enhance coding style Examples

examples/PID_AdaptiveTunings/PID_AdaptiveTunings.ino

@@ -11,6 +11,9 @@
 
 #include <PID_v1.h>
 
+#define PIN_INPUT 0
+#define PIN_OUTPUT 3
+
 //Define Variables we'll be connecting to
 double Setpoint, Input, Output;
 
@@ -24,7 +27,7 @@ PID myPID(&Input, &Output, &Setpoint, consKp, consKi, consKd, DIRECT);
 void setup()
 {
   //initialize the variables we're linked to
-  Input = analogRead(0);
+  Input = analogRead(PIN_INPUT);
   Setpoint = 100;
 
   //turn the PID on
@@ -33,10 +36,10 @@ void setup()
 
 void loop()
 {
-  Input = analogRead(0);
-  
+  Input = analogRead(PIN_INPUT);
+
   double gap = abs(Setpoint-Input); //distance away from setpoint
-  if(gap<10)
+  if (gap < 10)
   {  //we're close to setpoint, use conservative tuning parameters
     myPID.SetTunings(consKp, consKi, consKd);
   }
@@ -45,9 +48,9 @@ void loop()
      //we're far from setpoint, use aggressive tuning parameters
      myPID.SetTunings(aggKp, aggKi, aggKd);
   }
-  
+
   myPID.Compute();
-  analogWrite(3,Output);
+  analogWrite(PIN_OUTPUT, Output);
 }
 
 

examples/PID_Basic/PID_Basic.ino

@@ -5,16 +5,20 @@
 
 #include <PID_v1.h>
 
+#define PIN_INPUT 0
+#define PIN_OUTPUT 3
+
 //Define Variables we'll be connecting to
 double Setpoint, Input, Output;
 
 //Specify the links and initial tuning parameters
-PID myPID(&Input, &Output, &Setpoint,2,5,1, DIRECT);
+double Kp=2, Ki=5, Kd=1;
+PID myPID(&Input, &Output, &Setpoint, Kp, Ki, Kd, DIRECT);
 
 void setup()
 {
   //initialize the variables we're linked to
-  Input = analogRead(0);
+  Input = analogRead(PIN_INPUT);
   Setpoint = 100;
 
   //turn the PID on
@@ -23,9 +27,9 @@ void setup()
 
 void loop()
 {
-  Input = analogRead(0);
+  Input = analogRead(PIN_INPUT);
   myPID.Compute();
-  analogWrite(3,Output);
+  analogWrite(PIN_OUTPUT, Output);
 }
 
 

examples/PID_RelayOutput/PID_RelayOutput.ino

@@ -7,28 +7,32 @@
  *
  *   to connect them together we use "time proportioning
  * control"  it's essentially a really slow version of PWM.
- * first we decide on a window size (5000mS say.) we then 
+ * first we decide on a window size (5000mS say.) we then
  * set the pid to adjust its output between 0 and that window
  * size.  lastly, we add some logic that translates the PID
- * output into "Relay On Time" with the remainder of the 
+ * output into "Relay On Time" with the remainder of the
  * window being "Relay Off Time"
  ********************************************************/
 
 #include <PID_v1.h>
-#define RelayPin 6
+
+#define PIN_INPUT 0
+#define RELAY_PIN 6
 
 //Define Variables we'll be connecting to
 double Setpoint, Input, Output;
 
 //Specify the links and initial tuning parameters
-PID myPID(&Input, &Output, &Setpoint,2,5,1, DIRECT);
+double Kp=2, Ki=5, Kd=1;
+PID myPID(&Input, &Output, &Setpoint, Kp, Ki, Kd, DIRECT);
 
 int WindowSize = 5000;
 unsigned long windowStartTime;
+
 void setup()
 {
   windowStartTime = millis();
-  
+
   //initialize the variables we're linked to
   Setpoint = 100;
 
@@ -41,18 +45,18 @@ void setup()
 
 void loop()
 {
-  Input = analogRead(0);
+  Input = analogRead(PIN_INPUT);
   myPID.Compute();
 
   /************************************************
    * turn the output pin on/off based on pid output
    ************************************************/
-  if(millis() - windowStartTime>WindowSize)
+  if (millis() - windowStartTime > WindowSize)
   { //time to shift the Relay Window
     windowStartTime += WindowSize;
   }
-  if(Output < millis() - windowStartTime) digitalWrite(RelayPin,HIGH);
-  else digitalWrite(RelayPin,LOW);
+  if (Output < millis() - windowStartTime) digitalWrite(RELAY_PIN, HIGH);
+  else digitalWrite(RELAY_PIN, LOW);
 
 }