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IIM42652

This module contains the I2C driver for IIM-42652 6-axis SmartIndustrial™ MotionTracking device that supports an extended operating temperature range. The IIM-42652 combines a 3-axis gyroscope (up to ±2000 degrees/sec), and a 3-axis accelerometer (up to ±16g) and features a 2K-byte FIFO that can lower the traffic on the serial bus interface and reduce power consumption by allowing the system processor to burst read sensor data and then go into a low-power mode.

datasheet

class IIM42652

IIM42652(drv=I2C0, addr=0x68, clk=1000000)
Create an instance of a new IIM-42652 device controlled by I2C.

  • drv is the I2C drive to use. Default is I2C0;
  • addr is the I2C address of the device. Default is 0x68;
  • clk is the I2C clock speed to use. Default is 1000000.

method soft_reset

soft_reset()
Send a soft reset command to the IIM-42652. This will set all the device registers to the default values.

method set_drive

set_drive(i2c_sr)
Set the desired slew rate for the IIM-42652's I2C. For additional information, see register DRIVE_CONFIG on IIM-42652 datasheet.

  • i2c_sr is the desired I2C slew rate.

method setup

setup()
Automatically configure the device to work in I2C mode.

method get_temp

get_temp()
Returns the temperature value [°C] read form the temperature sensor onboard IIM-42652.

method get_accel_x

get_accel_x()
Returns the last read acceleration value on x axis.

method get_accel_y

get_accel_y()
Returns the last read acceleration value on y axis.

method get_accel_z

get_accel_z()
Returns the last read acceleration value on z axis.

method get_gyro_x

get_gyro_x()
Returns the last read gyroscope value on x axis.

method get_gyro_y

get_gyro_x()
Returns the last read gyroscope value on y axis.

method get_gyro_z

get_gyro_x()
Returns the last read gyroscope value on z axis.

method set_pwr_cfg

set_pwr_cfg(acc, gyro, idle=0, tmp=0)
Set the power configuration of the device. This is required to power up gyroscope and accelerometer. For additional information, see register PWR_MGMT0 on IIM-42652 datasheet.

  • acc is the accelerometer power configuration. Reset value is 0b00.

    acc Mode
    0b00 Off
    0b01 Off
    0b10 Low Power
    0b11 Low Noise
  • gyro is the gyroscope power configuration. Reset value is 0b00.

    gyro Mode
    0b00 Off
    0b01 Off
    0b10 Low Power
    0b11 Low Noise
  • idle set to 1 to keep the RC Oscillator always on. Default value is 0, reset value is 0.

  • tmp_dis set to 1 to disable the temperature sensor. Default value is 0, reset value is 0.

method set_accel_cfg

set_accel_cfg(odr, fs)
Set the accelerometer configuration for Output Data Rate and Full Scale. For additional information, see register ACCEL_CONFIG0 on IIM-42652 datasheet.

  • odr is the Output Data Rate. Reset value is 0b0110 (32 kHz).

  • fs is the Full Scale. Reset value is 0b000 (±16 g).

method set_gyro_cfg

set_gyro_cfg(odr, fs)
Set the gyroscope configuration for Output Data Rate and Full Scale. For additional information, see register GYRO_CONFIG0 on IIM-42652 datasheet.

  • odr is the Output Data Rate. Reset value is 0b0110 (32 kHz).

  • fs is the Full Scale. Reset value is 0b000 (±2000 degrees/sec).

method set_fifo_cfg

set_fifo_cfg(accel_en, gyro_en, tmp_en=False, tmst_en=False, hires_en=False, wm_gt_th=False, res_rd=False)
Set the fifo configuration to select data saved on the fifo. For additional information, see register FIFO_CONFIG1 on IIM-42652 datasheet.

  • accel_en if set to True allows accelerations data of the 3-axis to go to the fifo.

  • gyro_en if set to True allows gyro data of the 3-axis to go to the fifo.

  • tmp_en if set to True allows temperature data to go to the fifo. Default False.

  • tmst_en if set to True allows time stamp data to go to the fifo. Default False.

  • hires_en if set to True enable the high resolutions data on the fifo. Default False.

  • wm_gt_th if set to True enables fifo watermark on every ODR if data on fifo are over watermark. Default False.

  • res_rd if set to True allows partial read from the fifo. Reading again will resume from the last byte read. Default False

method fifo_cnt

fifo_cnt()
Get the current number of bytes stored on the fifo.

method set_fifo_mode

set_fifo_mode(mode)
Set the mode used by the fifo. For additional information, see register FIFO_CONFIG on IIM-42652 datasheet.

  • mode is the mode of the fifo. Reset value is 0b00.

    mode Mode
    0b00 Bypass
    0b01 Stream-to-FIFO
    0b10 STOP-on-FULL
    0b11 STOP-on-FULL

method handle_fifo

handle_fifo(buf)
Return a tuple with a packet of measures elaborated from the full fifo buffer. The first byte passed should be the header of the packet. The first value of the returned tuple is the number of bytes used to create the packet.

