InvenSense IMU-3000 digital triaxial gyroscope.

This module implements a driver for the InvenSense IMU-3000 digital 3-axis MEMS gyroscope and digital motion processor (IMU). The IMU-3000 provides digital-output x-, y-, and z-axis angular rate sensor readings with a sensitivity of 16 LSBs per deg/sec and programmable full-scale ranges of +/-250, +/-500, +/-1000, and +/-2000 deg/sec. The device includes a dedicated I2C master accelerometer sensor bus facilitating direct data acquisition from an off-chip third party accelerometer without intervention from an external processor. A configurable 512 Byte FIFO allows system microcontrollers to burst read the sensor data and then sleep while the IMU collects more data.

#include "imu3000.h"

Data Structures
struct	imu3000_event_t

Macros
#define	IMU3000_RESOLUTION (16)
	Axis data sample resolution (bits) More...

Functions
static bool	imu3000_default_init (sensor_hal_t hal, sensor_hal_t aux)
	InvenSense IMU-3000 gyroscope driver defaults. More...

static bool	imu3000_device_id (sensor_hal_t hal, sensor_data_t data)
	Read gyroscope device ID. More...

static bool	imu3000_event (sensor_t sensor, sensor_event_t sensor_event, sensor_event_callback_t callback, bool enable)
	Enable/disable IMU3000 sensor event. More...

static bool	imu3000_get_rotation (sensor_hal_t hal, sensor_data_t data)
	Read gyroscope angular rate axis data. More...

static bool	imu3000_get_temperature (sensor_hal_t hal, sensor_data_t data)
	Read gyroscope integrated temperature sensor data. More...

bool	imu3000_init (sensor_t *sensor, int resvd)
	InvenSense IMU-3000 motion processor driver initialization. More...

static bool	imu3000_ioctl (sensor_t sensor, sensor_command_t cmd, void arg)
	IMU3000 ioctl control entry point. More...

static void	imu3000_isr (volatile void *arg)
	Invensense IMU3000 driver interrupt service routine. More...

static bool	imu3000_read (sensor_t sensor, sensor_read_t type, sensor_data_t data)
	Read sensor data. More...

static bool	imu3000_set_bandwidth (sensor_hal_t *hal, int16_t band)
	Set the IMU-3000 low-pass filter bandwidth. More...

static bool	imu3000_set_range (sensor_hal_t *hal, int16_t range)
	Set the IMU-3000 full scale range. More...

static bool	imu3000_set_sample_rate (sensor_hal_t *hal, int16_t rate)
	Set the IMU3000 sample rate. More...

static bool	imu3000_set_state (sensor_hal_t *hal, sensor_state_t state)
	Set the IMU-3000 execution mode. More...

Variables
static const sensor_map_t	band_table []
	InvenSense IMU-3000 low-pass Bandwidth Table (hertz, register value) More...

static sensor_event_callback_t	event_cb = {.handler = default_event_handler}
	Sensor Event Callback Descriptor. More...

static const sensor_map_t	range_table []
	InvenSense IMU-3000 Range Table (deg/sec, register value) More...

int16_t const	scale_lsb_per_dps []
	Sensitivity Scale Factors. More...

static int	sensor_dlpf_cfg = 3
	The digital low-pass filter table index defaults to 42 Hz. More...

static int	sensor_fs_sel = 3
	The range table index defaults to 2000 deg/sec full-scale. More...

#define IMU3000_RESOLUTION (16)

Axis data sample resolution (bits)

static bool imu3000_default_init	(	sensor_hal_t *	hal,
		sensor_hal_t *	aux
	)

static

InvenSense IMU-3000 gyroscope driver defaults.

This is a convenience routine for setting the default device configuration during initialization or after reset.

Returns: bool true if the sensor is ready for use, else false.

