MEMS (sensors)

Hello everyone, I'm contacting you today in order to understand my error during the calibration of my LSM303AGR sensor located on a PCB. The ultimate goal is to create a compass with tilt compensation but I try to get a good precision with magnetometer first. Of course, I took care to read up on the Internet before opening this post, but all the ideas seem to be divergent and I can't find my way around. First, I got the raw acceleration and magnitude data from my sensor. So far, so good. As part of my calibration, I generated a data set during which I rotate the sensor in all possible directions to cover all angles. I then measured the hard iron to eliminate offsets on each axis :       def calculate_hard_iron(data): max_vals = np.max(data, axis=0) min_vals = np.min(data, axis=0) return (max_vals + min_vals) / 2       Then I calculated the soft iron by normalizing my data while preserving the centering :       def calculate_soft_iron(data

I am using the sensor LIs2DH, and I've read the datasheet and tried multiple values and manipulations of its registers.Now I want to use the sensor should be on a car and detect when will the car move.the problem I'm facing that it generates an interrupt at any vibratoin/touch on the board, and I want to avoid that.Also what are the best configurations for a free fall detection (because I think that would be the best solution for my case) Thanks in advance Register values are Register 0x0f has 0x33Register 0x20 has 0x27Register 0x21 has 0x00Register 0x22 has 0x40Register 0x24 has 0x08Register 0x25 has 0x00Register 0x30 has 0x2aRegister 0x32 has 0x27Register 0x33 has 0x00Register 0x34 has 0x00Register 0x36 has 0x00Register 0x37 has 0x00Register 0x2e has 0x00

Hello,  I use LSM6DSO with my stm32L476. I use I2C 100kz with 10k pull up resistor. The LSM6DSO is next to the STM32. I use INT1 with wakeup parameter to indicate the movement and wake the STM32.I have a problem, sometimes the LSM6DSO freeze. There is no edge to INT1 pin and we cannot communicate throught the I2C bus. So I cannot reset by I2C. I don't understand why, it can appears after 1 weeks or 3 months of uses. It depends. I have to cut off the power to resolve the issue. The LSM6_INT1 pin directly connected to the STM32.   Thank you for your time Aurelien 

I'm encountering many issues while using the AIS2120 accelerometer sensor and would greatly appreciate your assistance. Thank you very much!After the sensor is powered on, a series of initializations (default configuration) are performed, then it enters normal mode, and then the corresponding acceleration data is read. Are these actions performed automatically by the sensor?Do I need to perform any operations to make the sensor enter normal mode?If I need to set it to 1600Hz, how should I operate? (I tried setting a soft reset and then writing to the configuration register, but it didn't work).I keep having communication issues, especially I'm not sure if the CRC check is correct. The manual is very vague. Attached is my CRC check function.I'm also unsure how to fill in the position indicating whether it is sensor data in the SDI frame.uint8_t AIS1120SX_ubCrcVal(int32u ulCrcVal) { uint8_t crc = 0x00; uint8_t poly = 0x97; for (uint8_t i = 0; i < 4; i++) { crc ^= (uint8_t) ((ulC

The datasheet of STM32U585 say that "For operation with voltage higher than Min (VDD, VDDA, VDDUSB, VDDIO2) +0.3 V, the internal pull-up and pull-down resistors must be disabled." (chap. 5.3.1).The STEVAL-STWINBX1 use a VDDA of 2.75V and a VDD of 3.3V => Min (VDD, VDDA, VDDUSB, VDDIO2) +0.3 V = 3.05V < VDD = 3.3V.But in the examples provided for STEVAL-STWINBX1, pull up and down are used with a VDD of 3.3V.So which is correct, the datasheet or the examples ?

