MEMS (sensors)

Posted on February 23, 2017 at 08:04Hi all,I'm playing with the LSM6DSL sensor on the IKS01A2 board.I'm trying to use the FIFO to record and buffer accelerometer and gyro data.The accelerometer works fine and reading the gyro registers directly gives sensible data, however the gyro data in the FIFO for all 3 axes is *always* 0x7FFF (ie MAX_INT for int16_t).I have scoured the datasheet and the LSM6DSM application note and can't find any indication of why this might be happening.I've tried a huge amount of various settings, with no difference in outcome, currently using:X_ODR = G_ODR = FIFO_ODR = 416HzDecimation = 1 (no decimation) for both accelerometer and gyro.Typical FIFO readout looks something like this:...Got pattern    0 value 32767 (0x7fff) from FIFO with    6 words (empty=0 smartfull=0 overrun=0 watermark=0)Got pattern    1 va

Posted on November 07, 2016 at 11:56Hy,for a proof of concept I created five identical devices, each having 3 VL53L0X, so I have an overall of 15 VL53L0X that are mounted (behind an acrylic glass shade) and connected (via 2.8V, I2C) identically. During test of my devices I observe, that one of the sensors has quite exact the half sensitivity of all other devices: amplitude is about half, standard deviation is about four times of the other sensors.I can't see any optical explanation for this: no scratches nor soiling of the front glass. Might there be any other explanation? Do I need to characterize devives before I use them?RegardsHarald #vl53l0x #sensitivity

Posted on February 23, 2017 at 07:54The error says 'Symbol rotAcc multiply defined in osx_motion_pe.o and osx_motion_id.o'. But there is no such symbol in both their header files. I am trying to execute the MotionPE and MotionID libraries provided by STPlease HelpRegardsNitish#library #stm32l #motion #libraries

Posted on February 22, 2017 at 02:00I have went to just order the H version and found there is none left. Anywhere. So then I started looking and the US version is on stock. All the specs look identical but I just want to know for sure. Any help or insight would be great. Thanx

Posted on February 22, 2017 at 07:25Sensor tile (stm32l476jgy) hangs when trying to access osxmotionPM library without delay.Please Help...#stm32l4 #mems #pedometer

Posted on February 22, 2017 at 07:13On same set of code on sensor tile, the accelerometer some times outputs the data and sometimes it didn't on same set of code.main{BSP_ACCELERO_Init(ACCELERO_SENSORS_AUTO,&acc_handle1)   BSP_ACCELERO_Sensor_Enable(acc_handle1)while(1){      BSP_ACCELERO_Get_AxesRaw(acc_handle1,&acc);}please help with this...

Posted on February 21, 2017 at 18:22Hello,in wesu downloads I can find ResetManager, UsbDfu and OtaDfu applications in bin format.Are they available also in source format?Thanks in advanceFabiano

Posted on February 13, 2017 at 16:04HiIm having the device VL53L0X which I want to communicate with trough the I2C protocol to my STM32F401RE micro controller.Im using CubeMX from STM to setting up the pins which works fine, but I don't know how I 'connect' the I2C functions from the API with the I2C at the MCU.As far as I can read in the VL53L0X API Specification, something in the 'VL53L0X_platform.h' has to be adapted to the platform but Im not sure how to do it. Can somebody give me an example, and also point out what I has to change?Best regardsS�ren

Posted on November 11, 2016 at 10:45I always get the error 0b0111 (max convergence) if I make a range single shot measurement (I also don't know if other modes are working). I tried to disable the ECE but still the same. I tried it with the code from the ''VL6180X range and ambient light sensor quick setup guide''. Can anyone help me to get this working?Regards Simon #vl6180

Posted on November 21, 2016 at 11:22Because of the limitation, my project just can use 16bit MCU to drive VL53L0X. The API of VL53L0X is too complex and not suitable for 16 bit MCU, so I can't just  use the API directly...It is very time-consuming for simplifying.... #vl53l0x

Posted on February 20, 2017 at 08:57Hi,I am using LIS2DH in our custom board and I am trying to detect some scenarios using this accelerometer. I read the datasheet and application note and tested almost all features. But I'm not sure how to apply them to my scenarios. The sensor is connected to my device which is attached to an underground waste container. The accelerometer can not detect constant speed. So I can not know if the waste collection vehicle is lifting it up(assuming it is lifting it on a constant speed).  All I can do is detecting the transition between the device's stable position and the first movement using the free-fall interrupt on the Z axis.Is there any chance to differentiate the situation of my device between the stable and getting lifted on constant speed? Is there any article about collecting the accelerometer data for such scenarios?#teft #detect #lis2dh #accelerometer #lifting