  • buf is the buffer to get the first packet from.

Return a tuple with the following fromat. ( n_bytes, header, measure_1, measure_2, ..., measure_n)

  • n_bytes number of bytes that contained the packet.

  • header is the header of the packet.

  • measure_# are the measures, depending on the fifo configuration.

method set_fsync_cfg

set_fsync_cfg(pol, ui_clear_flag, ui)
Set the fsync configuration. For additional information, see register FSYNC_CONFIG on IIM-42652 datasheet.

  • pol is the polarity of the fsync pulse.

  • ui_clear_flag if set to 1 fysnc flag is cleared when ui sensor register is updated.

  • ui select the fysnc flag tag.

method get_fifo

get_fifo(n)
Get n bytes from the fifo.

  • n is the number of bytes to get from the fifo.

Returns a bytearray with n bytes.

set_signal_path

set_signal_path(fifo_flush, tmst_strobe, abort_n_reset, dmp_mem_rst=False, dmp_init_en=False)
Set the signal path reset. For additional information, see register SIGNAL_PATH_RESET on IIM-42652 datasheet.

  • fifo_flush if set to True the fifo is flushed.

  • tmst_strobe if set to True time stamp counter is latched into time stamp register.

  • abort_n_reset if set to True signal path is reset an ODR restarted.

  • dmp_mem_rst if set to True the DMP memory is reset. Default False.

  • dmp_init_en if set to True the DMP memory is enabled. Default False.

method set_fifo_decimation

set_fifo_decimation(dec)
Set the decimation of data stored on the fifo. If decimation is 5 only one data over 5 will be stored on the fifo.

  • dec is the decimation to set. Range 0-127.

method set_fifo_wm

set_fifo_wm(wm)
Set the fifo watermark. If fifo counter is higher than the watermark an interrupt can be generated.

  • wm is the watermark value to set.

method set_int_cfg

set_int_cfg(int_pin, mode, drive, polarity)
Set the interrupt pin configuration. For additional information, see register INT_CONFIG on IIM-42652 datasheet.

  • int_pinis the pin of IIM42652 to configure.

  • mode is the mode of the interrupt. 0 for pulsed, 1 for latched.

  • drive is the drive configuration. 0 open drain, 1 push pull.

  • polarity is the polarity of the pin. 0 active low, 1 active high.

method set_int_sources

set_int_sources(int_pin, fifo_full, fifo_ths, ui_acg_rdy=False, ui_drdy=False, reset_done=False, pll_rdy=False, ui_fsync=False)
Set sources that can trigger an interrupt on a pin. For additional information, see register INT_SOURCE0 on IIM-42652 datasheet.

  • int_pin is the pin of IIM42652 to configure.

  • fifo_full if set to True interrupt is triggered when fifo is full.

  • fifo_ths if set to True interrupt is triggered when fifo watermark is reached. Default False.

  • ui_acg_rdy if set to True interrupt is triggered if UI AGC is ready. Default False.

  • ui_drdy if set to True interrupt is triggered if UI data are ready. Default False.

  • reset_done if set to True interrupt is triggered if reset is completed. Default False.

  • pll_rdy if set to True interrupt is triggered if PLL is ready. Default False.

  • ui_fsync if set to True interrupt is triggered if UI fsync is triggered. Default False.

method get_int_status

get_int_status()
Returns the interrupt register status. The register tells what triggered the interrupt. For additional information, see register INT_STATUS on IIM-42652 datasheet.

method set_int_clear_cfg

set_int_clear_cfg(fifo_full, fifo_ths, ui_drdy)
Set the method to clear interrupt.

val clear method
0b00 Status bit read
0b01 Status bit read
0b10 Sensor reg read
0b11 Both above methods

For additional information, see register INT_CONFIG0 on IIM-42652 datasheet.

  • fifo_full is the clear method of fifo full interrupt.

  • fifo_ths is the clear method of fifo watermark threshold interrupt.

  • ui_drdy is the clear method of ui data ready interrupt.

Example

from bsp import board
from components.iim42652 import iim42652
# Create a iim42652 class with i2c
iim = iim42652.IIM42652()
sleep(500)
# Software reset of the iim42652
iim.soft_reset()
# Set up the device for I2C communication
iim.setup()
# Set accel and config
# Accel ODR = 2khz, full scale = 16 g
iim.set_accel_cfg(0b0101, 0b000)
# Set fifo in stream mode
iim.set_fifo_mode(0b01)
# Power accels and gyros on low noise mode
iim.set_pwr_cfg(3, 0, 0, 0)
while True:
    sleep(1000)
    print("accel x:", iim.get_accel_x())
    print("accel y:", iim.get_accel_y())
    print("accel z:", iim.get_accel_z())