BMP085.hh

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#ifndef COSA_BMP085_HH
#define COSA_BMP085_HH

#include "Cosa/Types.h"
#include "Cosa/TWI.hh"
#include "Cosa/IOStream.hh"

class BMP085 : private TWI::Driver {
public:
  enum Mode {
    ULTRA_LOW_POWER = 0,
    STANDARD = 1,
    HIGH_RESOLUTION = 2,
    ULTRA_HIGH_RESOLUTION = 3
  } __attribute__((packed));

  BMP085() :
    TWI::Driver(0x77),
    m_mode(ULTRA_LOW_POWER),
    m_cmd(0),
    m_start(0),
    B5(0),
    m_pressure(0)
  {}

  bool begin(Mode mode = ULTRA_LOW_POWER);

  bool sample_temperature_request();

  bool read_temperature();

  bool sample_temperature()
  {
    return (sample_temperature_request() && read_temperature());
  }

  bool sample_pressure_request();

  bool read_pressure();

  bool sample_pressure()
    __attribute__((always_inline))
  {
    return (sample_pressure_request() && read_pressure());
  }

  bool sample()
    __attribute__((always_inline))
  {
    return (sample_temperature() && sample_pressure());
  }

  int16_t temperature() const
    __attribute__((always_inline))
  {
    return ((B5 + 8) >> 4);
  }

  int32_t pressure() const
  {
    return (m_pressure);
  }

protected:
  static const uint8_t TEMP_CONV_MS = 5;

  static const uint8_t PRESSURE_CONV_MS[] __PROGMEM;

  struct param_t {
    int16_t ac1;
    int16_t ac2;
    int16_t ac3;
    uint16_t ac4;
    uint16_t ac5;
    uint16_t ac6;
    int16_t b1;
    int16_t b2;
    int16_t mb;
    int16_t mc;
    int16_t md;
  };

  static const uint8_t COEFF_REG = 0xAA;

  static const uint8_t CMD_REG = 0xF4;

  static const uint8_t RES_REG = 0xF6;

  static const uint8_t TEMP_CONV_CMD = 0x2E;

  static const uint8_t PRESSURE_CONV_CMD = 0x34;

  param_t m_param;

  Mode m_mode;

  uint8_t m_cmd;

  uint16_t m_start;

  int32_t B5;

  int32_t m_pressure;
};

extern IOStream& operator<<(IOStream& outs, BMP085& bmp);

#endif