MEMS and sensors

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

Posted on September 26, 2016 at 23:15We enabled GyroScope and acclerometer. We set FIFO Mode to continuous with BDU bit is set. We set ODR rate to 1.66kHz . We are reading FIFO continuously. we are observing FIFO data mis-alignment Can somebody help on this? #lsm6ds3-fifo-alignment

Posted on February 04, 2017 at 03:36Hi,   We are developing a ultra low power sensor module with the LSM303D. The LSM303D was periodically waken up to take a  magnetic and temperature measure (no acceleration measurment). The total excepted average current is <100uA, but the acture current is >300uA which was unacceptable.   The following picture was snapped from the oscilloscope measuring the module's current. The narrow pulse current were caused by the module's periodically magnetic and temperature measuring activity. But the ramp shape pulses were unexpected. Sicne these ramp-pulse lasts for hundreds of miniseconds each, the total current was dramatically increased.   The questions is:   Are these ramp-pules current normal for the LSM303D?

Posted on January 17, 2017 at 19:16Hi.I am using the LSM9DS0, and have observed a lot of noise on the z-Axis of the Accelerometer Data. The attached picture is a plot showing the noise while operating at 100Hz in the +-2g range. Is this a normal level of noise for this device, or am I doing something wrong, or is the device defective?kind regards.Erich Neumann#lsm9ds0 #accelerometer #noise

Posted on March 26, 2015 at 14:53 Hey there, I recently installed a new LSM303D (accelerometer + compass) on my board and I am having some issues with it. I can read the data from the accelerometer fine, but the ones from the compass seem ''locked'', I read a total of 3 pairs of MSB-LSB, of which only the LSB change over time. Here is an exemple of reading (LSB on the left): Mag X: -125 -1 Y: -93 -1 Z: -22 -1 Mag X: -115 -1 Y: -101 -1 Z: -26 -1 Mag X: -119 -1 Y: -78 -1 Z: -34 -1 The LSBs change erratically regardless of the orientation of the sensor. Here is the config I'm using: ST_CTRL_REG 1 , 0 x 67 ST_CTRL_REG 5 , 0 x 60 ST_CTRL_REG 6 , 0 x 00 ST_CTRL_REG 7 , 0 x 80 I am using SPI. I don't really get how I am not getting the values right. Any help or lead would help me a lot :) Thanks !

Posted on October 26, 2016 at 16:43Hi , I have STEVAL WESU module  and logged acelerometer data using android app. (plz see attached file)My settings are: Timer: 512 Hz, 10Hz, 1HzMEMS Accelerometer output data rate: 416 Hz , 833 Hz, 100HzIn the logged data host time stamps and node time stamps are available. My  observation:All the time stamps are in milliseconds.Host, stamp time on data at 100Hz if Timer value > 100Hz otherwise at Timer value. Node, stamp time on data at 1000Hz irrespective of ''MEMS Accelerometer output data rate'' settings. If Host time stamp rate  lower than node time stamp,  then are we losing data? What is allowable max. data rate at which we can log accelerometer data considering BLE protocol? As per sensor data sheet 1Hz- few kHz data rate is allowed. thank you,  #steval-wesu

Posted on January 31, 2017 at 06:12hi,     I am Reading the Accelerometer and Gyroscope sensor values by checking the XLDA and GDA bits as follows             if((readReg(STATUS_REG)&0x01)==0x01)     // checking XLDA        {              Ax = (int16_t) readReg(OUT_X_H_A) <<8 | readReg(OUT_X_L_A);              Ay = (int16_t) readReg(OUT_Y_H_A) <<8 | readReg(OUT_Y_L_A);             Az = (int16_t) readReg(OUT_Z_H_A) <<8 | readReg(OUT_Z_L_A);       }if((readReg(STATUS_REG)&0x02)==0x02)        // checking GDA { Gx = (int16_t) readReg(OUT_X_H_G) <<8 | readReg(OUT_X_L_G); // typecast as Gy = (int16_t) readReg(

Posted on January 27, 2017 at 15:04Hello, sorry for me level in EnglishI have to carry out an end of year project of electronic bts, and I am stuck at this levelI need your help to understand a lack of reading in the following code I use this soft : 'Sensors_Reader', it is a program provided on the page of the site MBEDI have this board NUCLEO_L476RG and this shield sensors 'X-NUCLEO-IKS01A1'I receive this information in return on 'un moniteur serie' :--- Starting new run ---Humidity | Temperature Sensor ID = HTS221 (0xbc | 0xbc)Gyroscope | Motion Sensor ID = UNKNOWN (0x0 | 0x0)===I2C [errors]: 0x00       X                Y                ZMAG [mgauss]:     &

Posted on January 27, 2017 at 00:19We were looking at using the LSM6DS3 in a new design, but I noticed the LSM6DSL uses half the power.  The two parts look to be pin compatible and probably software compatible (at least for most features).  Is that correct? More specifically: is it valid to use the AN4650 Application note to work with the LSM6DSL (at least until there is a similar application note for that part available)?  Is it likely that code written for LSM6DS3 would work if the part were swapped with the LSM6DSL?Any ETA on a usage application note for the LSM6DSL?#lsm6ds3 #lsm6dsl

Posted on January 25, 2017 at 05:13x = ?y= ?z = ?

