MEMS (sensors)

Let's start this diving into the FW libraries for ST motion MEMS sensors with the first one: Motion Automatic Calibration (MotionAC). It provides real-time accelerometer calibration through offset and scale factor coefficients used to correct accelerometer data.Why should you need a sensor auto-calibration? Because it simplifies and improves the reliability of you application: accuracy is one of the key-words of the state-of-art of MEMS sensors. ST sensor are of course calibrated at Automatic Test Equipment level,

Hi,I'm using LSM330DLC on my board and I've configured low power mode (accelerometer enters the low power mode in case of inactivity, and goes back to normal mode if I touch/shake it). What I would like to know - if there is any way to know that accelerometer entered the low power mode? In that case I would like to put gyro and MCU into sleep mode and wake up on the interrupt from accelometer.

Hi,  Will the data in FIFO mode get refilled automatically after finishing reading the FIFO (till empty)? Based on my code, the data does not seem it refills unless I use the bypass mode. However, I am trying to avoid bypass mode. Is there a way to do it without using the bypass mode? Thank you

Hello ST team,In document https://www.st.com/resource/en/datasheet/lis2dh.pdf , on page 38:7.17  FIFO_CTRL_REG (2Eh) FTH[4:0] bits are not well documented, I assumed name "FIFO Threshold" which is referenced on page 21 as "FIFO_WTMK_LEVEL bits"...7.18  FIFO_SRC_REG (2Fh) FSS[4:0] bits are not documented. By reading datasheets of similar devices I suggested name "FIFO Stored Sample

Hi,I am trying to read data from the IIS2MDC placed on a STEVAL-MKI185V1 on a STM32F103C board programmed via Arduino IDE. I tried following the steps mentioned in the document in the link:https://community.st.com/s/question/0D50X00009yDgrUSAS/is-there-any-description-initialisation-sequence-to-get-the-master-i2c-of-the-ism330dlc-running-mode2However when I read the WHOIAM register it gave a value of 0 instead of 0x40. Subsequently I am unable to read the magnetometer register values. PFA the code that I am working on.Any help for this is much appreciated.

Although this post series will be mainly focused on the library package X-CUBE-MEMS1 and on the related motion algorithms, it's worth spending a few words on the overall family of software tools developed by ST for MEMS sensors --> this linkMEMS drivers are open-source and allow using 

Hello,I am using the ​L3GD20H Motion Sensor for flight application and I need to compensate for temperature variation. There is a registry that I can read that provides a temperature value. Could you tell me what this value means and what it is referenced to? At 22C the value is 5, when I freeze the chip the value is around 14. How is this value used to correct the reading as a function of temp?Regards,

I downloaded linux driver for LSM6DSL from official ST repositiory (https://github.com/STMicroelectronics/STMems_Linux_IIO_drivers/tree/linux-4.9.y-gh ) and seems that It works as expected. One problem is that I can't find place where I can read temperature from OUT_TEMP_ register.Is it somewhere hidden in IIO directory structures or this is not provided (most probably - based on sources) ?Thanks

In the datasheet Twait was added to inform us to delay between powering up Vdd_IO and Vdd. However, the Twait timing says that there should be 0-10 mS wait period between Vdd-IO and Vdd. After waiting 0.1 - 100 ms Rise Time for Vdd-IO. What is the Twait time for? What is the danger of powering Vdd-IO and Vdd together?

Hi, I try to connect a Nucleo-144-Board to Audacity. The Project is based on CubeMx5.2/STM32Cube_FW_L4_V1.14.0. I've read (successfully) in a Mems-Mic via SAI1/DMA2. The USB-Audio-Device is shown in the Device-Manager and seems to be OK. I've read the the UM1734 Rev.4 At the Moment I don't understand the Data-Direction of USB-Device (Middleware).USBD_AUDIO_DataIn means Data-stream STM32L4->PC-USB-Host ??USBD_AUDIO_DataOut means Data-stream PC-USB-Host->STM32L4 ?? Is DataIn() implemented at all? I've found the "STM32CubeExpansion_MEMSMIC1_V4.0.0/Microphones_Streaming"-Example. there is a file: ...\STM32CubeExpansion_MEMSMIC1_V4.0.0\Middlewares\ST\STM32_USB_Device_Library\Class\AUDIO\Src\usbd_audio_in.c with Function "USBD_AUDIO_Data_Transfer()" Is this the Way to do the job? Confused a little

VL6180X software graphical user interface (GUI):with the TAB Options the Flash action can be performed, but I can't find any documentation.

I am using an ISM330DLCTR IMU currently and have a FIFO running in continuous mode with an ODR of 6.66kHz. I was trying to get the accelerometer and gyroscope to both run at ODRs of 6.66kHz, but when I try this, most of the data is garbage. It seems like when all three ODRs are set to 6.66kHz the first two or three samples are good values, but then everything else is nonsensical. If I lower the accelerometer and gyroscope ODRs, the data looks better and better. If both are set to 833Hz, everything looks good. Are there some sort of ODR limitations when using the FIFO in continuous mode? I couldn't find anything in the datasheet that mentioned ODR limitations, so it's possible that I'm setting something else up wrong.This is my register configuration if it helps (everything else is set to default):IMU watermark threshold is set to 48 in the FIFO CTRL1 registerIMU full threshold on interrupt pin 1 is set in the INT1 CTRL register6.66kHz ODR and 2g fu

This software is based on the STM32CubeHAL hardware abstraction layer for the STM32 microcontroller. The package extends STM32Cube by providing a board support package (BSP) for the sensor expansion board. The drivers abstract the hardware low-level details and allow the applications to access sensor data in a hardware-independent manner. The package includes several sample applications that the developer can use to start experimenting with the code. A sample application has been developed to enable sensor data logging on a PC; a Windows PC utility (Unicleo-GUI) is available, to allow the devel

