autotune.ino

#include <PID_v1.h>
#include <PID_AutoTune_v0.h>
#include <OneWire.h>
#include <DallasTemperature.h>
//Pins
#define RelayPin 6
#define ONE_WIRE_BUS 2
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

double aTuneStep=2500, aTuneNoise=1, aTuneStartValue=2500;
double input, output, setpoint=35, kp=0, ki=0, kd=0;
int windowSize = 5000 ;
unsigned long  windowStartTime, now;
int heat ;
byte ATuneModeRemember=2;
unsigned int aTuneLookBack=20;
boolean tuning = true;
int serialTime;
PID myPID(&input, &output, &setpoint,kp,ki,kd, DIRECT);
PID_ATune aTune(&input, &output);


void setup()
{
  //Setup the pid
  myPID.SetMode(AUTOMATIC);
  if(tuning)
  {
    tuning=false;
    changeAutoTune();
    tuning=true;
  }
  serialTime = 0;
  Serial.begin(9600);
  sensors.begin();
  windowStartTime - millis();
  myPID.SetOutputLimits(0, windowSize);
  myPID.SetMode(AUTOMATIC) ;
  pinMode(RelayPin, OUTPUT);
}

void loop()
{

  now = millis();
  sensors.requestTemperatures();
  input = sensors.getTempCByIndex(0);
  if(tuning)
  {
    byte val = (aTune.Runtime());
    if (val!=0)
    {
      tuning = false;
    }
    if(!tuning)
    {
      kp = aTune.GetKp();
      ki = aTune.GetKi();
      kd = aTune.GetKd();
      myPID.SetTunings(kp,ki,kd);
      AutoTuneHelper(false);
    }
  }
  else myPID.Compute();
  if(now - windowStartTime>windowSize)
  {
    windowStartTime += windowSize;
  }
  if(output > now - windowStartTime) {
     digitalWrite(RelayPin,HIGH);
     heat = 1 ;
  }
  else {
    digitalWrite(RelayPin,LOW);
     heat = 0 ;
  }
        SerialSend();
}


void changeAutoTune()
{
 if(!tuning)
  {
    output=aTuneStartValue;
    aTune.SetNoiseBand(aTuneNoise);
    aTune.SetOutputStep(aTuneStep);
    aTune.SetLookbackSec((int)aTuneLookBack);
    AutoTuneHelper(true);
    tuning = true;
  }
  else
  {
    aTune.Cancel();
    tuning = false;
    AutoTuneHelper(false);
  }
}

void AutoTuneHelper(boolean start)
{
  if(start)
    ATuneModeRemember = myPID.GetMode();
  else
    myPID.SetMode(ATuneModeRemember);
}


void SerialSend()
{
 // unsigned long now = millis();
  Serial.print("setpoint: ");Serial.print(setpoint); Serial.print(" ");
  Serial.print("input: ");Serial.print(input); Serial.print(" ");
  Serial.print("output: ");Serial.print(output); Serial.print(" ");
  Serial.print("kp: ");Serial.print(myPID.GetKp());Serial.print(" ");
  Serial.print("ki: ");Serial.print(myPID.GetKi());Serial.print(" ");
  Serial.print("kd: ");Serial.print(myPID.GetKd());Serial.print(" ");
  Serial.print("tuning: ");Serial.print(tuning);Serial.println("");
 // Serial.print("time: ");Serial.print(now);Serial.println();
}

void SerialReceive()
{
  if(Serial.available())
  {
   char b = Serial.read();
   Serial.flush();
   if((b=='1' && !tuning) || (b!='1' && tuning))changeAutoTune();
  }
}