Posted on January 24, 2017 at 14:28

Posted on January 04, 2017 at 00:05I am interested in viewing compass heading ( from north) out of the WeSU1 dev kit. Is this merely a setting within sensor fusion to obtain this?Thanks!

Posted on January 23, 2017 at 18:13The spec for the LIS3DSH quotes +-16g, yet the sensitivity at full scale is 0.73mg/LSB, giving a full scale range of +-24g. Can the sensor be used effectively at +-24g? What kind of non-linearities or other errors might arise at these higher levels?

Posted on January 23, 2017 at 13:03Hi,     I am using STEVAL-MKI160V1 evaluation module of LSM6DS3 in arduino platform with 8g scale.  When I turn this 1g to -1g , it suddenly fall to 89 , 86 , 89.......etc ,  from 4173  (1g reading, that i got)  with a tilt of less than 5 degree from initial position , ie the g value varies not sinusoidally. it gives some valid values in some other positions between a rotation of 1g to -1g, and again falls to invalid values mentioned above,  Due to this my Madgewick filter give me , error output. Attaching my codes , Please help to solve this problem

Posted on January 16, 2017 at 18:26I am trying to configure the iNemo to assert INT1 when significant motion is detected. I have followed AN4650 closely (the configuration matches that given in AN4650 Section 6.2 at the end of the section), but no interrupt is ever generated. I am using a STEVAL-MKI160V1 plugged into another board. I'm probing INT1 on the STEVAL while shaking the board and otherwise trying to simulate walking, running or other motion. I have tried reducing the threshold, including DEB_STEP, but nothing has worked.Does this mode actually work as documented? Do other registers need to be written to make this work? I have the FIFO turned on, and it accumulates data at 26Hz as expected.Thanks.

Posted on July 27, 2016 at 20:51I'm just getting started with the CCA02M1 expansion board, Nucleo '476RG and X-CUBE-MEMSMIC1 software.I've got the software compiling in Kiel, and the USB-audio interface works well.(44.1kHz sampling doesn't seem to work properly, though 16 and 48kHz are fine. The documentation is a bit ambiguous regarding support for 44.1kHz, but that's not a big deal at the moment.)My question is that the demo software uses 1 millisecond buffers and this is pretty hardcoded - with many instances of (samplerate/1000) and variations of that in the codebase.I'm interested in performing signal-analysis on buffers of exactly 256 or 512 samples (which will be around -but not exactly- 10ms in duration).Is there any special reason why the buffers have been kept so small, and/or the buffer size isn't more parameterised?(I don't require USB streaming for this application, although it migh

Posted on December 13, 2016 at 04:27hi, allI want to enable STEVAL-MKI119V1 on Windows platform, but without an available software. I contacted the STMicroelectronics Support team, but they told me that product STEVAL-MKI119V1 is obsolete, they do not retain any information or data on obsolete products. Fortunately, they also told me that there are also online distributors that still have in-stock inventory, so some will still have access to information and documentation concerning this product. That's why I come here. If someone could help would be very appreciated.  BTW, if someone could help propose an alternative product that have the he same capabilities with STEVAL-MKI119V1 would be great. My purpose is to find an available device which has the ability to access sensors(Ambient Light, Gyroscope, Ac

Posted on January 14, 2017 at 07:28My suppliers in Australia say it is obsolete and Mouser quote 20 weeks delivery. Digikey show no stock and I cannot get an availability. ST website says it is active. Can someone recommend an equivalent to this. I need to get hold of 25 of these now and a further 150 in 3-4 weeks time. 

Posted on January 09, 2017 at 10:41I would like to use an iNemo with an external magnetometer (i.e. Sensor Hub mode) to gather data and place acc, gyr and mag readings in the FIFO. Is it possible to have the mag drive the ODR of the iNemo with its data ready line?The mag data is the most important, and it would be nice to collect data at its max ODR of 220Hz. The iNemo supports rates of 208Hz, 416Hz, and so on. I would prefer to avoid rates where I get duplicates or dropouts in the mag data.Thanks.