Temperature Sensor

/*
  Temperature Sensor
 Read value from grove-temperature-humidity sensor then display on grove-4-digital-display
 
 The circuit:
 * 4-digital-display attached to pin35 & pin36 (J14 plug on Grove Base BoosterPack)
 * sig pin of the Grove-Temperature-Humidity Sensor to the analog pin 24 (Grove connector J6)
 * one side pin (either one) to ground
 * the other side pin to +VCC
 * LED anode (long leg) attached to RED_LED
 * LED cathode (short leg) attached to ground
 
 * Note: Put your hands on Grove-Temperature-Humidity Sensor, both of the value 
         will rise. 
         
         4-digital-display:
         |--------------------------|
         | temperature :  humidity  |    
         |--------------------------| 
 
 This example code is in the public domain.
 
 http://www.seeedstudio.com/wiki/Grove_-_Temperature_and_Humidity_Sensor_Pro 
 
 */
 
#include "TM1637.h" 
#include "DHT.h"

/* Macro Define */
#define CLK               36                 /* 4-digital display clock pin */
#define DIO               35                 /* 4-digital display data pin */
#define BLINK_LED         RED_LED            /* blink led */
#define TEMP_HUMI_PIN     24                 /* pin of temperature&humidity sensor */
#define ROTARY_ANGLE_P    26                 /* pin of rotary angle sensor */

/* Global Varibles */
TM1637 tm1637(CLK, DIO);                  /* 4-digital display object */
DHT dht(TEMP_HUMI_PIN, DHT22);            /* temperature&humidity sensor object */

int8_t t_bits[2] = {0};                   /* array to store the single bits of the temperature */

int c_threshold = 0;                 /* variable to store the value coming from rotary angle sensor */
int blink_interval = 0;               /* LED delay time */
int8_t bits[4] = {0};                 /* array to store the single bits of the value */

const int buttonPin = PUSH2;     // the number of the pushbutton pin
int buttonState = 0;         // variable for reading the pushbutton status
bool isCelsius = true;
bool wasPressed = false;

/* the setup() method runs once, when the sketch starts */
void setup() {
        
    tm1637.init();                       /* initialize 4-digital display */
    tm1637.set(BRIGHT_TYPICAL);          /* set the brightness */    
    tm1637.point(POINT_ON);              /* light the clock point ":" */
        
    dht.begin();                         /* initialize temperature humidity sensor */
        
    pinMode(RED_LED, OUTPUT);            /* declare the red_led pin as an OUTPUT */
    pinMode(GREEN_LED, OUTPUT);
    pinMode(BLUE_LED, OUTPUT);

    // initialize the pushbutton pin as an input:
    pinMode(buttonPin, INPUT_PULLUP); 
}

int celsiusToFarenheit(int temp){
  return 1.8 * (temp) + 32;
}

/* the loop() method runs over and over again */
void loop() {   
  
    int c_temp = dht.readTemperature();             /* read the temperature value from the sensor */
    c_threshold = analogRead(ROTARY_ANGLE_P) / 128;      /* read the value from the sensor */
    blink_interval = c_threshold;                        /* store the rotary analog value */

    // read the state of the pushbutton value:
    buttonState = digitalRead(buttonPin);

    int f_temp = celsiusToFarenheit(c_temp);
    int f_threshold = celsiusToFarenheit(c_threshold);    
  
    // check if the pushbutton is pressed.
    // if it is, the buttonState is HIGH:
    if (buttonState == HIGH) {     
      wasPressed = true;
    } 
    else {
      if(wasPressed){
        isCelsius = !isCelsius;
      }
      wasPressed = false;
    }
             
    memset(t_bits, 0, 2);                                 /* reset array when we use it */
    memset(bits, 2, 4);

    
    if(isCelsius){
      /* 4-digital-display [0,3] is used to display temperatures */
      t_bits[0] = c_temp % 10;
      c_temp /= 10;
      t_bits[1] = c_temp % 10;
  
      bits[2] = c_threshold % 10;
      c_threshold = c_threshold / 10;
      bits[3] = c_threshold % 10;
    }
    else {
      /* 4-digital-display [0,3] is used to display temperatures */
      t_bits[0] = f_temp % 10;
      f_temp /= 10;
      t_bits[1] = f_temp % 10;
  
      bits[2] = f_threshold % 10;
      f_threshold = f_threshold / 10;
      bits[3] = f_threshold % 10;
    }
    
    
    /* show it */
    tm1637.display(1, t_bits[0]);
    tm1637.display(0, t_bits[1]);
    tm1637.display(3, bits[2]);
    tm1637.display(2, bits[3]);

    if(dht.readTemperature() > analogRead(ROTARY_ANGLE_P) / 128)                       /* too hot for jacket */
    {
      digitalWrite(39, LOW);
      digitalWrite(BLUE_LED, LOW);
      digitalWrite(RED_LED, HIGH);
    }
    else                                                  /* wear a jacket */
    {
      digitalWrite(39, LOW);
      digitalWrite(RED_LED, LOW);
      digitalWrite(BLUE_LED, HIGH);
    }
     
}