MEMS (sensors)

I am using the mp34dt05-a mems microphone and receive the PDMdata stream. Now I want to do the signal processing as recommended in application note AN5027: "Interfacing PDM digital microphones using STM32 MCUs and MPUs". Thus after receiving the PDM data stream I want to do the PCM conversion as decimation stage. The decimation factor is in the range between 48 to 128 but it depends on the audio sampling frequency of the mp34dt05-a microphone. Unfortunately I can't find any note in the datasheet despite the input clock frequency which is in the range of 1,2 MHz to 3,25 MHz. Does anybody know which audio sampling frequency is used in the mp34dt05 microphone?

Hi, just want to give some reply on "bugs" I found in my sensortile.box.1. Battery capacity always showing 0% even after loading for 2 days and voltage is showing 3.9V2. The date of my logfiles jumped from 31.12.2019 to 01.01.2000. :)3. The csv files get so large that they cannot be imported to Libre Office -> a split up in several files with a maximum entry number would be usefull.Where to report such topics?Best wishes,Stefan

Hi, I am working with LSM6DS3TR sensor and need some advice on FIFO usage. I have followed sample code from the ST's GitHub page but still have some questions. I am using continuous-to-FIFO mode and tap interrupt.I see samples on my screen when interrupt happens. Do these samples come from FIFO or from the present state of the IMU?If coming from FIFO, I am unable to get more than 350 patterns. In code below, it prints 300 samples. How do I get more patterns?The FIFO can memorise 4096 samples of 16 bits each. Does this mean I can have 4096 samples of data or 4096/16 samples? //Set FIFO watermark to a multiple of a pattern pattern_len = 6; pattern_numbers = 300; lsm6ds3tr_c_fifo_watermark_set(&lsm6ds3, pattern_numbers*pattern_len); lsm6ds3tr_c_fifo_stop_on_wtm_set(&lsm6ds3, PROPERTY_ENABLE);   //Set FIFO mode to Stream-to-FIFO mode lsm6ds3tr_c_fifo_mode_set(&lsm6ds3, LSM6DS3TR_C_STREAM_TO_FIFO_MODE);   //E

Dear friends, help me please solve the problem that I encountered during the calibration of the LSM303 DLHC magnetometer. I use the technical documentation stm32 AN3192 for calibration. After rotation of the sensor along each axis and data collection, correction factors for displacement and normalization are calculated. Given these coefficients, I should get a normalized sphere with a radius of 1. However, this does not happen. After that, I separately display the calculated values ​​of the calibration coefficients. Can elements A, B, C be negative values?Tell me what can be caused by their negative values?

I know the theoretical values of sample length and window length. However, I do not know if this parameter is linked to the Accelerometer ODR, or the MLC ODR. Currently, my MLC is at 104 Hz, while my Accelerometer ODR is at 6666 Hz. What calculation/values are "standard"? What is a good way to go about with these MLC and Acc. ODR's?Thanks!

We have a IMP34DT05 interfaced with a STM32L486 on PDM. We are observing that, after the clock to the MEMS is enabled and the sampling is started, in the first 10 seconds unexpected db values are calculated (higher than expected: 80 db). Then, the value gradually goes to the real one (40 db) in about 10 seconds.Is this an expected behavior? Thanks

Hi all, I use in my project the LIS3DH. Driver from Tota. Now I want use the new version LIS3DSH. But don't work. Where find the upgrade driver. For I2C protocol?Thanks ​

Hi everyone. I'm using MotionGC library to calibrate my LSM6DSL gyroscope. In User Manual of library it is stated that "void MotionGC_Initialize(float freq) "function takes "float" as input argument. But when I call the function according to the user manual, I got a Hard Fault. If I pass the frequency variable input as its address and define Init function as "void MotionGC_Initialize(float *freq)" no faults observed, it looks like it works but I can not be sure if its working properly. Calibration process takes much time.Is there anyone who had any experience about this problem?Thanks.

