MEMS (sensors)

Hello. I have LIS2DUX12 accelerometer and have sucessfully ran machine learning example from STMems (activity_recognition_for_mobile) on our custom hardware.https://github.com/STMicroelectronics/STMems_Standard_C_drivers/blob/master/lis2dux12_STdC/examples/lis2dux12_mlc_activity_mobile.cFor our application, we need to be able to reliably detect when our device is being transported with a car but its not so straightforward. The few difficulties include:1. The device orientation is not fixed2. The device may shake gently or move very slowly during its normal application. This is perfectly fine and we should somehow not detect that. I have looked at different application_examples :https://github.com/STMicroelectronics/STMems_Machine_Learning_Core/tree/master/application_examplesbut not sure which would work best for us. If we cant find any suitable application example, we can try and train our own model with our own data.I would appreciate if someone could share their insights and pr

Hello,We have the ISM330DHCX designed into a new product but I am having trouble getting reliable readings using the I2C interface. I am able to read the WHOAMI register and get 0x6B but OUT_TEMP_L (20h), OUT_TEMP_H (21h) always return zero.I have the interface instrumented and I can see that the signalling is correct, with repeated start and everything, but only zeros.Does anyone have a suggestion of how this is happening?  Do I need to do something special to enable temperature readings?Thanks

 Hi everyone,I am working with the  LSM6DSM and an external LIS3MDL magnetometer and have the FIFO ODR set to 208 Hz, with no decimation configured.I am trying to understand exactly how the FIFO handles data in the following four scenarios. Could someone clarify what happens to the samples in the FIFO for each case?The Accelerometer or Gyroscope ODR is set higher than 208 Hz.The Accelerometer or Gyroscope ODR is set lower than 208 Hz.The external Magnetometer ODR is set higher than 208 Hz.The external Magnetometer ODR is set lower than 208 Hz.Any clear explanations on how the samples are handled (e.g., are they dropped, duplicated?) in these specific situations would be greatly appreciated.Thanks!

While using the iis3dw sensor, I discovered that when I employed an interrupt-based polling method to read data—where, ideally, the sensor captures data, triggers an interrupt, and then the data is read—the data acquisition frequency should be around 26 kHz (based on SPI transmission and code execution time). However, I found that reading the data was taking up some of that time; when I disabled this process, the issue disappeared. My SPI rate is 18 Mbps. Subsequent testing with FIFO reading also exhibited this behavior. Specifically, when I disabled the function `iis3dwb_acceleration_raw_get(&IIS3DWB_ctx, accel)` during the read process, reading 10,240 data points took approximately 391 ms (about 26k). Without disabling it, reading the same 10,240 data points took 523 ms (about 19k). Below is my read code without using FIFO. The attachment contains the official ST driver. `uint8_t iis3dwb_init_drdy_mode(void)` is the initialization function without using FIFO, int16_t iis3dwb_read

Split from Any accelerometer supporting >400g with integrated free-fall detection ? - this is a separate questionHi Team,Could you please suggest a suitable wireless development board that supports LSM6DSV320X, or any latest high g accelerometer sensors, apart from Sensor Tile Box Pro?

I am working with the LSM6DSV320X for vibration analysis and potential crash detection applications, and I have a few questions regarding its capabilities and system integration:Is the LSM6DSV320X considered a high-end processing device? Does it support on-board processing such as FFT, or is an external MCU required for such computations?What are the maximum bandwidth and measurement ranges (g for accelerometer and dps for gyroscope) available for the 6-axis IMU? How suitable are these for high-frequency vibration or crash event detection?How fast is the communication interface (I2C/SPI)? Can it reliably support high data rate streaming for real-time applications?Is it possible to integrate this sensor directly with a CAN bus, or is an external microcontroller required for CAN communication?Are there any development boards available that include this sensor for quick evaluation and prototyping?I would appreciate guidance or references to relevant documentation.

In LSM6DSV16X DS13510-Rev 4 Page 8, Table lists sensor fusion performance: Question 1: are these values guaranteed over temperature and all angles, or at a particular angle and at room temperature?Question 2: without a magnetometer or GNSS heading input, what is meant by heading/yaw accuracy? Is it a drift value (over 5 minutes) from whatever value it is given at the beginning of 5 minutes?Thank you.