References bus_desc_t::addr, AUX_ADDR_CLKOUTEN, sensor_hal::burst_addr, sensor_hal::bus, IMU3000_AUX_BURST_ADDR, IMU3000_AUX_SLV_ADDR, IMU3000_DLPF_FS, IMU3000_ID_VAL, IMU3000_PWR_MGM, IMU3000_SMPLRT_DIV, IMU3000_USER_CTRL, IMU3000_WHO_AM_I, IMU3000_X_OFFS_USRH, PWR_MGM_CLK_SEL_Z, PWR_MGM_H_RESET, sensor_map_t::reserved_val, sensor_bus_get, sensor_bus_put, sensor_bus_write, sensor_dlpf_cfg, sensor_fs_sel, status, bus_desc_t::status, STATUS_OK, USER_CTRL_AUX_IF_EN, and USER_CTRL_AUX_IF_RST.

Referenced by imu3000_set_state().

static bool imu3000_device_id	(	sensor_hal_t *	hal,
		sensor_data_t *	data
	)

static

Read gyroscope device ID.

This function reads the gyroscope hardware identification registers and returns these values to the addresses specified in the function parameters.

Parameters

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

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

References sensor_data_t::device, IMU3000_WHO_AM_I, and sensor_bus_get.

Referenced by imu3000_read().

static bool imu3000_event	(	sensor_t *	sensor,
		sensor_event_t	sensor_event,
		sensor_event_callback_t *	callback,
		bool	enable
	)

static

Enable/disable IMU3000 sensor event.

Parameters

sensor	Address of an initialized sensor device descriptor
callback	Application-defined event callback handler descriptor
enable	Enable flag: true = enable event, false = disable event

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

References sensor_desc::hal, IMU3000_INT_CFG, INT_CFG_ANYRD_2CLEAR, INT_CFG_LATCH_INT_EN, INT_CFG_RAW_RDY_EN, sensor_bus_put, SENSOR_EVENT_NEW_DATA, sensor_reg_bitclear, and status.

Referenced by imu3000_init(), and imu3000_ioctl().

static bool imu3000_get_rotation	(	sensor_hal_t *	hal,
		sensor_data_t *	data
	)

static

Read gyroscope angular rate axis data.

This function reads angular rate data for all 3 axes of an IMU-3000 gyroscope.

Parameters

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

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

References sensor_data_t::axis, sensor_axis_vec_t::axis, IMU3000_GYRO_XOUT_H, sensor_hal::orientation, scale_lsb_per_dps, sensor_data_t::scaled, sensor_bus_read, sensor_fs_sel, sensor_axis_vec_t::sign, sensor_orient_t::x, sensor_orient_t::y, and sensor_orient_t::z.

Referenced by imu3000_ioctl(), and imu3000_read().

static bool imu3000_get_temperature	(	sensor_hal_t *	hal,
		sensor_data_t *	data
	)

static

Read gyroscope integrated temperature sensor data.

This function reads IMU-3000 integrated temperature sensor data. The temperature is always returned in scaled engineering units (degrees Celsius).

Parameters

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

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

References be16_to_cpu, IMU3000_TEMP_OUT_H, sensor_data_t::scaled, sensor_bus_read, TEMP_COUNTS_PER_DEG_C, TEMP_OFFSET, TEMP_REF_DEG, and sensor_data_t::temperature.

Referenced by imu3000_read().

bool imu3000_init	(	sensor_t *	sensor,
		int	resvd
	)

InvenSense IMU-3000 motion processor driver initialization.

This is the main initialization function for the IMU-3000 device.

Parameters

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

Returns: bool true if the sensor is ready for use, else false.

References ARRAYSIZE, sensor_desc::aux, sensor_device_t::func, sensor_desc::hal, imu3000_event(), imu3000_ioctl(), imu3000_read(), sensor_funcs_t::read, SENSOR_CAPS_3_AXIS, SENSOR_CAPS_AUX_ACCEL, SENSOR_CAPS_AUX_TEMP, SENSOR_UNITS_deg_per_sec, SENSOR_VENDOR_INVENSENSE, and status.

static bool imu3000_ioctl	(	sensor_t *	sensor,
		sensor_command_t	cmd,
		void *	arg
	)

static

IMU3000 ioctl control entry point.