Posted on February 13, 2017 at 17:37Hello I don't understand why I get value  aroung 1.3 Gauss ?Configuration :   LIS3_CTRL_REG2 = 0x00;   // Full scale +/- 4 G   LIS3_CTRL_REG1 = 0x1C;   // ODR=80Hz, XY LowPower   LIS3_CTRL_REG4 = 0x00;   // Z LowPower   LIS3_CTRL_REG3 = 0x00;   // Continuous-conversion mode   LIS3_CTRL_REG5 = 0x40;   // BDU = 1and I receive :   LIS3_OUT_X_L = 0xEB   LIS3_OUT_X_H = 0xEE      => MagX = 0xEEEB = -4373   LIS3_OUT_Y_L = 0x94    LIS3_OUT_Y_H = 0x07 => MagY = 0x0794 = 1940  &

Posted on August 25, 2015 at 13:12​Hi,I working with Barometric Pressure sensor LPS331AP.Its working good. but as this chip absoluted,then we changed design to LPS25HB.But this chip is reading 6.4mBar error apart from the actual measured value .We are not added any offset value and not done any our factory calibration.Just I reading the 24-bit data and displaing converted pressure.I did 't change any code,just I replaced LPS331AP by  LPS25HB chip.Advice me is it nesassary to change any code ? or any calibration or offset vaules need to set?/Please advice us...

Posted on February 08, 2017 at 21:16Good afternoon,I am trying to determine the theoretical accuracy of an angle calculated with the lsm6ds3 accelerometer.  From the spec I see there are a number of sources of inaccuracy/noise.  There is noise density that is dictated by range and sampling frequency, zero point change due to temperature and zero point accuracy.  Of these, zero point accuracy is listed as a constant value of +/- 40mg.  There is no mention of any factors that can be used to change this value for the better (e.g. lowering the range reduces the noise density).When we determine the angle we use the arctan of two of the readings.  For the 45-degree worst case that means we would get a theoretical measurement of x = 0.707g and y = 0.707g.  If I assume worst case zero point accuracy only on both of these values (+/- 40mg), one positive and one negative, I get x = 0.747 and y = 0.667.  That gi

Posted on February 16, 2017 at 23:37hello,we are using H3LIS331DL to record shock on our instrument.we have setup INT1 to interrupt when acceleration>threshold.when the interrupt occurs we read out values and store it.we have observed that sometimes we read out acceleration that is less than threshold.why is this happeningPradeep#authentix #h3lis331dl

Posted on February 16, 2017 at 15:48I am looking at the data sheet for the M24M02 and I want to read the Lock Status.  The data sheet says thisThe locked/unlocked status of the Identification page can be checked by transmitting a specific truncated command [Identification Page Write instruction + one data byte] to the device. The device returns an acknowledge bit if the Identification page is unlocked, otherwise a NoAck bit if the Identification page is locked.If I send the ID Page Write instruction plus one data byte, won't that actually write the data byte if the ID page is not locked?Or does this mean to send the Device ID byte plus one byte (which would be the first address byte in a real write command)?Thanks for your help.Tom

Posted on February 14, 2017 at 23:24We are evaluating the LPS25HB BP sensor, and have a couple of questions. I notice that several forum members have asked similar questions, but without receiving a reply. I would really appreciate an answer, as this would indicate that the LPS25HB is not an 'orphan', unsupported product.1) The datasheet mentions a soldering effect on BP, and says that a register is available to store a one-point calibration. There are no other details at all about this in the datasheet. We have found substantial (~0.5 kPa+) pressure inaccuracy in samples we have tested. Is this to be expected? Exactly how are we to use the calibration register? How is it calculated? Again, these are important points for any user, and the datasheet gives no meaningful information.2) We notice a very substantial temperature effect on BP. It appears that no temperature compensation is being done internally to the chip, although the datasheet

Posted on February 14, 2017 at 13:03Hi all,I have got a technical question, if is possible to get some helpful feedback, I would really appreciate it, please.I have recently purchased a LIS2DH12 accelerometer and I am plugin it within a Teensy module in order to check the right behaviour. I have only enabled �Z�axis by 0x20 and 0x30 registers.  However, my Arduino console also shows me that �X�and `Y` axis are enabled throughout the 0x31 register. So, my question is: Which registers should I configurate and keep in mind for just activate �Z�axis?Well, my Register configuration is the following one;while(i2cWrite(0x20, 0x34, true)); while(i2cRead(0xA0,i2cData,1));Serial.println(i2cData[0],HEX);while(i2cWrite(0x22, 0x40, true));while(i2cRead(0xA2,i2cData,1));Serial.println(i2cData[0],HEX);while(i2cWrite(0x23, 0x08, true)); while(i2cRead(0xA3,i2cData,1));Seri

