Adafruit_INA219.h

/*!
 * @file Adafruit_INA219.h
 *
 * This is a library for the Adafruit INA219 breakout board
 * ----> https://www.adafruit.com/products/904
 * 
 * Adafruit invests time and resources providing this open source code, 
 * please support Adafruit and open-source hardware by purchasing 
 * products from Adafruit!
 *
 * Written by Kevin "KTOWN" Townsend for Adafruit Industries.
 *
 * BSD license, all text here must be included in any redistribution.
 *
 */

#ifndef _LIB_ADAFRUIT_INA219_
#define _LIB_ADAFRUIT_INA219_

#if ARDUINO >= 100
 #include "Arduino.h"
#else
 #include "WProgram.h"
#endif

#include <Wire.h>

/**************************************************************************/
/*! 
    @brief  default I2C address
*/
/**************************************************************************/
    #define INA219_ADDRESS                         (0x40)    // 1000000 (A0+A1=GND)

/**************************************************************************/
/*! 
    @brief  read
*/
/**************************************************************************/
    #define INA219_READ                            (0x01)

/*=========================================================================
    CONFIG REGISTER (R/W)
    -----------------------------------------------------------------------*/

/**************************************************************************/
/*! 
    @brief  config register address
*/
/**************************************************************************/
    #define INA219_REG_CONFIG                      (0x00)
    /*---------------------------------------------------------------------*/

/**************************************************************************/
/*! 
    @brief  reset bit
*/
/**************************************************************************/
    #define INA219_CONFIG_RESET                    (0x8000)  // Reset Bit

/**************************************************************************/
/*! 
    @brief  mask for bus voltage range
*/
/**************************************************************************/
    #define INA219_CONFIG_BVOLTAGERANGE_MASK       (0x2000)  // Bus Voltage Range Mask

/**************************************************************************/
/*! 
    @brief  bus voltage range values
*/
/**************************************************************************/
enum{
    INA219_CONFIG_BVOLTAGERANGE_16V =        (0x0000),  // 0-16V Range
    INA219_CONFIG_BVOLTAGERANGE_32V =        (0x2000),  // 0-32V Range
};

/**************************************************************************/
/*! 
    @brief  mask for gain bits
*/
/**************************************************************************/
    #define INA219_CONFIG_GAIN_MASK                (0x1800)  // Gain Mask

/**************************************************************************/
/*! 
    @brief  values for gain bits
*/
/**************************************************************************/
enum{
    INA219_CONFIG_GAIN_1_40MV        =       (0x0000),  // Gain 1, 40mV Range
    INA219_CONFIG_GAIN_2_80MV        =       (0x0800),  // Gain 2, 80mV Range
    INA219_CONFIG_GAIN_4_160MV       =       (0x1000),  // Gain 4, 160mV Range
    INA219_CONFIG_GAIN_8_320MV       =       (0x1800),  // Gain 8, 320mV Range
  };
	
  /**************************************************************************/
/*! 
    @brief  mask for bus ADC resolution bits
*/
/**************************************************************************/
    #define INA219_CONFIG_BADCRES_MASK             (0x0780)  // Bus ADC Resolution Mask

/**************************************************************************/
/*! 
    @brief  values for bus ADC resolution
*/
/**************************************************************************/
enum {
    INA219_CONFIG_BADCRES_9BIT       =       (0x0000),  // 9-bit bus res = 0..511
    INA219_CONFIG_BADCRES_10BIT      =       (0x0080),  // 10-bit bus res = 0..1023
    INA219_CONFIG_BADCRES_11BIT      =       (0x0100),  // 11-bit bus res = 0..2047
    INA219_CONFIG_BADCRES_12BIT       =      (0x0180),  // 12-bit bus res = 0..4097
};

/**************************************************************************/
/*! 
    @brief  mask for shunt ADC resolution bits
*/
/**************************************************************************/  
    #define INA219_CONFIG_SADCRES_MASK             (0x0078)  // Shunt ADC Resolution and Averaging Mask