This function provides a general-purpose interface for performing various control operations on the sensor device.

Parameters

sensor	Address of an initialized sensor device 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, sensor_desc::err, sensor_desc::hal, imu3000_event(), imu3000_get_rotation(), imu3000_set_bandwidth(), imu3000_set_range(), imu3000_set_sample_rate(), imu3000_set_state(), sensor_data_t::scaled, SENSOR_DISABLE_EVENT, SENSOR_ENABLE_EVENT, SENSOR_ERR_UNSUPPORTED, SENSOR_READ_VECTOR, SENSOR_SET_BANDWIDTH, SENSOR_SET_RANGE, SENSOR_SET_SAMPLE_RATE, SENSOR_SET_STATE, vector3_t::x, vector3_t::y, and vector3_t::z.

Referenced by imu3000_init().

static void imu3000_isr ( volatile void * arg )

static

Invensense IMU3000 driver interrupt service routine.

This is the interrupt service routine for enabled IMU3000 interrupt events. Only the new data ("raw data ready") interrupt is supported.

Parameters

arg	The address of the driver sensor_hal_t descriptor.

Returns: Nothing.

References sensor_event_callback_t::arg, sensor_data_t::axis, sensor_axis_vec_t::axis, sensor_hal::burst_addr, sensor_hal::bus, sensor_event_data_t::data, sensor_event_data_t::event, sensor_event_callback_t::handler, bus_desc_t::no_wait, sensor_hal::orientation, scale_lsb_per_dps, sensor_data_t::scaled, sensor_bus_read, SENSOR_EVENT_NEW_DATA, sensor_fs_sel, sensor_timestamp(), sensor_axis_vec_t::sign, bus_desc_t::status, STATUS_OK, sensor_data_t::timestamp, sensor_orient_t::x, imu3000_event_t::x_hi, imu3000_event_t::x_lo, sensor_orient_t::y, imu3000_event_t::y_hi, imu3000_event_t::y_lo, sensor_orient_t::z, imu3000_event_t::z_hi, and imu3000_event_t::z_lo.

static bool imu3000_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 sensor_desc::err, sensor_desc::hal, imu3000_device_id(), imu3000_get_rotation(), imu3000_get_temperature(), SENSOR_ERR_FUNCTION, SENSOR_READ_ID, SENSOR_READ_ROTATION, and SENSOR_READ_TEMPERATURE.

Referenced by imu3000_init().

static bool imu3000_set_bandwidth	(	sensor_hal_t *	hal,
		int16_t	band
	)

static

Set the IMU-3000 low-pass filter bandwidth.

This routine sets the IMU-3000 low-pass filter bandwidth and the internal sample rate used by the device. This internal sample rate is then further scaled by the sample rate divider (SMPLRT_DIV) value to produce the gyro sample rate according to the formula:

     F_sample = F_internal / (divider + 1)

Valid filter bandwidths and the associated internal sample rate are as follows:

*          Low Pass Filter Bandwidth       Internal Sample Rate
*          ____________________________________________________
*              256Hz                           8kHz
*              188Hz                           1kHz
*              98Hz                            1kHz
*              42Hz                            1kHz
*              20Hz                            1kHz
*              10Hz                            1kHz
*              5Hz                             1kHz
* 

Parameters

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

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

References DLPF_CFG_FIELD, IMU3000_DLPF_FS, sensor_bus_get, sensor_bus_put, and sensor_dlpf_cfg.

Referenced by imu3000_ioctl().

static bool imu3000_set_range	(	sensor_hal_t *	hal,
		int16_t	range
	)

static

Set the IMU-3000 full scale range.

This routine sets the IMU-3000 full scale range using an index to a table of valid ranges: +/-250, +/-500, +/-1000, and +/-2000 deg/sec.