Many years ago, at ANU in third year physics, the professor provided an object and said explain and check it as a project.  Let us assume that I have a SENSOR TILE.BOX pro and I follow my training and check the output of the MEMS Studio. The first step was to provide the CLI_Example amended so that it provided the files in the correct location for our downstream software.  I would not use your MEMs software, it is just to kludgy.  But I wanted to confirm my program and understand your data.The next step is to use MEMS Studio to get the output file processed log. The third step is to write a simple C# program to take the .dat files apart and complete necessary analysis and upload the needed output to the MYSQL cloud storage. {"c_type": 2,"data_ext": ".dat","data_fmt": "HSD_2.0.0","description": "","end_time": "2026-04-02T17:48:41.013Z","interface": 1,"name": "SensorTile.Box_PRO_acquisition","schema_version": "2.0.0","start_time": "2026-04-02T17:48:30.000Z","tags

It appears that the longest spi operation that could be used to access the LSM6DSV (and related parts) would read a single fifo entry (7 bytes) and it is not possible to read all the available fifo entries in a single dma operation.  Am I missing something? Geoffrey

Hi, ST Community, I am working with an lis2mdl on a STEVAL-MKI217V1 board and I used lis2mdl_hard_iron.c this Application and I was able to get data_raw_magnetic and magnetic_mG I want API to get the Angle of Rotation of the sensor  

Hello,I am testing LSM6DSO and LSM6DSO32 on Zephyr.As these 2 sensors are pin compatible, I prepared 2 identical boards, one is mounted with LSM6DSO and LSM6DSO32 on another. (The sensors are connected to MCU through SPI interface.)My purpose is that I can use one single Zephyr image to drive the IMU sensor no matter which one of these 2 sensors is mounted on board.It looks promising because one lsm6dso.c driver is provided in Zephyr, and this driver defined DT_DRV_COMPAT for LSM6DSO32. And Zephyr's official document also confirmed this compatible as well.So I use the default sample/sensor/lsm6dso app for a simple testing.The sample can be built and run for the board with LSM6DSO. The output from the uart console looks making sense.But I encountered some problems when configure the dts file for the board with LSM6DSO32.At first I config the dts file like this:lsm6dso: lsm6dso@0 { compatible = "st,lsm6dso32", "st,lsm6dso"; ... }This can not compile, the c

Hi, I am looking for the burn-in specifications for a MEMS accelerometer device/sensor. Could you please help me with this information? Thank you

Hi Team, do ST offer a high-g accelerometer, similar to the LSM6DSV320X on the STEVAL-MKI251A, that supports over 400g with integrated free-fall detection?

I am using the STEVAL-MKI238A kit with the LIS2DUX12 chip. This is connected to an NRF52840DK and interfaced using Zephyr's lis2dux12 driver. The eval kit is connected to the SPI3 device using its default settings. I am running an SPI clock of 1Mhz and the VDD and VDIO pins are supplied 1.85V+GND from a shared power supply with the nrf52840dk. The Zephyr lis2dux12 driver is hard coded to use SPI mode 3, so CPOL+CPHA.The lis2dux12 driver fails its INIT sequence by mismatch of the WHO_AM_I readback. The device seemingly returns 0x0C.I have connected a logic analyzer to the pins of the eval kit shows this sequence:- 0x01 is written to register 0x3E to wake the device up from sleep- Once the CS signal is disabled, 50ms passes before the next CS enable to allow the sensor to wake up- A read request is made to register 0x8F (bit 7 read + 0x0F)- The clock idles for 48.5µs before pulsing for the response- The sensor effectively pulses 0000.1100b- However the sensor seems to attempt to set

I notice there is now a github repo with FSM examples; very useful!However, in comparing what I have been successfully using, for example, for shake detection on the LSM6DSV (or LSM6DSV80X) where 30 lines are written to page 0x7A: _i2c_bus->writeByte(i2cAddress, LSM6DSV80X_PAGE_VALUE, 0xC0 | 0x20 | 0x02); // write to CONFIG_A (three thresholds, two masks, two short timers) _i2c_bus->writeByte(i2cAddress, LSM6DSV80X_PAGE_VALUE, 0x00); // write to CONFIG_B _i2c_bus->writeByte(i2cAddress, LSM6DSV80X_PAGE_VALUE, 0x1E); // write to SIZE (30 byte program) _i2c_bus->writeByte(i2cAddress, LSM6DSV80X_PAGE_VALUE, 0x00); // write to SETTINGS _i2c_bus->writeByte(i2cAddress, LSM6DSV80X_PAGE_VALUE, 0x00); // write to RESET POINTER _i2c_bus->writeByte(i2cAddress, LSM6DSV80X_PAGE_VALUE, 0x00); // write to PROGRAM POINTER _i2c_bus->writeByte(i2cAddress, LSM6DSV80X_PAGE_VALUE, 0x66); // write to THRESH1 LSB _i2c_bus->writeByte(i2cAddress, LSM6DSV80X_PAGE_VALUE, 0x3E); // w