I am using the STHS34PF80 IR presence/motion sensor on a Linux platform . According to the datasheet, the sensor can detect human presence up to 4 m (for a 70×25 cm² object).Currently, my configuration is as follows:echo 1 > /sys/bus/i2c/devices/3-005a/iio:device5/algo_resetecho 4 > /sys/bus/i2c/devices/3-005a/iio:device5/sampling_frequencyecho 2 > /sys/bus/i2c/devices/3-005a/iio:device5/lpfecho 3 > /sys/bus/i2c/devices/3-005a/iio:device5/sensitivityecho 150 > /sys/bus/i2c/devices/3-005a/iio:device5/thresholdecho 50 > /sys/bus/i2c/devices/3-005a/iio:device5/hysteresisecho 1 > /sys/bus/i2c/devices/3-005a/iio:device5/scan_elements/in_temp_y_enecho 1 > /sys/bus/i2c/devices/3-005a/iio:device5/events/in_temp0_thresh_rising_enecho 0 > /sys/bus/i2c/devices/3-005a/iio:device5/buffer0/enableecho 256 > /sys/bus/i2c/devices/3-005a/iio:device5/buffer0/lengthecho 1 > /sys/bus/i2c/devices/3-005a/iio:device5/buffer0/enableHowever, in practice, I am only getting a dete

Could anyone give me some advice on debugging the AIS2120 accelerometer sensor? I've included my CRC check function above, as well as the data sent and received via SPI, but I still can't read the correct sensor ID. Thank you very much for your help!

Is this the correct way to calculate the CRC check code?

Hello,It seems that the library MotionMC_CM7F_wc32_ot_hard.a is missing the called function, here the error :c:\st\stm32cubeide_1.6.0\stm32cubeide\plugins\com.st.stm32cube.ide.mcu.externaltools.gnu-tools-for-stm32.9-2020-q2-update.win32_2.0.0.202105311346\tools\arm-none-eabi\bin\ld.exe: ../Middlewares/ST/STM32_MotionMC_Library/Lib\MotionMC_CM7F_wc32_ot_hard.a(motion_mc.o): in function `MotionMC_Initialize':motion_mc.c:(.text.MotionMC_Initialize+0xde): undefined reference to `MotionMC_SaveCalInNVM'c:\st\stm32cubeide_1.6.0\stm32cubeide\plugins\com.st.stm32cube.ide.mcu.externaltools.gnu-tools-for-stm32.9-2020-q2-update.win32_2.0.0.202105311346\tools\arm-none-eabi\bin\ld.exe: motion_mc.c:(.text.MotionMC_Initialize+0x1fc): undefined reference to `MotionMC_LoadCalFromNVM'I'm just doing like the example, I erased and reinstalled MEMS and this library at the previous version but nothing changes, can you help me ?Here the call :#define VERSION_STR_LENGTH 35#define SAMPLE_TIME 20/* Magnetometer

Hi!I have set up and connected a LSM6DSV16X via I2C to my raspberry pi, its on bus 10, address 0x6a. The sensor seems to have been detected via an I2C dump but the identifier (which should be 0x70) is stuck at 0x00 and I'm not sure why. azlan@argo:~ $ i2cdetect -y 100 1 2 3 4 5 6 7 8 9 a b c d e f00: -- -- -- -- -- -- -- --10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --30: -- -- -- -- -- -- -- -- UU -- -- -- -- -- -- --40: -- -- -- -- -- UU -- -- -- -- -- -- -- -- -- --50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --60: -- -- -- -- -- -- -- -- -- -- 6a -- -- -- -- --70: -- -- -- -- -- -- -- --azlan@argo:~ $ i2cdump -f 6 0x6a0 1 2 3 4 5 6 7 8 9 a b c d e f 0123456789abcdef00: 48 05 3d 3a 20 13 5e 9d 03 44 93 e2 80 13 00 00 H?=: ?^??D????..10: 00 00 00 08 39 ff ff ff ff ff ff ff ff ff ff ff ...?9...........20: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................30: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

Hi,I am trying to capture data from the IIS3DWB sensor at its maximum rate and save it into a buffer of length 8192 (due to internal RAM limitations). I'm using SPI with DMA to interface with the sensor. However, I'm not able to capture the data correctly — the X-axis shows incorrect values, while the Y and Z axes remain constant. I tested with another sensor, but the issue persists. The FIFO is configured to stream mode. I haven't detected any buffer overflows. I'm attaching the code and a CSV file for reference. SETTINGS: SPI clock-8MHz, iis3dwb stores data in FIFO in continuous mode with 26.67k ODR , 3-axis mode is used, timestamp batch to FIFO is on, BDU is on, 16G range mode is on, IRQ pin -not connected, using polling mode. can anyone give me solution. Thanks 

