/**************************************************************************/
/*
Modified by annawb

This is an Arduino library for SHT21 & HTU21D Digital Humidity & Temperature Sensor

Written by enjoyneering79 https://github.com/enjoyneering/HTU21D
Modified by luetzel for use with SoftwareI2CMaster https://github.com/todbot/SoftI2CMaster 

These sensor uses I2C to communicate, 2 pins are required to interface

Connect HTU21D to pins :  SDA  SCL
Uno, Redboard, Pro:       A4   A5
Mega2560, Due:            20   21
Leonardo:                 2    3

BSD license, all text above must be included in any redistribution
*/
/**************************************************************************/

#include "SoftI2CMaster.h"
#include "HTU21D_SoftI2C.h"

/*
HTU21D(resolution)

resolution:
HTU21D_RES_RH12_TEMP14 - RH: 12Bit, measuring time 16ms. Temperature: 14Bit, measuring time 50ms
HTU21D_RES_RH8_TEMP12  - RH: 8Bit,  measuring time 8ms.  Temperature: 12Bit, measuring time 25ms
HTU21D_RES_RH10_TEMP13 - RH: 10Bit, measuring time 5ms.  Temperature: 13Bit, measuring time 13ms.
HTU21D_RES_RH11_TEMP11 - RH: 11Bit, measuring time 3ms.  Temperature: 11Bit, measuring time 7ms.


DEFAULT
HTU21D(HTU21D_RES_RH12_TEMP14)
*/

//sda = 4; scl = 6 for ATTiny84
//(0, 2) for ATtiny85


#include "SoftI2CMaster.h"
#include "HTU21D_SoftI2C.h"

// constants won't change. They're used here to set pin numbers:
const int fanPin =  2;      // actual fan = 2, LED = 7
int sdaPin = 4;
int sclPin = 6;

// variables will change:
volatile int humidity = 0;         // variable for reading the pushbutton status

SoftI2CMaster i2c = SoftI2CMaster( sclPin, sdaPin, 0 );
HTU21D_SoftI2C myHTU21D = HTU21D_SoftI2C(&i2c);

void setup() {
  Serial.begin(9600);
  pinMode(fanPin, OUTPUT);
}

void loop() {
  requestEvent();
  delay(300); //or works with 100
  humidity = myHTU21D.readHumidity();
  if (humidity > 90) {
      digitalWrite(fanPin, LOW);
    }
  else {
     digitalWrite(fanPin, HIGH);
  }
}

void requestEvent()
{
     Serial.print(F("{\"H\":"));
     Serial.print(myHTU21D.readHumidity());
     Serial.print(F(", \"T\":"));
     Serial.print(myHTU21D.readTemperature());
     Serial.print(F(", \"D\":1"));
     Serial.println(F("}"));
 }