Dear Members,I have a state machine but it seems that it stuck in one state,Is it related with stack size ?It's stuck on "case PULSE_IDLE" no matter the value of sensor_value,The code :switch(currentPulseDetectorState) { case PULSE_IDLE: if(sensor_value >= PULSE_MIN_THRESHOLD) { //printf("Sensor_value PULSE_IDLE %f \r\n",sensor_value); currentPulseDetectorState = PULSE_TRACE_UP; values_went_down = 0; printf("PULSE IDLE\r\n"); return true; } break;   case PULSE_TRACE_UP: printf("Sensor value PULSE_TRACE_UP %f\r\n",sensor_value); if(sensor_value > prev_sensor_value) { printf("PULSE TRACE_UP\r\n"); currentBeat =HAL_GetTick(); lastBeatThreshold = sensor_value; } else {   printf("Peak reached: "); printf("%f \r\n",sensor_value); printf(" "); printf("%f \r\n",prev_sensor_value);   uint32_t beatDuration = currentBeat - lastBeat; lastBeat = currentBeat;  

Hi, From what I've been told, the LIS3MDL magnetometers self-calibrate upon turning on. I have taken some readings from 3 different LIS3MDL's and plotted the values in a similar way to the beginning of this tutorial: https://thecavepearlproject.org/2015/05/22/calibrating-any-compass-or-accelerometer-for-arduino/My plots, which I will include, show quite significant hard and soft iron distortions. So, it seems that the magnetometers are not correctly calibrating when powered on / are not calibrated.How could I go about calibrating them?The data points here I took by taking 750 readings with a 0.1 sec delay between each. I moved the magnetometer around in the air to tra

I am running Windows 10 and installed the latest version of Unico GUI. The device is new. Is the software not yet supporting the device or am I missing something.

Regarding this thread:https://community.st.com/s/question/0D50X00009XkX2bSAF/lsm6ds33-problem-with-self-test?t=1558067735502The last comment by Petr says that the self-test values such as Min(ST_X) are derived from the Full Scale range, but he doesn't explain how to calculate them.Can someone please provide the derivation for those values of 90 and 1700 for accelerometer, and 150 and 700 for the gyroscope? I'd like to extend the self-test to other Full Scale ranges.

I have a Nucleo board with an IKS01A2 expansion board. I can address the sensors on that board over i2C to read registers on the sensors, using the HAL library calls. However, I plug an STEVAL-MKI174 board into the 24 pin socket and try to address it, but can never get a response. The datasheet for the sensor on that board (LIS2HH12) says the address should be 0x1e (I have verified the address pin is pulled low to correspond with this address). Has anyone had luck communicating with such an add-on board or similar? Thanks

MotionFX,LSM6DSM,LSM303AGR,Sensor fusion,Mechanical Shock,Vibration

Our existing products are using NXP MCU and IMUs. We plan to switch to ST IMUs for the next generation, but still keep the existing nxp mcu. Is this possible? Can motionFX work in different mcu (m4f)? thanks!

Hi guysI configured the FIFO mode in LSM6DSL to extract the timestamps and Accel and gyrodata, and the data can be extracted properly. ​Since I now prefer to extract data consistently from the fifo for a long time, I switched to FIFO continuous mode. However, the timestamps and the data pattern is not exactly correct every time. The patterns are correct every couple second, and they are not always zero. I originally set the FIFO ODR is 833Hz with no decimation factor . My SPI speed is set to 10MHz. I thought the speed should be faster than the FIFO ODR, but it seems the FIFO is always full when I uses 833Hz, I was concerning that the fifo was always full might be the reason that the pattern was messed up. So I decrease the ODR to 104 Hz, the FIFO was pretty empty at the beginning, but after a couple runs, the FIFO become very close to full again. It appears that the fifo pattern is more stable when I use low ODR but it is not a

Hi friends,I want to measure the distance to an obstacle (120 mm) with the VL53L1X, but I am having problems with the repeatability.NOTE: I measure 10 times to get a sample and I repeat every 10 seconds.These are the results...

I have taken LSM303AGR Driver for development mentioned on this link: https://github.com/STMicroelectronics/STMems_Standard_C_drivers/tree/master/lsm303agr_STdCI am getting issue of interrupt occurs at ODR time instead i require this interrupt should occur on value changed beyond thresold in any direction.Magnetometer Configuration Registers Settings: CFG_REG_A_M = 0x90 (LOW_POWER, ODR_10Hz, Enable temperature compensation)CFG_REG_B_M = 0x02 (SENS_OFF_CANC_EVERY_ODR, CONTINUOUS_MODE)CFG_REG_C_M = 0x50 (Enable Block Data Update, Enable Interrupt)INT_CRTL_REG_M = 0xE7 (All bits set to 1)INT_THS_L_REG_M = 0x64(Threshold LSB)INT_THS_H_REG_M = 0x00(Threshold MSB)

I have VL53L1X-SATEL - Breakout board, I have successfully tested it on Arduino Uno/Mega using Sparkfun's Library (https://github.com/sparkfun/SparkFun_VL53L1X_Arduino_Library) . Now, when I connect the sensors's I2C lines on breadboard It doesn't work. When I connect SCL and SDA of sensors to Controller's SCL & SDA respectively, It works perfectly.What happens if I connect them breadboard and then to the controller? The reason I am doing this is I want to use two sensors so i have to connect them on breadboard and connect and SCL & SDA on same I2C bus.

Any known issues with soldering a STLKT01V1 (sensor tile ) to the small carrier board?I did this, and now it does not work (no jtag) it worked prior with large boardI do not want to destroy a 3rd board!