ICM20648 - Motion Sensor#

Driver for the Invensense ICM20648 6-axis motion sensor.

Modules#

Register definitions

Functions#

sl_status_t

Initialize the SPI bus to communicate with the ICM20648.

void
sl_icm20648_read_register(uint16_t addr, int numBytes, uint8_t *data)

Read register from the ICM20648 device.

void
sl_icm20648_write_register(uint16_t addr, uint8_t data)

Write a register in the ICM20648 device.

void

Select the desired register bank.

sl_status_t

Perform soft reset on the ICM20648 chip.

sl_status_t
sl_icm20648_set_sample_rate(float sampleRate)

Set the sample rate both of the accelerometer and the gyroscope.

float

Set the sample rate of the accelerometer.

float

Set the sample rate of the gyroscope.

sl_status_t

Set the bandwidth of the gyroscope.

sl_status_t

Set the bandwidth of the accelerometer.

sl_status_t

Read the raw acceleration value and convert to g value based on the actual resolution.

sl_status_t

Read the raw gyroscope value and convert to deg/sec value based on the actual resolution.

sl_status_t

Get the actual resolution of the accelerometer.

sl_status_t

Get the actual resolution of the gyroscope.

sl_status_t

Set the full scale value of the accelerometer.

sl_status_t

Set the full scale value of the gyroscope.

sl_status_t

Enable or disable the sleep mode of the device.

sl_status_t

Enable or disable the cycle mode operation of the accel and gyro.

sl_status_t
sl_icm20648_enable_sensor(bool accel, bool gyro, bool temp)

Enable or disable the sensors in the ICM20648 chip.

sl_status_t
sl_icm20648_enter_low_power_mode(bool enAccel, bool enGyro, bool enTemp)

Enable or disable sensors in low-power mode in the ICM20648 chip.

sl_status_t
sl_icm20648_enable_interrupt(bool dataReadyEnable, bool womEnable)

Enable or disable the interrupts in the ICM20648 chip.

sl_status_t
sl_icm20648_read_interrupt_status(uint32_t *int_status)

Read the interrupt status registers of the ICM20648 chip.

bool

Check if new data is available to read.

sl_status_t
sl_icm20648_enable_wake_on_motion_interrupt(bool enable, uint8_t womThreshold, float sampleRate)

Set up and enable the Wake-up On Motion feature.

sl_status_t

Initialize the ICM20648 sensor.

sl_status_t

De-initialize the ICM20648 sensor by disconnecting the supply and SPI lines.

sl_status_t
sl_icm20648_calibrate_accel_and_gyro(float *accelBiasScaled, float *gyroBiasScaled)

Accelerometer and gyroscope calibration function.

sl_status_t
sl_icm20648_calibrate_gyro(float *gyroBiasScaled)

Gyroscope calibration function.

sl_status_t

Read the temperature sensor raw value and convert to Celsius.

sl_status_t

Read the device ID of the ICM20648.

Function Documentation#

sl_icm20648_spi_init#

sl_status_t sl_icm20648_spi_init (void )

Initialize the SPI bus to communicate with the ICM20648.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_read_register#

void sl_icm20648_read_register (uint16_t addr, int numBytes, uint8_t * data)

Read register from the ICM20648 device.

Parameters
TypeDirectionArgument NameDescription
uint16_t[in]addr

The register address to read from in the sensor Bit[8:7] - bank address Bit[6:0] - register address

int[in]numBytes

The number of bytes to read

uint8_t *[out]data

The data read from the register


sl_icm20648_write_register#

void sl_icm20648_write_register (uint16_t addr, uint8_t data)

Write a register in the ICM20648 device.

Parameters
TypeDirectionArgument NameDescription
uint16_t[in]addr

The register address to write Bit[8:7] - bank address Bit[6:0] - register address

uint8_t[in]data

The data to write to the register


sl_icm20648_select_register_bank#

void sl_icm20648_select_register_bank (uint8_t bank)

Select the desired register bank.

Parameters
TypeDirectionArgument NameDescription
uint8_t[in]bank

The address of the register bank (0..3)


sl_icm20648_reset#

sl_status_t sl_icm20648_reset (void )

Perform soft reset on the ICM20648 chip.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_set_sample_rate#

sl_status_t sl_icm20648_set_sample_rate (float sampleRate)

Set the sample rate both of the accelerometer and the gyroscope.

Parameters
TypeDirectionArgument NameDescription
float[in]sampleRate

The desired sample rate in Hz. Because the resolution of the sample rate divider is different in the accel and gyro stages, two sensors may have a different sample rate set.