/**************************************************************************/
/*! 
    @brief  values for shunt ADC resolution
*/
/**************************************************************************/
enum {
    INA219_CONFIG_SADCRES_9BIT_1S_84US     = (0x0000),  // 1 x 9-bit shunt sample
    INA219_CONFIG_SADCRES_10BIT_1S_148US   = (0x0008),  // 1 x 10-bit shunt sample
    INA219_CONFIG_SADCRES_11BIT_1S_276US   = (0x0010),  // 1 x 11-bit shunt sample
    INA219_CONFIG_SADCRES_12BIT_1S_532US   = (0x0018),  // 1 x 12-bit shunt sample
    INA219_CONFIG_SADCRES_12BIT_2S_1060US  = (0x0048),	 // 2 x 12-bit shunt samples averaged together
    INA219_CONFIG_SADCRES_12BIT_4S_2130US  = (0x0050),  // 4 x 12-bit shunt samples averaged together
    INA219_CONFIG_SADCRES_12BIT_8S_4260US  = (0x0058),  // 8 x 12-bit shunt samples averaged together
    INA219_CONFIG_SADCRES_12BIT_16S_8510US = (0x0060),  // 16 x 12-bit shunt samples averaged together
    INA219_CONFIG_SADCRES_12BIT_32S_17MS   = (0x0068),  // 32 x 12-bit shunt samples averaged together
    INA219_CONFIG_SADCRES_12BIT_64S_34MS   = (0x0070),  // 64 x 12-bit shunt samples averaged together
    INA219_CONFIG_SADCRES_12BIT_128S_69MS =  (0x0078),  // 128 x 12-bit shunt samples averaged together
};

/**************************************************************************/
/*! 
    @brief  mask for operating mode bits
*/
/**************************************************************************/
    #define INA219_CONFIG_MODE_MASK                (0x0007)  // Operating Mode Mask

/**************************************************************************/
/*! 
    @brief  values for operating mode
*/
/**************************************************************************/
 enum {   
    INA219_CONFIG_MODE_POWERDOWN          =  (0x0000),
    INA219_CONFIG_MODE_SVOLT_TRIGGERED    =  (0x0001),
    INA219_CONFIG_MODE_BVOLT_TRIGGERED    =  (0x0002),
    INA219_CONFIG_MODE_SANDBVOLT_TRIGGERED = (0x0003),
    INA219_CONFIG_MODE_ADCOFF             =  (0x0004),
    INA219_CONFIG_MODE_SVOLT_CONTINUOUS  =  (0x0005),
    INA219_CONFIG_MODE_BVOLT_CONTINUOUS   =  (0x0006),
    INA219_CONFIG_MODE_SANDBVOLT_CONTINUOUS = (0x0007),	
};
/*=========================================================================*/

/**************************************************************************/
/*! 
    @brief  shunt voltage register
*/
/**************************************************************************/
    #define INA219_REG_SHUNTVOLTAGE                (0x01)
/*=========================================================================*/

/**************************************************************************/
/*! 
    @brief  bus voltage register
*/
/**************************************************************************/
    #define INA219_REG_BUSVOLTAGE                  (0x02)
/*=========================================================================*/

/**************************************************************************/
/*! 
    @brief  power register
*/
/**************************************************************************/
    #define INA219_REG_POWER                       (0x03)
/*=========================================================================*/

/**************************************************************************/
/*! 
    @brief  current register
*/
/**************************************************************************/
    #define INA219_REG_CURRENT                     (0x04)
/*=========================================================================*/

/**************************************************************************/
/*! 
    @brief  calibration register
*/
/**************************************************************************/
    #define INA219_REG_CALIBRATION                 (0x05)
/*=========================================================================*/

/**************************************************************************/
/*! 
    @brief  Class that stores state and functions for interacting with INA219 current/power monitor IC
*/
/**************************************************************************/
class Adafruit_INA219{
 public:
  Adafruit_INA219(uint8_t addr = INA219_ADDRESS);
  void begin(void);
  void begin(TwoWire *theWire);
  void setCalibration_32V_2A(void);
  void setCalibration_32V_1A(void);
  void setCalibration_16V_400mA(void);
  void setCalibration_Ext_16V_75mV_50A(void);
  float getBusVoltage_V(void);
  float getShuntVoltage_mV(void);
  float getCurrent_mA(void);
  float getPower_mW(void);

 private:
  TwoWire *_i2c;

  uint8_t ina219_i2caddr;
  uint32_t ina219_calValue;
  // The following multipliers are used to convert raw current and power
  // values to mA and mW, taking into account the current config settings
  uint32_t ina219_currentDivider_mA;
  uint32_t ina219_powerMultiplier_mW;

  void init();
  void wireWriteRegister(uint8_t reg, uint16_t value);
  void wireReadRegister(uint8_t reg, uint16_t *value);
  int16_t getBusVoltage_raw(void);
  int16_t getShuntVoltage_raw(void);
  int16_t getCurrent_raw(void);
  int16_t getPower_raw(void);
};

#endif