Bosch BMA180 3-axis accelerometer driver.

This file contains functions for initializing and reading data from a Bosch BMA180 3-axis accelerometer.

#include "bma180.h"
#include "bma_axis.inc.c"

Functions
static bool	bma180_device_id (sensor_hal_t hal, sensor_data_t data)
	Read BMA180 device ID and revision numbers. More...

static bool	bma180_get_accel (sensor_hal_t hal, sensor_data_t data)
	Read accelerometer data. More...

static bool	bma180_get_temperature (sensor_hal_t hal, sensor_data_t data)
	Read BMA180 integrated temperature sensor data. More...

bool	bma180_init (sensor_t *sensor, int resvd)
	Bosch BMA180 accelerometer driver initialization. More...

static bool	bma180_ioctl (sensor_t sensor, sensor_command_t cmd, void arg)
	BMA180 ioctl control entry point. More...

static bool	bma180_read (sensor_t sensor, sensor_read_t type, sensor_data_t data)
	Read sensor data. More...

static bool	bma180_set_bandwidth (sensor_hal_t *hal, int16_t band)
	Set the BMA180 ADC output data bandwidth. More...

static bool	bma180_set_range (sensor_hal_t *hal, int16_t range)
	Set the BMA180 full scale acceleration range. More...

static bool	bma180_set_state (sensor_hal_t *hal, sensor_state_t state)
	Set the BMA180 execution mode. More...

Variables
static const sensor_map_t	band_table []
	Bosch BMA180 Bandwidth Table (hertz, register value) More...

static const sensor_map_t	range_table []
	Bosch BMA180 Range Table (milli-g, register value) More...

static bool bma180_device_id	(	sensor_hal_t *	hal,
		sensor_data_t *	data
	)

static

Read BMA180 device ID and revision numbers.

This function reads the accelerometer hardware identification registers and returns these values in the specified data structure.

Parameters

hal	Address of an initialized sensor hardware descriptor.
data	Address of sensor_data_t structure to return values.

Returns: bool true if the call succeeds, else false is returned.

References BMA180_CHIP_ID, BMA180_CHIP_VERSION, sensor_data_t::device, and sensor_bus_get.

Referenced by bma180_read().

static bool bma180_get_accel	(	sensor_hal_t *	hal,
		sensor_data_t *	data
	)

static

Read accelerometer data.

This function obtains accelerometer data for all three axes of the Bosch device. The data is read from six device registers using a multi-byte bus transfer. The 10-bit raw results are then assembled from the two register values for each axis, including extending the sign bit, to form a signed 32-bit value.

Along with the actual sensor data, the LSB byte contains a "new" flag indicating if the data for this axis has been updated since the last time the axis data was read. Reading either LSB or MSB data will clear this flag.

Parameters

hal	Address of an initialized sensor hardware descriptor.
data	The address of a vector storing sensor axis data.

Returns: bool true if the call succeeds, else false is returned.

References sensor_hal::burst_addr, and sensor_bus_read.

Referenced by bma180_ioctl(), and bma180_read().

static bool bma180_get_temperature	(	sensor_hal_t *	hal,
		sensor_data_t *	data
	)

static

Read BMA180 integrated temperature sensor data.

Parameters

hal	Address of an initialized sensor hardware descriptor.
data	The address where temperature samples are returned.

Returns: bool true if the call succeeds, else false is returned.

References BMA180_TEMP, BMA180_TEMP_OFFSET, sensor_hal::bus, sensor_data_t::scaled, sensor_bus_get, bus_desc_t::status, STATUS_OK, and sensor_data_t::temperature.

Referenced by bma180_read().

bool bma180_init	(	sensor_t *	sensor,
		int	resvd
	)

Bosch BMA180 accelerometer driver initialization.

This is the main initialization function for the BMA180 device. The accelerometer range and bandwidth are set based on user-specified values from the system configuration.

Parameters

sensor	Address of a sensor device descriptor.
resvd	Reserved value.

Returns: bool true if the call succeeds, else false is returned.