I'm stuck at trying to make motion_fx call MotionFX_LoadMagCalFromNVM and MotionFX_SaveMagCalInNVM - a problem which is mentioned already in link1 and link2 but to which actually there is no working solution (the rest of the motion_fx seems to work without any issue). I implemented the functions as below, but already when compiling, they get optimised out and end up being discarded - hence the motion_fx library never calls them, in contrary to what UM2220 suggests. My code does actively call MotionFX_MagCal_init(MFX_MAGCAL_SAMPLE_PERIOD_MS, 1); and MotionFX_MagCal_init(MFX_MAGCAL_SAMPLE_PERIOD_MS, 0); which as per UM2220 should trigger the call of the NVM functions. Here is my implementation:volatile int deb_load_nvm_called = 0; volatile int deb_save_nvm_called = 0; char MotionFX_LoadMagCalFromNVM(unsigned short int dataSize, unsigned int *data) { Message_Logger("hi from save %i", deb_load_nvm_called); deb_load_nvm_called++; nvm_status_t s = NVM

In the getting started guide there is a programmable audio buzzer names SPK1 but I can't find reference of it anywhere, where I can enable it in the .ioc file and how to interact with it? Please could someone advise me on this.

Hi, ST Community, I am working with an LSM6DSOX on a custom board, using an ESP32S3 with the Arduino framework, and I'm unable to get the Machine Learning Core (MLC) to run.The problem is that the output register MLC0_SRC (0x70) always reads 0x00. I am also monitoring the is_mlc_ok status bit in the EMB_FUNC_STATUS register (0x15), and it never gets set to 1. Basic communication (reading WHO_AM_I and raw accelerometer data) works perfectly.I am not using a library and am writing directly to the registers. My initialization sequence is as follows:Software Reset: Write 0x01 to CTRL3_C (0x12).Wait: A 100ms delay to ensure the reset is complete.Enable Embedded Functions Access: Write 0x80 to FUNC_CFG_ACCESS (0x01).Load UCF Data: Write the entire .ucf file (288 bytes) byte-by-byte by setting the address in MLC_A_ADD (0x02) and writing the data to MLC_B_ADD (0x03). I have verified the data is being written.Disable Embedded Functions Access: Write 0x00 to FUNC_CFG_ACCESS (0x01).Enable ML

The sensor box pro is a neat device.  If I use the CLI Example program and the USB cable, I can get 8000 data points per second, if I use a traditional C# program I get 8 data points per second.  The CLI yields dat files, which can be read with a simple C# program, although why you would mix 6 and 4 data groups is beyond my skill set to understand, but it is easier to use than Python and MEMS Set.   And it is easier to do the byte data in C#.  (It took less time to write this program than I spent trying to get Python to work.)CLI Example makes me type enter to start.  I have many ST.COM accelerometers all over the world and I am not going to type enter to start, but the main.cpp and main.h and the cmake lists file will not compile in CMAKE or Visual Studio.  So I cannot fix the challenging feature. Could we get VS SLNX file and the C++ code for this program as part of the SLNX so it is easy to take out the enter statement and break the outpu

Hello, I have a setup with a processing unit connected to two IMU sensors via SPI.One of those IMU's is the IIS3DWB.I am configuring the IIS3DWB with FIFO in continuous mode and I can read data properly from FIFO.I decided to make long run tests. With these tests, I noticed that some times after 10 minutes, after 2h or more, I can't read data from the IIS3DWB FIFO since the values read from FIFO_STATUS1 and FIFO_STATUS2 are 0.I wrote a piece of code to only run after this transition from proper read to read 0's, where I read the CHIP_ID and the FIFO_CTRL registers. The result is a proper read of the CHIP_ID and the all FIFO_CTRL registers are read as 0.It looks to me that some reset occurred to the internal registers. Aren't the capacitors of the STEVAL board making his job?As a note, the other IMU continuous working properly and SPI bus also does not present any issue.Do you have a suggestion on how to mitigate or debug further?Thank you. 

