MEMS (sensors)

Posted on October 23, 2015 at 08:33I am in search of 6 or 9 axis IMU mems sensor for golf swing analyses device. The device would be somewhat like  http://3bayslife.com/zone-1/ Should I go for 6 axis DOF or 9 axis DOF? Low power operation is must. Also the captured data is to be transmitted via bluetooth to smartphone. Suggest me with suitable options for 6 or 9 axis MEMs (which one is better and why?) and also the bluetooth socs that are suitable for this project. #golf-swing-analyses

I am using the STHS34PF80 sensor to detect motion and presence. When I read the raw value of TMOTION and TPRESENCE I get both positive and negative numbers. What does the negative sign indicate here? Thanks

Hi all, I am trying to use the MotionVC library functions to return my vertical speed and calibrated speed, however I have encountered two unknowns: the internal timing or buffer processing of the MotionVC_Update() function and why the calibrated altitude does not update on my personal implementation. I am using the Nucleo-F411RE with the IKS4A1 expansion board and have my accelerometer ODR set to 50Hz. and pressure sensor set to 10Hz (as specified). The function is called once every millisecond (much faster than the data is sampled), the timestamp output parameter is unclear as to what it represents. The data response rate is slow or non-existent for altitude and calibrated altitude/vertical speed alike. If anyone has had any luck doing custom implementations of this library or knows if this function can be tuned to be more responsive that would be greatly appreciated. Thanks in advance. 

Hi everyone,Based on the drivers from ST GitHub, I developed my own one, but I can't understand why it's not working. I can communicate with the accelerometer and I can read the registers, but I don't know why i am having troubles to read the acceleration data correctly.It would be nice if someone knows if it's because I'm not writing to the correct registers at the start-up, or because I'm not reading correctly the acceleration data, so the status register is not cleaned. Thanks!! I attach below the link to my .zip file of all my projectLaraIMK/LIS3DH_HAL_I2C (github.com)

I am using Nucleo F767ZI with SPI interface to ASM330LHHX sensor. I am using example code from https://github.com/STMicroelectronics/STMems_Standard_C_drivers/blob/master/asm330lhhx_STdC/examples/asm330lhhx_read_data_polling.cAfter a couple of seconds "asm330lhhx_xl_flag_data_ready_get" allways returns 0.After power off and power on I get a couple of readings but then again nothing. What am I doing wrong?/* Initialize all configured peripherals */ MX_GPIO_Init(); MX_USART3_UART_Init(); MX_SPI4_Init(); /* USER CODE BEGIN 2 */   platform_init(); platform_delay(BOOT_TIME);   do{ asm330lhhx_device_id_get(&dev_ctx, &whoamI); HAL_Delay(1); }while(whoamI != ASM330LHHX_ID);   /* Restore default configuration */ asm330lhhx_reset_set(&dev_ctx, PROPERTY_ENABLE); do { asm330lhhx_reset_get(&dev_ctx, &rst); } while (rst);   /* Disable I3C interface */ asm330lhhx_i3c_disable_set(&dev_ctx, ASM330LHHX_I3C_DISABLE); asm330lhhx_i2c_interface

I am practicing reading L3GD20 data built into the stm32f411e-discovery kit. I use SPI1 to communicate with L3GD20. I watched on YouTube, they have instructions on how to use the void function HAL_GPIO_EXTI_Callback. I cannot call the void HAL_GPIO_EXTI_Callback function to read data from the sensor. Debug only receives the value from the bar but not the value read from the sensor I use pin PE1 (configuration: Rising edge trigger detection, Pull-up ). Below is an image of my code. I need help. Thanks everyone   

I would like LIS2DH12 to fire Interrupt1 (to wake up the microcontroller) when the device is slightly moved. I have it working if the device/LIS2DH12 is laying flat parallel to the ground, moving it slightly fires the Interrupt. However, if the device the laying at a angle like 30 degrees, moving it slightly does not fire the Interrupt1. Is this not supported or somehow I need to specify the "rest state" so the movement can be compare to it? I am using Arduino IDE.One example of code is attached below that only works if the device is laying flat initially. I have tried other examples with same results. I am not tied to a particular library. Please provide some arduino code that work! #include <Wire.h> #include "SparkFun_LIS2DH12.h" SPARKFUN_LIS2DH12 accel; int accelInterruptPin = 27; void setup() { Serial.begin(115200); delay(500); Serial.println("SparkFun Accel Example"); Wire.begin(); if (!accel.begin()) { Serial.println("Accelerometer not detected. Check