References ARRAYSIZE, band_table, sensor_hal::bandwidth, BMA180_ACC_X_LSB, BMA180_CHIP_ID, BMA180_DATA_RESOLUTION, BMA180_ID_VAL, bma180_ioctl(), bma180_read(), bma180_set_bandwidth(), bma180_set_range(), sensor_hal::burst_addr, sensor_hal::bus, sensor_desc::drv, sensor_device_t::func, sensor_desc::hal, sensor_hal::range, range_table, sensor_funcs_t::read, sensor_hal::resolution, sensor_bus_get, SENSOR_CAPS_3_AXIS, SENSOR_CAPS_AUX_TEMP, SENSOR_CAPS_HI_G_EVENT, SENSOR_CAPS_LO_G_EVENT, SENSOR_CAPS_SELFTEST, SENSOR_SCALE_milli, SENSOR_UNITS_g0, SENSOR_VENDOR_BOSCH, status, bus_desc_t::status, and STATUS_OK.

static bool bma180_ioctl	(	sensor_t *	sensor,
		sensor_command_t	cmd,
		void *	arg
	)

static

BMA180 ioctl control entry point.

Parameters

hal	Address of an initialized sensor hardware descriptor.
cmd	Command to execute
arg	Argument for command (varies)

Returns: bool true if the call succeeds, else false is returned.

References sensor_data_t::axis, bma180_get_accel(), bma180_set_bandwidth(), bma180_set_range(), bma180_set_state(), sensor_desc::err, sensor_desc::hal, sensor_data_t::scaled, SENSOR_ERR_UNSUPPORTED, SENSOR_READ_VECTOR, SENSOR_SET_BANDWIDTH, SENSOR_SET_RANGE, SENSOR_SET_STATE, vector3_t::x, vector3_t::y, and vector3_t::z.

Referenced by bma180_init().

static bool bma180_read	(	sensor_t *	sensor,
		sensor_read_t	type,
		sensor_data_t *	data
	)

static

Read sensor data.

This routine calls the appropriate internal data function to obtain the specified type of data from the sensor device.

Parameters

sensor	Address of an initialized sensor device descriptor.
type	Type of sensor data to read.
data	The address where data values are returned.

Returns: bool true if the call succeeds, else false is returned.

References bma180_device_id(), bma180_get_accel(), bma180_get_temperature(), sensor_desc::err, sensor_desc::hal, SENSOR_ERR_FUNCTION, SENSOR_READ_ACCELERATION, SENSOR_READ_ID, and SENSOR_READ_TEMPERATURE.

Referenced by bma180_init().

static bool bma180_set_bandwidth	(	sensor_hal_t *	hal,
		int16_t	band
	)

static

Set the BMA180 ADC output data bandwidth.

Parameters

hal	Address of an initialized sensor hardware descriptor.
band	The index of a driver-specific bandwidth table entry.

Returns: bool true if the call succeeds, else false is returned.

References BMA180_BW_TCS, BW, sensor_bus_get, and sensor_bus_put.

Referenced by bma180_init(), and bma180_ioctl().

static bool bma180_set_range	(	sensor_hal_t *	hal,
		int16_t	range
	)

static

Set the BMA180 full scale acceleration range.

Parameters

hal	Address of an initialized sensor hardware descriptor.
range	The index o a driver-specific range table entry.

Returns: bool true if the call succeeds, else false is returned.

References BMA180_OFFSET_LSB1, RANGE, sensor_bus_get, and sensor_bus_put.

Referenced by bma180_init(), and bma180_ioctl().

static bool bma180_set_state	(	sensor_hal_t *	hal,
		sensor_state_t	state
	)

static

Set the BMA180 execution mode.

Parameters

hal	Address of an initialized sensor hardware descriptor.
state	A specified sensor operational state.

Returns: bool true if the call succeeds, else false is returned.

Referenced by bma180_ioctl().

const sensor_map_t band_table[]

static

Initial value:

= {
    {{ 10}, BW_10HZ }, {{  20}, BW_20HZ  },
    {{ 40}, BW_40HZ }, {{  75}, BW_75HZ  },
    {{150}, BW_150HZ}, {{ 300}, BW_300HZ },
    {{600}, BW_600HZ}, {{1200}, BW_1200HZ}
}

Bosch BMA180 Bandwidth Table (hertz, register value)

Referenced by bma180_init().

const sensor_map_t range_table[]

static

Initial value:

= {
    {{ 1000}, BMA180_RANGE_1G}, {{1500}, BMA180_RANGE_1_5G},
    {{ 2000}, BMA180_RANGE_2G}, {{3000}, BMA180_RANGE_3G},
    {{ 4000}, BMA180_RANGE_4G}, {{8000}, BMA180_RANGE_8G},
    {{16000}, BMA180_RANGE_16G}
}

Bosch BMA180 Range Table (milli-g, register value)

Referenced by bma180_init().

Microchip® Advanced Software Framework

Functions

Variables