Hi ,We need a clarification in the register values of LSM6DSL for configuring g values. Is this the correct values or is it a printing mistake where 16g is given as 01 ,should'nt this value be allocated to 4g .It would be appreciated if you can kindly clarify at the earliest.Thanking youRegardsGouri.k

Hi,I am trying to use the LIS2DU12TR's low address that is 0x18 but I keep on encountering issues with not able to read WHO_AM_I and the accelerometer does not work. Can anyone please help me with this?Also, does it support 100kHz I2C bus?Thanks.

Problem SummaryI'm experiencing challenges with MotionFX library for azimuth rotation detection using the ISM330DHCX sensor. While MotionDI works well for altitude detection, MotionFX shows inconsistent behavior for azimuth (rotational) measurements.I have done a test where I have collected samples over the entire weekend (about 65 hours). I am aware of the difficulties in detecting rotational movement using only accelerometer and gyroscope, however, the issues below do not seem to stem from this, but rather with issues in the MotionFX library or parameters.Hardware SetupSensor: ISM330DHCX (accelerometer + gyroscope)Orientation: WDS mounting (X-West, Y-Down, Z-South)Sample Rate: 104HzApplication: Rotational motion detection system that detects motion over longer periods in time. (No real time updates needed)Current ConfigurationMotionDI Parameters (working well for altitude):mdi.move_thresh_g = 0.25f; mdi.cal_type = 1; mdi.acc_thr_g = 0.01f; mdi.gyro_thr_dps = 0.01f; mdi.max_gyro_dps =

 Hello everyone,I am using I2C to communicate between an STM32F411 Discovery Board and the on-board LSM303AGR sensor. I have already configured it for a 400Hz ODR, normal power mode, and am reading temperature values (around 25°C to 27°C).However, I am stuck on how to soft-reset the entire sensor. I tried to SET bit 5 in CFG_REG_A_MAG and adding a small delay, but this does not reset the values I configured in other registers. Those settings remain the same, no matter how many times I try to SET the reset bit.The registers only reset when I unplug and plug the power back in.Please help me.Thank you very much.bool LSM303AGR_softReset(const LSM303AGR_t* lsm303agrStruct){ uint8_t regVal = 0; if(!readMag(lsm303agrStruct, LSM303AGR_CFG_REG_A_MAG, &regVal)) return false; //Extract the current status bit-field and assign it to regVal /* Start to assign and write regVal to CFG_REG_A to start FULL CHIP RESET */ regVal |= (SET << REG_A_SOFT_RST_Pos); if(!writeMag(lsm303agrSt

Hi, I was trying to make the sensor sense slow rotation.I read the datasheet and I guess if I set HPM to work as normal mode, and High-pass filter for interrupt 1so CTRL_REG2 should have 0x81,Then I should read the REFERENCE (0x26) register, (according to the thread in here https://community.st.com/t5/mems-sensors/lis2dh12-measure-conversion/td-p/420708) My question is, is it even doable ? Can I sense slow rotations until it reaches some point ?Thanks in advance 

Thank you for your continued support.From your responses, I have made the following initialization procedure for ASM330LHH.POWER ONCTRL3_C <- 0x42(BDU,IF_INC)CTRL1_XL <- 0x9C(3333Hz,8G)CTRL2_G <- 0x92(3333Hz,125dps)INT1_CTRL <- 0x01(Accelerometer data-ready interrupt)Read STATUS_REG every 0.5ms to check if TDA is 1.Some units do not set TDA to 1. This is a problem.Is the ASM330LHH initialization procedure correct?Do I need to wait, etc.?