Hi,I am using the lsm9ds1 with a selfmade circuit, but I could not get any data from the sensors. The I2C works fine. I can access the registers, read and write to them and get an acknowledge from it, but when I read the data registers, the values don't change even when bdu is disabled. Does anyone know what problem could be causing this?schematic:IMU setup://setup IMU I2C_Mem_Read(LSM9DS1_IMU_I2C_ADD_H, LSM9DS1_CTRL_REG2_G, (uint8_t*) &ctrl_reg2_g, 1); I2C_Mem_Read(LSM9DS1_IMU_I2C_ADD_H, LSM9DS1_CTRL_REG3_G, (uint8_t*) &ctrl_reg3_g, 1); I2C_Mem_Read(LSM9DS1_IMU_I2C_ADD_H, LSM9DS1_CTRL_REG7_XL, (uint8_t*) &ctrl_reg7_xl, 1); I2C_Mem_Read(LSM9DS1_IMU_I2C_

Could anybody explain me about the purpose of GPIO that present in the sensor. How can we use that for an application, then there is a constant output voltage at range of 3v3 (when we give input voltage as 3v3 to sensor to work) is this voltage can be use to drive any external device or not. When we connected to the ground there no change in the sensor.

Hi,I'm acquiring gyros and accelerometers data through i2C bus, pulling the data from the FIFO asynchronously from the component acquisition frequency, but at a frequency close by (to avoid overfilling the FIFO).Without metrological tools, I can still confirm readings are OK ( "g" on the axe pointing downward, sign of rotation etc ...).However, when looking closer to the data, some are duplicated from one FIFO emptying to the next:LSM is acquiring at 59.5Hz. I've tried to collect at several frequencies: 60Hz, 50Hz, 40Hz or 200Hz. Behavior occurrence vary, but is always present. Also, as visible on the table, it is not systematic, but when happening it is always first sample compare to last sample

When the sample source code taken from STSTSW-STLKT01, the codes for the accelerometer is run and processed smoothly. However, the raw data and characteristics are not displayed in the nRF Connect app. No changes were made to the codes for the accelerometer and other functions & characteristics. The ST BLE Sensor Application shows no problem with the accelerometer. Other functions such as accelerometer events, battery and carry position are displayed. I am using the SensorTile module (STEVAL-STLCS01V1) with STM32L476JG, LSM6DSM, LSM303AGR, LPS22HB, MP34DT05-A, BlueNRG-MS, BALF-NRG-02D3 and LD39115J18R. May i know how do i display the data and characteristics?

I have 2 LSM9DS1 9 axis chips and after waving them around I have the following min / max magnetometer values:chip1:X max/min: 657/-396Y max/min: 598/-417Z max/min: 377/-654chip2:X max/min: 533 -515Y max/min: 788/-284Z max/min: 0/-1213...that last Z max/min on chip2 looks bad. How does it look to others? Are these chips (roughly) calibrated at the factory? Is there a setting inside the chip that can fix this - if it is a problem?-thanks

I see that i2c operate up to 400Hz

Any ideas why LIS3DH is not consuming current as per data sheet which is 6uA whereas I am getting about 200uA.I have kept CTRL_REG0 at default.Would could be the problem?

I get an error when connecting to the board that the WHO_AM_I register value does not match the device selected. The correct device does appear in the Unico GUI menu (STEVAL-MKI206V1 (AIS2dw12). I also have updated my firmware today, the demo board firmware version is: 3.6.13. I am able to verify the WHO_AM_I register on my own fixture (0X44). But I wanted to use the demo board to exercise some more functions as a reference for my own board.

​1 :i only use the Lis3dh ,and remove all other elements ​2: i use the power 3.0V, i use multimeter test the current consume between VCC and GNDget the test result current is 16 μA,（the spec says ,the device automatically enters power-down mode, and current is 0.5μA）​3, then i add the R1,it used for wake up the MCU,and connect to Lis3dh int 1 port ,then a test the current like before ,but get the current is 56​μA, it is beyond my imagination .​so i want to ask ,is there anything wrong ?why i cannot get the power down mode current consume like spec says ?​​​