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_gyro_set_sample_rate#

float sl_icm20648_gyro_set_sample_rate (float sampleRate)

Set the sample rate of the accelerometer.

Parameters
TypeDirectionArgument NameDescription
float[in]sampleRate

The desired sample rate in Hz

Returns

  • The actual sample rate, which may be different than the desired value because of the finite and discrete number of divider settings.


sl_icm20648_accel_set_sample_rate#

float sl_icm20648_accel_set_sample_rate (float sampleRate)

Set the sample rate of the gyroscope.

Parameters
TypeDirectionArgument NameDescription
float[in]sampleRate

The desired sample rate in Hz

Returns

  • The actual sample rate, which may be different than the desired value because of the finite and discrete number of divider settings.


sl_icm20648_gyro_set_bandwidth#

sl_status_t sl_icm20648_gyro_set_bandwidth (uint8_t gyroBw)

Set the bandwidth of the gyroscope.

Parameters
TypeDirectionArgument NameDescription
uint8_t[in]gyroBw

The desired bandwidth value. Use the ICM20648_GYRO_BW_xHZ macros, which are defined in the icm20648.h file. The value of x can be 6, 12, 24, 51, 120, 150, 200, 360 or 12100.

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_accel_set_bandwidth#

sl_status_t sl_icm20648_accel_set_bandwidth (uint8_t accelBw)

Set the bandwidth of the accelerometer.

Parameters
TypeDirectionArgument NameDescription
uint8_t[in]accelBw

The desired bandwidth value. Use the ICM20648_ACCEL_BW_yHZ macros, which are defined in the icm20648.h file. The value of y can be 6, 12, 24, 50, 111, 246, 470 or 1210.

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_accel_read_data#

sl_status_t sl_icm20648_accel_read_data (float * accel)

Read the raw acceleration value and convert to g value based on the actual resolution.

Parameters
TypeDirectionArgument NameDescription
float *[out]accel

A 3-element array of float numbers containing the acceleration values for the x, y and z axes in g units.

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_gyro_read_data#

sl_status_t sl_icm20648_gyro_read_data (float * gyro)

Read the raw gyroscope value and convert to deg/sec value based on the actual resolution.

Parameters
TypeDirectionArgument NameDescription
float *[out]gyro

A 3-element array of float numbers containing the gyroscope values for the x, y and z axes in deg/sec units.

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_accel_get_resolution#

sl_status_t sl_icm20648_accel_get_resolution (float * accelRes)

Get the actual resolution of the accelerometer.

Parameters
TypeDirectionArgument NameDescription
float *[out]accelRes

The resolution in g/bit units

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_gyro_get_resolution#

sl_status_t sl_icm20648_gyro_get_resolution (float * gyroRes)

Get the actual resolution of the gyroscope.

Parameters
TypeDirectionArgument NameDescription
float *[out]gyroRes

The actual resolution in (deg/sec)/bit units

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_accel_set_full_scale#

sl_status_t sl_icm20648_accel_set_full_scale (uint8_t accelFs)

Set the full scale value of the accelerometer.

Parameters
TypeDirectionArgument NameDescription
uint8_t[in]accelFs

The desired full scale value. Use the ICM20648_ACCEL_FULLSCALE_xG macros, which are defined in the icm20648.h file. The value of x can be 2, 4, 8 or 16.

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_gyro_set_full_scale#

sl_status_t sl_icm20648_gyro_set_full_scale (uint8_t gyroFs)

Set the full scale value of the gyroscope.

Parameters
TypeDirectionArgument NameDescription
uint8_t[in]gyroFs

The desired full scale value. Use the ICM20648_GYRO_FULLSCALE_yDPS macros, which are defined in the icm20648.h file. The value of y can be 250, 500, 1000 or 2000.

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_enable_sleep_mode#

sl_status_t sl_icm20648_enable_sleep_mode (bool enable)

Enable or disable the sleep mode of the device.

Parameters
TypeDirectionArgument NameDescription
bool[in]enable

If true, sleep mode is enabled. Set to false to disable sleep mode.

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_enable_cycle_mode#

sl_status_t sl_icm20648_enable_cycle_mode (bool enable)

Enable or disable the cycle mode operation of the accel and gyro.

Parameters
TypeDirectionArgument NameDescription
bool[in]enable

If true both the accel and gyro sensors will operate in cycle mode. If false the senors working in continuous mode.

