Update RelayOutput for minimum relay on time and consistent window behavior

jamesprior · jamesprior · commit 0aa6c0a88f9a · 2013-01-23T19:38:45.000-06:00
diff --git a/PID_v1/Examples/PID_RelayOutput/PID_RelayOutput.ino b/PID_v1/Examples/PID_RelayOutput/PID_RelayOutput.ino
@@ -24,6 +24,7 @@ double Setpoint, Input, Output;
 PID myPID(&Input, &Output, &Setpoint,2,5,1, DIRECT);
 
 int WindowSize = 5000;
+int minWindow = 500;
 unsigned long windowStartTime;
 void setup()
 {
@@ -42,16 +43,16 @@ void setup()
 void loop()
 {
   Input = analogRead(0);
-  myPID.Compute();
 
   /************************************************
    * turn the output pin on/off based on pid output
    ************************************************/
   if(millis() - windowStartTime>WindowSize)
-  { //time to shift the Relay Window
+  { //time to shift the Relay Window and recalculate
     windowStartTime += WindowSize;
+    myPID.Compute();
   }
-  if(Output < millis() - windowStartTime) digitalWrite(RelayPin,HIGH);
+  if(Output > minWindow && Output < millis() - windowStartTime) digitalWrite(RelayPin,HIGH);
   else digitalWrite(RelayPin,LOW);
 
 }

Original file line number	Diff line number	Diff line change
`@@ -24,6 +24,7 @@ double Setpoint, Input, Output;`
`24`	`24`	`PID myPID(&Input, &Output, &Setpoint,2,5,1, DIRECT);`
`25`	`25`
`26`	`26`	`int WindowSize 8000 = 5000;`
	`27`	`+int minWindow = 500;`
`27`	`28`	`unsigned long windowStartTime;`
`28`	`29`	`void setup()`
`29`	`30`	`{`
`@@ -42,16 +43,16 @@ void setup()`
`42`	`43`	`void loop()`
`43`	`44`	`{`
`44`	`45`	`Input = analogRead(0);`
`45`		`- myPID.Compute();`
`46`	`46`
`47`	`47`	`/************************************************`
`48`	`48`	`* turn the output pin on/off based on pid output`
`49`	`49`	`************************************************/`
`50`	`50`	`if(millis() - windowStartTime>WindowSize)`
`51`		`- { //time to shift the Relay Window`
	`51`	`+ { //time to shift the Relay Window and recalculate`
`52`	`52`	`windowStartTime += WindowSize;`
	`53`	`+ myPID.Compute();`
`53`	`54`	`}`
`54`		`- if(Output < millis() - windowStartTime) digitalWrite(RelayPin,HIGH);`
	`55`	`+ if(Output > minWindow && Output < millis() - windowStartTime) digitalWrite(RelayPin,HIGH);`
`55`	`56`	`else digitalWrite(RelayPin,LOW);`
`56`	`57`
`57`	`58`	`}`