen('S')) autotemp_min=code_value();
@@ -6060,9 +6065,15 @@ Sigma_Exit:
       break;
 
     //! ### M190 - Wait for bed temperature
-    // ---------------------------------------
+    //! Parameters (not mandatory):
+    //! * S \<temp\> set extruder temperature and wait for heating
+    //! * R \<temp\> set extruder temperature and wait for heating or cooling
+    //!
+    //! If no parameter is supplied, waits for heating or cooling to previously set temperature.
     case 190: 
     #if defined(TEMP_BED_PIN) && TEMP_BED_PIN > -1
+    {
+        bool CooldownNoWait = false;
         LCD_MESSAGERPGM(_T(MSG_BED_HEATING));
 		heating_status = 3;
 		if (farm_mode) { prusa_statistics(1); };
@@ -6074,7 +6085,6 @@ Sigma_Exit:
 		else if (code_seen('R')) 
 		{
           setTargetBed(code_value());
-          CooldownNoWait = false;
         }
         codenum = _millis();
         
@@ -6108,6 +6118,7 @@ Sigma_Exit:
 		heating_status = 4;
 
         previous_millis_cmd = _millis();
+    }
     #endif
         break;