Hi everybody,I'm using a LSM303AGR and I got some difficulties to read the temperature.My I2c functions, because I can read "who am I" registers, and I tried to write then to read some registers. I did the following steps :     LSM303_IO_Write_one_byte(ACC_I2C_ADDRESS,LSM303AGR_CTRL_REG4_A,0x80); for (idx = 0;idx < 50000; idx++) {} LSM303_IO_Write_one_byte(ACC_I2C_ADDRESS,LSM303AGR_TEMP_CFG_REG_A,0xC0); for (idx = 0;idx < 50000; idx++) {} LSM303_IO_Write_one_byte(ACC_I2C_ADDRESS,LSM303AGR_CTRL_REG1_A,0x27);    First, I set BDU, then I set TEMP_EN[1.0], and I configure (HR / normal / low power mode (10Hz)To read the register, I'm waiting for change on TDA bit :      if((LSM303_IO_Read_one_byte(ACC_I2C_ADDRESS,LSM303AGR_STATUS_REG_AUX_A) & 0x04) == 0x04) { LSM303_IO_Read_multiple_bytes(ACC_I2C_ADDRESS,LSM303AGR_OUT_TEMP_L_A,2,(uint8_t *)data_temp); temp = (int8_t)data_temp[1] + 25; }  &nbs

GreetingsIs it possible to run the LIS2DW12 accelerometer for a single sample with its high-pass filter disabled?I am using the FIFO with the high-pass filter enabled for regular sampling on interrupt wake-up, but would like atleast a single sample on demand, with the high-pass filter disabled, after reading the FIFO data.In my INT1 ISR, I have tried turning the filter off after reading all the samples from the FIFO, but no samples are returned. @Federica Bossi 

Hi Team,In our design we planned to use this part LPS25HBTR (Pressure sensor). As per Datasheet Recommended land pattern is not available. Could you please share PCB land pattern for this part LPS25HBTR. Thanks & Regards,Karthikeyan

Hi  Can someone clarify how long it takes for the sensor to temporarily stop reading, execute the SET pulse, and begin conversion when Set_FREQ is set to 1 in CFG_REG_B (61h) while in continuous conversion mode? I noticed that this setting randomly changes my ODR rate.  Thank you. 

Posted on May 22, 2018 at 22:59Hi,I'm currently trying to use the MotionEC library for an E-Compass application, and to calibrate the Magnetometer with the MotionMC library. I'm using an STM32L1-DISCO with an LSM303AGR. My general idea is to run the calibration algorithm for x seconds, then get the calibration parameters, and apply them to the e-compass calculation.The MotionEC library works perfectly fine but I ran into troubles with the MotionMC library.At first, I'm running the MotionMC_Update function with the parameters I'm reading from the Magnetometer. After that, I'm calling MotionMC_GetCalParams to get the calibration parameters. But the library is always returning the following default values:HI_Bias = {0, 0, 0},SF_Matrix = {{1, 0, 0}, {0, 1, 0}, {0, 0, 1}},CalQuality = MMC_CALQSTATUSUNKNOWNHere is my code (based on the ST examples).// COMPASS_REPORT_INTERVAL = 20// gets called every 20msvoid doCalibrationStep(){    SensorAxes_t mag_data_uncompensated; &n

HelloDoes anyone know the signal Oversampling Rate/s?I'm working for a Medtech company developing a novel device and we are thinking of using the LIS2MDL for our analysis. The data from the sensor will be analysed using different signal processing techniques such as FFT etc.we would like to know the sample rate to assess whether LIS2MDL sensor is compatible with our requirementsThanks    Thank you 

Hi all,This should be a question with a simple answer, but for some reason, I cannot find clarification. I am trying to use the Finite State Machine in the LSM6DSOX, and I have come across these examples below in this application note:I'm confused on how to determine the THRESH1 values that are in the programs above. From what I read, the FSM uses the same linear acceleration sensitivity value as is output to the host MCU. As an example, my understanding is that I would take 3C66 (from program 2) as the number of LSBs, multiply that by the linear acceleration sensitivity value (i.e. 0.061 mg/LSB for FS = +-2g) and then that would be how you get the 1.100g that is in parenthesis. Doing the actual math with the different linear acceleration sensitivities for the different FS values, I don't find any of them equating the 1.100g.I can't find any other information on how to convert the desired acceleration value in gs to the values provided to the FSM THRESH1 like is shown in the above

HeyLSM6DSV16B is sold as an accelerometer unit that can be used to record vibrations as an audio signal. The datasheet mentions that this audio signal can be placed on the TDM interface, but I doesn't really say how.Does anyone have experience with this product? Is there already a code library for using this device for audio?

