lucybrew.ino

// I´m arduino user, not a former programmer. If you have a better approach for brewery, do it!!
// If you found bugs, fix it and ping me. :)

//Libraries
#include <OneWire.h>
#include <DallasTemperature.h>
#include <PID_v1.h>

//Pin 2 for OneWire
//Pin 6 for Heat Element
//Pin 7 for Pump
#define sensorPin 2
#define kettlePin 6
#define pumpPin   7

//PID Variables
double setpoint=25, input, output ;
int   windowSize = 5000, kp=573.85, ki=1.13, kd=0 ;
boolean heat, pump, boil, status;
String blockMessage, inString;
unsigned long  windowStartTime, now;
PID myPID(&input, &output, &setpoint, kp, ki, kd, DIRECT) ;

//OneWire
OneWire oneWire(sensorPin);
DallasTemperature sensors(&oneWire);

//Debug (set true of false)
int debug = true ;

void setup(void) {
        Serial.begin(9600);
        sensors.begin();
        myPID.SetOutputLimits(0, windowSize);
        myPID.SetMode(AUTOMATIC) ;
        pinMode(kettlePin, OUTPUT);
        pinMode(pumpPin,   OUTPUT);
}


void loop() {
        serialReceive();
        evaluate();
        serialOutput();
}


void serialReceive() {
        //todo
        //s == ajuste de setpoint
        if(Serial.available()) {
        char inChar = Serial.read();
        Serial.flush();
        switch (inChar) {
                case 'p':
                if(pump) {
                        digitalWrite(pumpPin,LOW);
                        pump = false;
                }
                else {
                        digitalWrite(pumpPin,HIGH);
                        pump = true;
                }
                break;
                case '+':
                        setpoint = setpoint + 0.5 ;
                break;
                case '-':
                        setpoint = setpoint - 0.5;
                break;
                case 'h':
                        if (boil) {
                                boil = false;
                        }
                        else {
                                boil = true;
                        }
                break;
                case 'd':
                        if (debug) {
                                debug = false ;
                        }
                        else {
                        debug = true;
                        }
                break;
                        case 'o':
                                if(status) {
                                        status = false;
                                }
                                else {
                                        status = true;
                                }
                        break;
                        case 's':
                                newSetPoint();
                        break;
                default:
                break;
                }
        }
}

void evaluate() {
        now = millis();
        sensors.requestTemperatures();
        input = sensors.getTempCByIndex(0);
        myPID.Compute();
        if(now - windowStartTime>windowSize) {
                 windowStartTime += windowSize;
        }
    if(output > now - windowStartTime){
                if(!status) {
                        digitalWrite(kettlePin,LOW);
                        heat = 0;
                }
                else{
                        digitalWrite(kettlePin,HIGH);
                heat = 1;
                }
        }
        else {
                if(boil && status) {
                digitalWrite(kettlePin,HIGH);
                heat = 1;
        }
        else {
                digitalWrite(kettlePin,LOW);
                heat = 0;
        }
        }
}

void serialOutput() {
        Serial.print("Input: ");
        Serial.print(input);
        Serial.print(" SP: ");
        Serial.print(setpoint);
        Serial.print(" Heat: ");
        Serial.print(heat);
        Serial.print(" Pump: ");
        Serial.print(pump);
        Serial.print(" Boil: ");
        Serial.print(boil);
        Serial.print(" Status: ");
        Serial.print(status);
        // For tuning and debug
        if(debug) {
                Serial.print( " Output: ") ;
                Serial.print(output) ;
                Serial.print(" Now: ");
                Serial.print(now - windowStartTime);
        }
        Serial.println();
}

void newSetPoint() {
        while (Serial.available() > 0) {
        int     inChar = Serial.read();
        if (isDigit(inChar)) {
                inString += (char)inChar;
        }
        if (inChar == 'z') {
                Serial.flush();
                        setpoint = (inString.toInt());
                        output = 0    ;
                        inString = " ";
        }
        }
}