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dee30a3 Sep 2, 2018
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//
// FILE: dht.h
// AUTHOR: Rob Tillaart
// VERSION: 0.1.29
// PURPOSE: DHT Temperature & Humidity Sensor library for Arduino
// URL: http://arduino.cc/playground/Main/DHTLib
//
// HISTORY:
// see dht.cpp file
//
#ifndef dht_h
#define dht_h
#if ARDUINO < 100
#include <WProgram.h>
#include <pins_arduino.h> // fix for broken pre 1.0 version - TODO TEST
#else
#include <Arduino.h>
#endif
#define DHT_LIB_VERSION "0.1.29"
#define DHTLIB_OK 0
#define DHTLIB_ERROR_CHECKSUM -1
#define DHTLIB_ERROR_TIMEOUT -2
#define DHTLIB_ERROR_CONNECT -3
#define DHTLIB_ERROR_ACK_L -4
#define DHTLIB_ERROR_ACK_H -5
#define DHTLIB_DHT11_WAKEUP 18
#define DHTLIB_DHT_WAKEUP 1
#define DHTLIB_DHT11_LEADING_ZEROS 1
#define DHTLIB_DHT_LEADING_ZEROS 6
// max timeout is 100 usec.
// For a 16 Mhz proc 100 usec is 1600 clock cycles
// loops using DHTLIB_TIMEOUT use at least 4 clock cycli
// so 100 us takes max 400 loops
// so by dividing F_CPU by 40000 we "fail" as fast as possible
#ifndef F_CPU
#define DHTLIB_TIMEOUT 1000 // ahould be approx. clock/40000
#else
#define DHTLIB_TIMEOUT (F_CPU/40000)
#endif
class dht
{
public:
dht() { _disableIRQ = false; };
// return values:
// DHTLIB_OK
// DHTLIB_ERROR_CHECKSUM
// DHTLIB_ERROR_TIMEOUT
// DHTLIB_ERROR_CONNECT
// DHTLIB_ERROR_ACK_L
// DHTLIB_ERROR_ACK_H
int8_t read11(uint8_t pin);
int8_t read(uint8_t pin);
int8_t read12(uint8_t pin);
inline int8_t read21(uint8_t pin) { return read(pin); };
inline int8_t read22(uint8_t pin) { return read(pin); };
inline int8_t read33(uint8_t pin) { return read(pin); };
inline int8_t read44(uint8_t pin) { return read(pin); };
inline int8_t read2301(uint8_t pin) { return read(pin); };
inline int8_t read2302(uint8_t pin) { return read(pin); };
inline int8_t read2303(uint8_t pin) { return read(pin); };
inline int8_t read2320(uint8_t pin) { return read(pin); };
inline int8_t read2322(uint8_t pin) { return read(pin); };
bool getDisableIRQ() { return _disableIRQ; };
void setDisableIRQ(bool b ) { _disableIRQ = b; };
float humidity;
float temperature;
private:
uint8_t bits[5]; // buffer to receive data
int8_t _readSensor(uint8_t pin, uint8_t wakeupDelay, uint8_t leadingZeroBits);
bool _disableIRQ;
};
#endif
//
// END OF FILE
//