Hi everyone, some of my initial issues have been solved while one is still remaining. Most Bluetooth 5 devices cant connect to the Bluetile sensor node. I have to use the programmer board with the sensor node on it connected via USB to establish a bluetooth connection. This fails with most BT5.x Laptops: 1 ASUS, 1 Lenovo, 1 Dell and my Fairphone 5. Sometimes pairing works with an ASUS Bt5.0 USB-dongle but sometimes connects and sometimes doesn't. E.g. the node has rested for about 5 minutes in battery mode and has (magically) connected. This seems very random and is the same problem as with the second Bluetile node we are using. The figure shows the deactivated Intel BT4.x Adapter. The sensor node is represented by the 2 black question marks. While connecting via BT4 it says BCN002. In Bluetooth menu it always says BCN002.. I can connect via Intel BT4.x and ASUS BT4 USB-dongle. Is the stock firmware unable to work properly with BT5.x? Thanks for reading th

Hi,I'm looking for the information about the number of sensor ADC samples per output data, in low power mode Vs. the high resolution mode.I found the following description in AN5069:"The difference distinguishing the two modes is in the number of samples used to generateeach output sample, which is four times less in Low-Power mode than the number used inHigh-Resolution mode, thus ensuring a lower power consumption"However, I didn't found what the actual number is.Thanks,Dagan

I am looking to design board with LIS3MDL (Mag) with ICM42688(Acc and Gyro) snd MS5611(baro) on single board with single SPI bus through different CS for all IC's. However for LIS3MDL the CS is used to switch between I2C and SPI interface. 1. Will the design work with all these 3 ICs on same SPI bus.2. Will the LIS3MDL IC start driving signal on SDI pin(considering it as I2C command) when CS is high for it and low for other IC.3. can multiple LIS3MDL on single SPI bus possible with different CS.   

Hello, "1/ODR (1 à 200 HZ)" is it the response time of the sensor ?Thank you 

Hello,What is the supply current into the VDD_IO pin on the AIS2IH? The VDD supply current requirements are explained in detail, but I do not see any note on the current into the VDD_IO pin.Best regards

According to AN5192 (last paragraph of page 50) if LIR is enabled (0x56:0x4F)  and SINGLE_DOUBLE_TAP is set (0x5B:0x80) "latched mode is applied to the double-tap interrupt signal only".But I only read single tap in TAP_SRC (0x1C:0x20) during ISR.As soon as I disable LIR I get both interrupts.Is there an error in AN5192 and only single tap will be signalled when LIR = 1?Or I made a mistake somewhere in the registers?Here is my register dump:# i2cdump -yf 1 0x6a 0 1 2 3 4 5 6 7 8 9 a b c d e f 0123456789abcdef 00: 00 00 3f 00 00 00 00 00 00 00 40 00 00 08 00 6c ..?.......@..?.l 10: 60 28 44 08 60 00 00 00 e2 20 02 0f 00 20 07 28 `(D?`...? ??. ?( 20: b3 01 0d 00 ee ff f5 ff b2 01 23 00 63 41 00 00 ???.?.?.??#.cA.. 30: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 40: cd 05 20 00 f3 05 20 00 00 04 00 00 00 00 00 00 ?? .?? ..?...... 50: 00 00 00 00 00 00 4f 06 86 06 8a 80 00 00 4a 00 ......O?????..J. 60: 00 00 00 fd aa 01 00 00 00 1a 21 21 40 06 00 00 ...???...?!!@

Hello All,is it normal that the data in the offset calibration registers disappears after a power restart?  

Hi,From the following repo https://github.com/STMicroelectronics/st-mems-android-linux-sensors-hal/tree/masterI would like to know if the driver it's compatible with an Android environment under snapdragon where all the sensors part is managed under the ADSP and the SSC core library. On this systems the sensors part is managed trough the SSC Framework who handles the sensor core functions.Does anyone have experience with it or know if it is compatible?Thank you.

Hi there,I've recently been exploring the BL4S5IIOT01A board and successfully followed the documentation provided https://catalog.us-east-1.prod.workshops.aws/workshops/b5857416-f2f6-4188-8562-053ec5f983ef/en-US to learn how to connect the board to IoT services using its built-in sensors. Now, I'm interested in creating projects that involve custom sensors on this board.Could you please provide documentation or guidance on how to build projects from scratch, integrating custom sensors with the BL4S5IIOT01A board?Thanks in advance!

Hi, I want to receive data coming from the sensor without loss.For the testing, sampling rate is set to 32Hz.26667(ODR) / 800 = 32hzif set like this, 32 data per second will be accumulated in the buffer.and CNT_BDR_THR was set to 100.also, FIFO_MODE was set to continus mode.I am reading data by checking counter_bdr_ia as shown in the code below.My expectation is that counter_bdr_ia should occur approximately once every 3 seconds, but counter_bdr_ia is occurring faster than that.Please let me know what's wrong. Or please give me an example for reading without data loss.  Spoiler (Highlight to read)uint16_t fifoDataCnt;iis3dwb_fifo_status2_t countFlag;static uint32_t time_count = 0;while(1){time_count = XTHAL_GET_CCOUNT();iis3dwb_fifo_data_level_get(&dev_low_ctx, &fifoDataCnt);iis3dwb_fifo_status_get(&dev_low_ctx, &countFlag);if(countFlag.counter_bdr_ia == 1){printf("Buff chk Before %d %d counter_bdr_ia %d \n", time_count, fifoDataCnt, countFlag.counter_bdr