Posted on February 10, 2017 at 20:05The LSM9DS1 datasheet does not give a good description of the DEN_A/G pin.  Can someone add value to this?  Should it just be pulled high and never toggled by MCU?  Reference schematics of part from Sparkfun, etc. show the SDO output of the Magnetometer and Accel/Gyro are tied together.  My intuition thinks the pin is tied to an internal tri-state buffer and should be toggled to avoid the data contention between the two hardware machines (Mag and Accel/Gyro)ThxSteve 

Posted on December 20, 2016 at 15:52hi all,     I have recently purchase a WESU1 device and used it as a reference for my custom wearable device design. i re flashed the WESU1 device with the sensor example firmware(STSW-WESU1) found it from following ST link and the file location '/external-link.jspa?url=http%3A%2F%2Fwww.st.com%2Fen%2Fevaluation-tools%2Fsteval-wesu1.html'  'en.stsw-wesu\STSW-WESU1\Projects\STEVAL-WESU1\Examples\Sensors_Read\MDK-ARM' I used keil to compiler and debug the firmware and found out that the system tick handler stopped while configuring the External clock.     I tried configuring WESU1 (stm32L151VEY6) to toggle a LED on-board using stm32CubeMX with the fresh project and the external clock configuration has no issues related to the system tick handler. i perform this to check the Hardware functionality and look for any hardware rel

Posted on October 28, 2014 at 19:50I would like to know if bringing up both the Vdd_IO and Vdd lines at the same time on the LSM9DS1 is hazardous for the unit or problematic for its functioning. Why must the rails be brought up in sequence and what problems might I face if I bring them up at the same time?I have a slew rate controlled switch, but my lines to Vdd_IO and Vdd are tied together. Before I do the board rework I was curious what problems I might see if I simply brought both lines up at the same time. Any insight is much appreciated. #lsm9ds1

Posted on December 01, 2016 at 12:40I am having trouble getting the click interrupts to work for the LSM303D. using the library provided by Pololu for arduino I can get this code working for the DLHC[code]#include <Wire.h>#include <LSM303.h>long thisLong = 0;LSM303 compass;const byte interruptPin = 2;void setup(){  Serial.begin(9600);  Wire.begin();  compass.init();  compass.enableDefault();    compass.writeAccReg(LSM303::CTRL3,     0b11000000);  compass.writeAccReg(LSM303::CTRL0,     0b00000000);  compass.writeAccReg(LSM303::CLICK_CFG, 0b00010000);  compass.writeAccReg(LSM303::CLICK_THS, 0b00011111);  compass.writeAccReg(LSM303::TIME_LIMIT, 0b00011111);  delay(100);  attachInterru

Posted on October 06, 2014 at 20:30Hello, I would like to prototype a conference room microphone. Is the MP34DT01 mic able to capture sound from a human speaker away from 3 or 4 meters ? (ex: classroom) If no, what would be the recommended mic ? In this video https://www.youtube.com/watch?v=D-o9dQCegiA, the speaker seems to need to be close to the array of mic. Also, to filter out the ambient/background noise and perform 3d localization of the sound source, is the STA321MP audio processor the correct choice ? Thank you, Pierre #mems-microphone #steval-boards-for-mems-mics

Posted on December 13, 2016 at 01:06Hi All, I am developing device to analyze vibration with LIS2DE12 acceclerometer.I have encountered problem that sensor did not work with ORD=5.3kHz, it worked fine for all other ODRs.How to configure sensor to work ODR=5.3kHz ?My configuration is as followsCTRL_REG1 : 0x97CREL_REG3 : 0x10 CTRL_REG4 : 0x10All other registers are default. My expected processing steps are as follows1. INT1 pin is enabled when sensor data is ready2. MCU got INT1 signal, send event to handle interrupt3. interrupt handler read sensor data.As I have measured, the period of INT1 signal is around 1.3kHz please take a look at my configuration and let me know anything to check. Regards,Hae Ryong

Posted on May 09, 2016 at 13:05hi, I've got a few questions. 1. what is the order anti-aliasing filter of the Acc? 2. what is the order anti-aliasing filter of the Gyro? 3. how does the DLPF1 filter help me if the cut-off freq is higher then nyquist freq? thank you, amir #lsm6ds3 #lsm6ds3