Merge remote-tracking branch 'upstream/Marlin_v1' into Marlin_v1

Marlin/temperature.cpp

@@ -326,10 +326,10 @@ void manage_heater()
     #ifndef PID_OPENLOOP
         pid_error[e] = target_temperature[e] - pid_input;
         if(pid_error[e] > PID_FUNCTIONAL_RANGE) {
-          pid_output = PID_MAX;
+          pid_output = BANG_MAX;
           pid_reset[e] = true;
         }
-        else if(pid_error[e] < -PID_FUNCTIONAL_RANGE) {
+        else if(pid_error[e] < -PID_FUNCTIONAL_RANGE || target_temperature[e] == 0) {
           pid_output = 0;
           pid_reset[e] = true;
         }
@@ -1177,3 +1177,31 @@ ISR(TIMER0_COMPB_vect)
 #endif
   }  
 }
+
+#ifdef PIDTEMP
+// Apply the scale factors to the PID values
+
+
+float scalePID_i(float i)
+{
+	return i*PID_dT;
+}
+
+float unscalePID_i(float i)
+{
+	return i/PID_dT;
+}
+
+float scalePID_d(float d)
+{
+    return d/PID_dT;
+}
+
+float unscalePID_d(float d)
+{
+	return d*PID_dT;
+}
+
+#endif //PIDTEMP
+
+