Arduino PID library

PID Library implemented on arduino

Check this link

http://arduino.cc/playground/Code/PIDLibrary

A basic program

 /********************************************************  
  * PID Basic Example  
  * Reading analog input 0 to control analog PWM output 3  
  ********************************************************/  
 #include <PID_v1.h>  
 //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);  
 void setup()  
 {  
  //initialize the variables we're linked to  
  Input = analogRead(0);  
  Setpoint = 100;  
  //turn the PID on  
  myPID.SetMode(AUTOMATIC);  
 }  
 void loop()  
 {  
  Input = analogRead(0);  
  myPID.Compute();  
  analogWrite(3,Output);  
 }  

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