Hello, I am simply tring to communicate with the L3GD20 Gyrosensor using the WhoAmI command. I am sending 0x0F and i'm expecting 0xD7 back (11010111) but I only received 0xFF which means i'm doing something wrongI am using STM32CubeMX to generate the code , Keil IDE and using STM32L071 https://www.mouser.co.uk/datasheet/2/389/l3gd20h-954865.pdfAny help would be appreciated!//put CS low HAL_GPIO_WritePin(GYRO_CS_GPIO_Port,GYRO_CS_Pin,GPIO_PIN_RESET); //Transmit register address spiData[0] = 0x0F; HAL_SPI_Transmit(&hspi1,spiData,1,10); //read HAL_SPI_Receive(&hspi1,&spiData[1],1,10);   //put CS High HAL_GPIO_WritePin(GYRO_CS_GPIO_Port,GYRO_CS_Pin,GPIO_PIN_SET);

I've generated project for SW4STM32 and i don't know that to do with iks01a2_conf_template.h file. Im supposed to replace the header file names with the ones of the target platform and rename the file to iks01a2_conf. There are 3 headers:#include "stm32yyxx_hal.h" #include "nucleo_xyyyzz_bus.h" #include "nucleo_xyyyzz_errno.h"I changed first one to "stm32f1xx_hal.h", but I don't know what to do with rest of them. I've tried several names but none of them were found. What are the header files i'm supposed to use there? My hardware is: STM32F103RB and X-NUCLEO-IKS01A2.

Is the source code for ST.COM's X-CUBE-MEMS1available? I am using an STM32L412. And when I try to include the STM32 pre-compiled library into my project I get errors. I am thinking the processor I am using is not compatible with the libraries. So I'd like to try using the source code instead.-thanks

I am interested in utilizing vetted STMicro LSM9DS1 software calibration tools and other STMicro "Middleware".  I had assumed STMicro would support their own chip in order to encourage sales. But, the STMicro's LSM9DS1 chip is not supported in X-CUBE-MEMS1 according to the release notes found here (LSM9DS1 is not to be found anywhere in this document):file:///C:/Users/ricks/proj/st/x_cube_mems1/en.x-cube-mems1/STM32CubeExpansion_MEMS1_V7.0.0/Release_Notes.html

We are affraid when one device has CS signal down, other devices will be set to I2C there can be conflict on the SPI BUS. Is it possible connect more devices as eclosed schematic?

Hi, I want to use -CUBE-MEMS1 for lsm9ds1. By default the applications code uses LSM303AGR . Could any one give me some hints what changes I need to do for porting ECompas application for lsm9ds1. I have already ported the driver accelerometer, gyro and magnetometer for lsm9ds1. I am asking for application and mathematics difference as done in Ecompas application code. Axis orientation is different for these two chips.. How to handle that difference in source code. Here is link for for X-CUBE-MEMS1 https://www.st.com/content/st_com/en/products/embedded-software/mcu-mpu-embedded-software/stm

Hello all,I am having an issue with single-click detection. I am getting false click detections at certain threshold values. I found this out yesterday when I had an MCU register lots of clicks repeatedly, but the device was not being shaken.To test, I set up the LIS2DH as follows (using I2C):Reset chip (write CTRL_REG5 with 0x80)Read WHOAMI until it returns 0x33 to make sure it's upDisable ODR and enable all 3 axes (write CTRL_REG1 with 0x07)Write CTRL_REG2 with 0x00 (just to be sure)Send Click to INT1 pin (write CTRL_REG3 with 0x80)Set BDU so I can read values, +/-2g, normal mode (write CTRL_REG4 with 0x80)Set up temperature (write TEMP_CFG_REG with 0xC0)Run Self test (Sets ODR to max, sets SELF_TEST_0, sets back to normal, test passes)  Enable click interrupts on all 3 axes (write CLICK_CFG_REG with 0b010101)write CTRL_REG5 to 0x0Set ODR to 10Hz (write

(Because I am not good at English, I used Google Translator.)​I'm using the LSM6DSL sensor now. I think that with this sensor still, the total gravity acceleration should be 1G, or 9.8.( Total - G - Force = SQRT(x^2 + y^2 + z^2 ) ) ​However, as the sensor's position or inclination changes while it remains stationary, it brings a different value from 9.8 to 10.3.​I wonder if you should correct each axis by angle when measuring the total gravity in a stationary state.​If you know or have experienced these problems, can you give me advice?​( LA_So - FS = +-2, type = 0.061 mg/LSB )thanks for reading.have a nice day ^^*​​​​