SmartMotion® MEMS Motion Sensors

Hello!

We regularly use the ICM-20948. We find it very helpful, but notice that the timestamps can often be inconsistent or erratic, which is causing problems in our application (high-precision synchronization with a 200 Hz camera).

For example, the sample rate should be 110 Hz according to the documentation, but we find that it fluctuates and can spend significant time sampling at 142 Hz and then it can switch to 83 Hz.

How do I get access to this document? I'm using the ICM-46505 part and have found this document (AN-000364) referenced in both the ICM-45605 datasheet and in the tdk-invn-oss/motion.arduino.ICM45605 Github repo.

Thanks

I am trying to configure ICM-42605 with ESP-WROOM-32 but their is no much resource online.

Thanks in advanced. When I use nrf52832's spi to call "inv_imu_switch_on_mclk" function, I always get MCLK_RDY reg fail. But I can call read_sreg/write_sreg normally. I'm confused for several days. Could anybody help me? Below are my interface:

int inv_io_hal_read_reg(struct inv_imu_serif * serif, uint8_t reg, uint8_t * rbuffer, uint32_t rlen)
{
(void)serif;
uint8_t ul_addr = reg | 0x80;
uint32_t ul_size = rlen + 1;

ZERO_CLEAR(rbuffer);
spi_xfer_done = false;

There is a countpart: RCOSC, but I can't find explanation of WUOSC in datasheet. Could any expert help me？ Thanks.

Hello,

I am trying to connect an Arduino Mega 2560 to a DK-42670-P to read the sensor data using SPI.
Therefore I do not need the Main MCU and debug features of the devkit, I basically just want to use the devkit as a breakout board to connect the sensor to the arduino.

I have connected the 4 SPI wires according to the pin documentation of the boards. I have used the J4 pin which are designated for the SPI interface.

Hi,
I'm interested in using ICM45686 with a magnetometer attached to the AUX interface and I want to be able to access this data inside the FIFO. However, whatever I tried, I couldn't get this to happen. I can get I2CM communication going with the mag, read from it and write values to its registers, but I can't get the data it would return into FIFO. Any pointers?

I got a ICM-42670P, where VDD is connected to a back-up (denoted VDD_BACKUP) supply(3.3V), and VDDIO is connected to a seperate voltage source (denoted VDD3_3V) (3.3V).
I am configuring the IMU to WOM with both voltage sources high, and then i turn off VDD3_3V, because it turns of my MCU. And I was hoping to generate an interrupt (WOM) and use that to re-enable my VDD3_3V. But I am unable to detech any interrupts with VDDIO off? Is that expected?

I try to properly calibrate ICM42605 chip using USER0-USER8 registers.
1. Are stored calibration values internally added to original readings or subtracted from them?
In another words, after reading bias values when device is not in motion do I need to store them in USER0-USER8 registers with the same or with opposite sign?
I was unable to find this info in the datasheet.
2. Does configured calibration data endianness needs to match endianness configured in INTF_CONFIG0 reg?

I want to use the IMU to continuously read accelerometer and gyroscope values while also enabling Freefall and SMD (Significant Motion Detection) interrupts. However, the application note mentions that the power register needs to be set to 0x02 for Freefall and SMD detection, which puts the accelerometer on low power mode and turns off the gyroscope. Is there a way to enable Freefall and SMD detection without switching the power register, or is changing the power register the only option? If there’s an alternative configuration or register setting, please advise.