Hello,I am currently working on a drone project based on the STEVAL-FCU001V2 board. My hardware setup consists of:Motors: 4x 8520 Coreless DC motors (3.7V).Battery: 1S LiPo 600mAh (30C).Frame: Custom micro-drone frame (~60g AUW).I am looking for a reliable and fully functional firmware (source code or .bin) that is compatible with the latest mobile application for flight control of STM.I’ve noticed that the original ST Drone (or ST BLE Drone) application sometimes has connectivity or stability issues with recent Android/iOS versions.My questions are:Is there a specific version of the STSW-FCU001 firmware that you recommend for best stability in 2026?Is the "ST Drone" app still the official way to fly this board via BLE, or is there a community fork or a newer ST app recommended for this specific FCU?Are there any known patches for the PID values or PWM frequency (specifically for 8520 motors) to improve the hover stability?Any advice, GitHub links, or updated STSW packages would be gre

 Dear all,I am struggling with getting a good SFLP result, that does not drift too much and does not appear jittery. I went trough most of the posts here but I am still not able to get good results (approx. factor 10 higher drift then according to the data sheet). in one of the posts I found the explanation about the chain of the SPFL:  that was the one im ent: For now, you have the answers: SFLP (as MLC/FSM and other embedded functions) take its input from LPF1 in the accelerometer chain, and from LPF2 in the gyroscope chain; their setting will therefore impact SFLP. Higher ODR leads to a more accurate gyroscope integration, but sensor RMS noise will also be higher. Gyroscope saturation should be avoided, accelerometer saturation matters less. Lower full scale will increase the resolution and therefore the accuracy, but the risk of saturation will be higher. It is a delicate balance that is specific to every application. Post in forum According to th

We are currently experiencing issues with the LPS28DFW.We observe pressure values dropping to 0 or even negative ranges (e.g., around -400 mPa), as well as unexpectedly high values (up to approximately 1200 mPa), while the expected range should be around 950 mPa. We are also seeing abnormal temperature outputs, including unrealistically low values (e.g., around -400°C).this happens when the sensor is in contact only with air and also when it is in contact only with water. When the sensors from the field they are brought back in the lab the sensors seem to recover on their own and return to normal readings.

Hi,I'm using the LIS2DUXS12 in FIFO Stream mode with DEC_TS_32. FIFO watermark is set to 64. Looks like every ~17 FIFO reads (~1055 XL samples), exactly 1 accelerometer sample is lost. The pattern is consistent and repeatable.Each FIFO read of 64 entries normally contains 62 XL samples + 2 timestamp tags. However, every 17th read contains 63 XL + 1 timestamp tag. Looks like before this batch with 63 XL samples, there is 1 XL sample gap in data.I use only the timestamp present in the FIFO batch to calculate timestamp for each sample. And with that approach samples in that FIFO batch aligns with next FIFO batch exactly - no gaps, no overwriting, fixed period. So despite the fact that this FIFO batch contains one XL sample more than the other, there's still a gap in data. Configuration:- ODR: 200 Hz (HP mode)- FIFO mode: Stream (continuous)- bdr_xl: ODR- dec_ts: DEC_TS_32- xl_only_fifo: 1- FIFO watermark: 64I couldn't find errata for LIS2DUXS12. Questions:1. Is th

I've installed MEMS Studio v2.3.0 and trying to evaluate ST1VAFE3BX sensor -- in particular the vAFE ONLY operation in FIFO mode -- using the STEVAL-MKI109D evaluation board with STEVAL-MKI250KA evaluation kit plug-in module. Previously I had MEMS Studio v2.2.0 installed and that was working. I've just updated to v2.3.0 and now the setup is not working.- I did update the FW on the MKI109D board; MEMS Studio indicates "FW: 2.6.17".- I see a tiny fraction of a second of data in the plot window, and then nothing.- The pink "Run" button becomes grayed out/deactivated.- Most options typically under the "Sensor Evaluation" panel disappear. How do I use MEMS Studio to evaluate the ST1VAFE3BX sensor in "vAFE only" mode?