accelerometer-mma8652fc.h

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#ifndef DRIVER_ACCELEROMETER_MMA8652FC_H
#define DRIVER_ACCELEROMETER_MMA8652FC_H
/**********************************************************************/
/**
 * @file
 * @brief Driver for accelerometer MMA8652FC
 *
 * @author AMO, Jetro as
 ***********************************************************************/
#include <dev/i2c-master.h>
#include <sys/clock.h>

/**
 * \defgroup mma8652fc MMA8652FC accelerometer
 * \ingroup extdrv
 * \{
 *
 * Functionality included:
 * - Reset accelerometer
 *   All registers in the accelerometer is set to default value
 * - Enable or disable accelerometer
 * - Read Acceleration x, y and z value
 */

/***********************************************************************
    Global definitions
***********************************************************************/
/**
 * accel_gravity_t structure defines the X, Y Z result
 *
 */
struct accel_gravity_t
{
  int16_t  GravityX;        // Resolution 1m g
  int16_t  GravityY;        // Resolution 1m g
  int16_t  GravityZ;        // Resolution 1m g
};

enum accel_odr_t {ODR_800_HZ, ODR_400_HZ, ODR_200_HZ, ODR_100_HZ, ODR_50_HZ, ODR_12_5_HZ, ODR_6_25_HZ, ODR_1_56_HZ};

// > 2/ODR + 1 ms  (0.5 ms = extra time)
#define DELAY_800_HZ  MS_TO_TICKS((clock_time_t)((float)2*1000/800 + 1 + (float)0.5) + 1)
#define DELAY_400_HZ  MS_TO_TICKS((clock_time_t)((float)2*1000/400 + 1 + (float)0.5) + 1)
#define DELAY_200_HZ  MS_TO_TICKS((clock_time_t)((float)2*1000/200 + 1 + (float)0.5) + 1)
#define DELAY_100_HZ  MS_TO_TICKS((clock_time_t)((float)2*1000/100 + 1 + (float)0.5) + 1)
#define DELAY_50_HZ   MS_TO_TICKS((clock_time_t)((float)2*1000/50 + 1 + (float)0.5) + 1)
#define DELAY_12_5_HZ MS_TO_TICKS((clock_time_t)((float)2*1000/12.5 + 1 + (float)0.5) + 1)
#define DELAY_6_25_HZ MS_TO_TICKS((clock_time_t)((float)2*1000/6.25 + 1 + (float)0.5) + 1)
#define DELAY_1_56_HZ MS_TO_TICKS((clock_time_t)((float)2*1000/1.56 + 1 + (float)0.5) + 1)

/**
 * accel_gravity_t structure defines the configuration og the accelerometer
 *
 */
struct accel_config_t
{
  const struct i2c_t *I2c;
  uint8_t SlaveAddress;
  enum accel_odr_t ODR;
  clock_time_t Delay;   // > 2/ODR + 1 ms Warning: The delay time will be longer for lower ODR
};


/**********************************************************************/
/**
 * @brief Name: AccelerometerInterruptCb\n
 * The callback is called in soft irq context by the framework when
 * a hardware interrupt from the accelerometer is received.
 *
 * @param Config    Pointer to configuration of accelerometer
 ***********************************************************************/
extern void AccelerometerInterruptCb(const struct accel_config_t *Config);


/**********************************************************************/
/**
 * @brief Name: ResetAccelerometer\n
 * Reset accelerometer, all registers in the accelerometer is set to
 * default value
 *
 * @param Config    Pointer to configuration of accelerometer
 * @return true if OK, else false
 ***********************************************************************/
extern bool ResetAccelerometer(const struct accel_config_t *Config);


/**********************************************************************/
/**
 * @brief Name: EnableAccelerometer\n
 *  Output data is not high pass filtered
 *  ±2 g mode, sensitivity = 1024 counts/g
 *  Sleep mode rates 50 Hz
 *  System output data rate (ODR) defined in Board.c
 *
 * @param Config    Pointer to configuration of accelerometer
 * @param Enable if true then enable, if false then disable
 * @return true if OK, else false
 ***********************************************************************/
bool EnableAccelerometer(const struct accel_config_t *Config, bool Enable);


/**********************************************************************/
/**
 * @brief Name: ReadAccelerometer\n
 * Read Acceleration x, y and z value
 *
 * @param Config    Pointer to configuration of accelerometer
 * @param Result    pointer for the result
 * @return true if OK and false if error or if data is not ready
 ***********************************************************************/
extern bool ReadAccelerometer(const struct accel_config_t *Config, struct accel_gravity_t *Result);

/** \} */

#endif // DRIVER_ACCELEROMETER_MMA8652FC_H