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_enable_sensor#

sl_status_t sl_icm20648_enable_sensor (bool accel, bool gyro, bool temp)

Enable or disable the sensors in the ICM20648 chip.

Parameters
TypeDirectionArgument NameDescription
bool[in]accel

If true, enables the acceleration sensor

bool[in]gyro

If true, enables the gyroscope sensor

bool[in]temp

If true, enables the temperature sensor

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_enter_low_power_mode#

sl_status_t sl_icm20648_enter_low_power_mode (bool enAccel, bool enGyro, bool enTemp)

Enable or disable sensors in low-power mode in the ICM20648 chip.

Parameters
TypeDirectionArgument NameDescription
bool[in]enAccel

If true, enables the acceleration sensor in low power mode

bool[in]enGyro

If true, enables the gyroscope sensor in low power mode

bool[in]enTemp

If true, enables the temperature sensor in low power mode

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_enable_interrupt#

sl_status_t sl_icm20648_enable_interrupt (bool dataReadyEnable, bool womEnable)

Enable or disable the interrupts in the ICM20648 chip.

Parameters
TypeDirectionArgument NameDescription
bool[in]dataReadyEnable

If true, enables the Raw Data Ready interrupt, otherwise disables.

bool[in]womEnable

If true, enables the Wake-up On Motion interrupt, otherwise disables.

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_read_interrupt_status#

sl_status_t sl_icm20648_read_interrupt_status (uint32_t * int_status)

Read the interrupt status registers of the ICM20648 chip.

Parameters
TypeDirectionArgument NameDescription
uint32_t *[out]int_status

The content the four interrupt registers. LSByte is INT_STATUS, MSByte is INT_STATUS_3

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_is_data_ready#

bool sl_icm20648_is_data_ready (void )

Check if new data is available to read.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Returns

  • Returns true if the Raw Data Ready interrupt bit set, false otherwise


sl_icm20648_enable_wake_on_motion_interrupt#

sl_status_t sl_icm20648_enable_wake_on_motion_interrupt (bool enable, uint8_t womThreshold, float sampleRate)

Set up and enable the Wake-up On Motion feature.

Parameters
TypeDirectionArgument NameDescription
bool[in]enable

If true enables the WOM feature, disables otherwise

uint8_t[in]womThreshold

Threshold value for the Wake on Motion Interrupt for ACCEL x/y/z axes. LSB = 4mg. Range is 0mg to 1020mg

float[in]sampleRate

The desired sample rate of the accel sensor in Hz

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_init#

sl_status_t sl_icm20648_init (void )

Initialize the ICM20648 sensor.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Enable the power supply and SPI lines, set up the host SPI controller, configure the chip control interface, clock generator, and interrupt line.

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_deinit#

sl_status_t sl_icm20648_deinit (void )

De-initialize the ICM20648 sensor by disconnecting the supply and SPI lines.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_calibrate_accel_and_gyro#

sl_status_t sl_icm20648_calibrate_accel_and_gyro (float * accelBiasScaled, float * gyroBiasScaled)

Accelerometer and gyroscope calibration function.

Parameters
TypeDirectionArgument NameDescription
float *[out]accelBiasScaled

The mesured acceleration sensor bias in mg

float *[out]gyroBiasScaled

The mesured gyro sensor bias in deg/sec

Reads the gyroscope and accelerometer values while the device is at rest and in level. The resulting values are loaded to the accel and gyro bias registers to cancel the static offset error.

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_calibrate_gyro#

sl_status_t sl_icm20648_calibrate_gyro (float * gyroBiasScaled)

Gyroscope calibration function.

Parameters
TypeDirectionArgument NameDescription
float *[out]gyroBiasScaled

The mesured gyro sensor bias in deg/sec

Read the gyroscope values while the device is at rest and in level. The resulting values are loaded to the gyro bias registers to cancel the static offset error.

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_read_temperature_data#

sl_status_t sl_icm20648_read_temperature_data (float * temperature)

Read the temperature sensor raw value and convert to Celsius.

Parameters
TypeDirectionArgument NameDescription
float *[out]temperature

The mesured temperature in Celsius

Returns

  • Returns zero on OK, non-zero otherwise


sl_icm20648_get_device_id#

sl_status_t sl_icm20648_get_device_id (uint8_t * devID)

Read the device ID of the ICM20648.

Parameters
TypeDirectionArgument NameDescription
uint8_t *[out]devID

The ID of the device read from the WHO_AM_I register. Expected value 0xE0.

Returns

  • Returns zero on OK, non-zero otherwise