Parameters

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

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

References FS_SEL_FIELD, IMU3000_DLPF_FS, sensor_bus_get, sensor_bus_put, and sensor_fs_sel.

Referenced by imu3000_ioctl().

static bool imu3000_set_sample_rate	(	sensor_hal_t *	hal,
		int16_t	rate
	)

static

Set the IMU3000 sample rate.

This routine sets the externally visible IMU3000 sample rate for the device. This sets a divider that scaled down the internal 1Khz or 8 KHz sample rate to the specified frequency, according to the formula:

*
*          F_sample = F_internal / (divider + 1)
*
* 

The internal sampling rate is 1KHz for all filter bandwidths except 256Hz, which uses an 8KHz internal rate.

Parameters

hal	Address of an initialized sensor device descriptor.
rate	The externally visible sampling rate to be set

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

References sensor_hal::bandwidth, IMU3000_SMPLRT_DIV, and sensor_bus_put.

Referenced by imu3000_ioctl().

static bool imu3000_set_state	(	sensor_hal_t *	hal,
		sensor_state_t	state
	)

static

Set the IMU-3000 execution mode.

This routine sets a specified IMU-3000 execution state to one of the following:

SENSOR_STATE_SLEEP or SENSOR_STATE_LOWEST_POWER Setting the sleep mode puts the device into very low power sleep mode. In this mode, only the serial interface and internal registers remain active.

SENSOR_STATE_NORMAL or SENSOR_STATE_HIGHEST_POWER Sets the device to a normal operational state.

SENSOR_STATE_RESET Sets the device and internal registers to the power-up default settings.

Parameters

sensor	Address of an initialized sensor device descriptor.
state	A specified sensor operational state.

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

Todo:

Update sensor device descriptor operational settings.

References delay_ms, imu3000_default_init(), IMU3000_PWR_MGM, PWR_MGM_SLEEP, sensor_reg_bitclear, sensor_reg_bitset, SENSOR_STATE_HIGHEST_POWER, SENSOR_STATE_LOWEST_POWER, SENSOR_STATE_NORMAL, SENSOR_STATE_RESET, and SENSOR_STATE_SLEEP.

Referenced by imu3000_ioctl().

const sensor_map_t band_table[]

static

Initial value:

= {
    {{  5}, DLPF_CFG_5HZ  }, {{ 10}, DLPF_CFG_10HZ },
    {{ 20}, DLPF_CFG_20HZ }, {{ 42}, DLPF_CFG_42HZ },
    {{ 98}, DLPF_CFG_98HZ }, {{188}, DLPF_CFG_188HZ},
    {{256}, DLPF_CFG_256HZ} 
}

InvenSense IMU-3000 low-pass Bandwidth Table (hertz, register value)

sensor_event_callback_t event_cb = {.handler = default_event_handler}

static

Sensor Event Callback Descriptor.

const sensor_map_t range_table[]

static

Initial value:

= {
    {{ 250}, FS_SEL_250 }, {{ 500}, FS_SEL_500 },
    {{1000}, FS_SEL_1000}, {{2000}, FS_SEL_2000}
}

InvenSense IMU-3000 Range Table (deg/sec, register value)

int16_t const scale_lsb_per_dps[]

Initial value:

= {
    (131 /  1),      
    (655 / 10),      
    (328 / 10),      
    (164 / 10)       
}

Sensitivity Scale Factors.

Referenced by imu3000_get_rotation(), and imu3000_isr().

int sensor_dlpf_cfg = 3

static

The digital low-pass filter table index defaults to 42 Hz.

Referenced by imu3000_default_init(), and imu3000_set_bandwidth().

int sensor_fs_sel = 3

static

The range table index defaults to 2000 deg/sec full-scale.

Referenced by imu3000_default_init(), imu3000_get_rotation(), imu3000_isr(), and imu3000_set_range().

Microchip® Advanced Software Framework

Data Structures

Macros

Functions

Variables