Hi,I am developing an application using the accelerometer LIS2DH12 and a STM32L451. It works perfect but I get some kind of issues when temperature is low. I used a thermal chamber to perform this test and it seems very repetible.If the accelerometer is set in low power mode and disabled at the beginning, what I do is:1) Initialize I2C HAL interface.1) Configure the accelerometer. (ODR 10, PW normal, FS 2G)2) Enable X, Y, Z axis3) Wait for 100 ms4) Read XYZ flag (Register 0x27) until it says values are updated. 100ms between retries.5) Set BDU to 1 in register CTRL 4.6) Read 6 registers XL, XH, YL, YH, ZL, ZH. I haven't been able to read 6 at once. It always fails or returns 0 for all the axis.7) Set BDU to 0 in register CTRL 4.8) Wait for 1 second, and go to number 1.In case the temperature is over 7ºC, I always get good results. Once the temperature drops 7ºC, I always get value for X axis and 0 for Y and Z axis. The pcb is not moving at all.After the temperature stops decreasing at

HiIs it possible to configure the interrupt function for free-fall with normal XYZ polled operation, or is it better to use the interrupt in low power mode and performing the free-fall via normal XYZ programmatically in normal operation?Thanks! 

Regarding the statement in the ASM330LHH datasheet “Embedded compensation for high stability over temperature”, does this mean that each output is temperature compensated? Does the compensation value correspond to the memory contents loaded when the BOOT bit is set? What output behavior is expected if this read/boot operation fails? 

When I try to set the LIS2MDL's operation mode from IDLE to CONTINUOUS or SINGLE_TRIGGER mode, the register values in CFG_REG_A that I already set prior (including comp_temp_en) gets reset to default including the operation mode when I check the register after a 7ms delay. I am using functions from the lis2mdl_reg.c/h files and have read values on hardware debug mode and on the SDA line. I have checked that 3V3 does not drop out and I2C communications look expected. Does anyone have any insight into what could be causing this?

Hello, I recently integrated LSM6DSOX on a testing PCB which contains an MCU and some other peripherals. The problem is that I have been trying to reduce power consumption without success, and I thought maybe you could help me find the problem. First, the application also uses BLE, and I measure power consumption during advertising, connecting and other states. Before the LSM6DSOX, the consumption was around 45-60 uA during these states. After integrating it, the consumption rose up to ~97-140 uA, which is unexpected as I have confirmed it to be low power mode. I also confirmed that the previous code with the current board with LSM6DSOX also consumes around 45 uA, so I assume there is something wrong in the code, handling, configuration etc. Hardware details: 1. I have connected a MOSFET as a switch before the power pins of LSM6DSOX. Meaning, I set high/low the gate of the mosfet to give power to VDD and VDDIO pins. I thought this was something t

How to know  MotionMC and MotionEC Library minimum Stack size Heap_Size?When I invert my compass,stm32 will reset, then i  increase Stack size Heap_Size,it run very well.

Hello, I am designing a PCB board using LSM6DSO and STM32f1xx, this PCB design will be only an experimental design for a bigger project, so I need both SPI and I2C to be available for testing (not at the same time).I'm wondering if there will be any issues regarding having both of them, espcially from the HW side, and is there any considerations or something to keep in mind when designing the PCB.Thanks! "Design schematic, typical connection for mode 1"

HiWe are testing out the lsm6dsv320x, which will be used on our new board.The low G accelerometer is working fine, however the high G looks to be reporting wrong values.If I use a simple calculation to computer the angles, the high G  is off by about 3-4 degreesThis is the formula i use to calculate the angles AccXangle = (math.atan2(ACCy,ACCz)*RAD_TO_DEG) AccYangle = (math.atan2(ACCz,ACCx)+M_PI)*RAD_TO_DEGBelow is an example of the results of both formulas when the sensor is horizontal. The last two columns are for the high G sensor.  you can see that it is different from the low G sensor. My expectation is that they should be reporting the same result.ACCX_angleACCY_angle ACCX_HG_angleACCY_HG_angle-0.06-0.20 -4.44-4.6200.03-0.17 -3.67-4.1200.03-0.23 -3.84-3.610-0.03-0.17 -3.61-4.240-0.03-0.17 -2.91-5.1300.03-0.20 -3.50-4.2400.00-0.20 -4.47-3.0800.00-0.20 -3.05-5.6800.03-0.20 -4.15-4.380-0.03-0.20 -3.71-3.250-0.03-