SHTC3.h

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#ifndef _H_ARDUINO_SHTC3_H_
#define _H_ARDUINO_SHTC3_H_
 
#include <Arduino.h>
#include <Wire.h>
 
// Uncomment this for no float operation
//#define ARDUINO_SHTC3_NOFLOAT   1
 
#define SHTC3_RESET_DELAY_US (255)
 
typedef TwoWire arduino_shtc3_wire_t;
 
enum shtc3_cmds_t
{
    SHTC3_SLEEP = 0xB098,
    SHTC3_WAKEUP = 0x3517,
    SHTC3_RESET = 0x805D,
    SHTC3_ID = 0xEFC8,
    SHTC3_READ = 0x7CA2,   // T first + Clock streching
    SHTC3_READ_LP = 0x6458 // T first + Clock streching + Low power
};
 
class SHTC3
{
  public:
    SHTC3(arduino_shtc3_wire_t &w = Wire) : _wire(w), _t(0), _h(0)
    {
    }
 
    bool begin(bool do_sample = false);
    bool sample(uint16_t readcmd = SHTC3_READ_LP, uint8_t pause = 0);
#if defined(ARDUINO_SHTC3_NOFLOAT)
    int16_t readTempC();
    uint16_t readHumidity();
#else
    float readTempC();
    float readHumidity();
#endif
 
    inline bool sleep()
    {
        return twiCommand(SHTC3_SLEEP);
    }
    inline bool wakeup()
    {
        bool b = twiCommand(SHTC3_WAKEUP);
        delayMicroseconds(SHTC3_RESET_DELAY_US);
        return b;
    }
    inline bool reset()
    {
        bool b = twiCommand(SHTC3_RESET);
        delayMicroseconds(SHTC3_RESET_DELAY_US);
        return b;
    }
 
    bool twiCommand(uint16_t cmd, uint8_t stop = true);
    bool twiTransfer(uint16_t cmd, uint8_t *data, uint8_t len, uint8_t pause = 0);
 
  private:
    // Properties
    arduino_shtc3_wire_t &_wire;
    uint16_t _t;
    uint16_t _h;
    // Private methods
    inline bool checkCRC(const uint8_t *data)
    {
        return crc8(data, 2) == data[2];
    }
    uint8_t crc8(const uint8_t *data, uint8_t len);
};
 
 
#endif