MEMS (sensors)

Posted on March 28, 2017 at 20:03LSM303AGR how to enable high resolution mode on the accelerometer? I have done exactly as described in the data sheet/manual setting the LPen bit to 0 and the HR bit to 1. I can play around with these bits but it does not look like I get a change in the resolution. The data written out by my program matches exactly the data bytes shown on my oscilloscope (with serial SPI decoding). The 6 least significant bits are always 0. Setting the BLE bit does not swap the order of the bytes which indicates that I am not able to activate the high resolution mode (BLE only works in high res mode). Anyone who can help here, what is the trick to get 12-bit resolution on the accelerometer?My register settings:- CTRL_REG1_A set to 0x67 ( ODR 200 Hz, LPen = 0, all 3 axis enabled)- CTRL_REG2_A set to 0x00 (high pass stuff disabled)- CTRL_REG3_A set to 0x02 (FIFO overrun int on int1)- CTRL_REG4_A set to 0x8

Posted on March 27, 2017 at 18:19Hello, I am currently working on the STEVAL-STLKT01V1 development kit and I would like to use the sensortile to give an analog output in order to activate a motor. Does anyone know which of the output pins of either the sensortile or an expansion board I could use to get a >3V step?Thanks

Posted on March 22, 2017 at 14:37Hi.I've got the WESU1 unit and I was wondering if it was possible to collect the MEMS data via bluetooth into an Arduino for processing.Has anyone done this before?Thanks.

Posted on March 21, 2017 at 23:05Hello,I am trying to operate the VL53L0X through ADLINK I2C SEMA3.5R7 (com express) interface.I initialized all the registers correctly according to - https://github.com/pololu/vl53l0x-arduino/blob/master/VL53L0X.cpp after around ~1 min of use(continuously read the 16bit from 0x13) the device halts, i get 0 on all of the readings from the device and the only way i can get the results back are to initialize the device again.Is there any error code register to get better understanding why the device freezes? Is there any chance that someone had same issues with this device?I am using the satellite with 10K pull-up resistors on SDA/SCL.Appreciate your help,Itamar#vl53l0x

Posted on July 27, 2015 at 18:07 Hi ST Community! I am working with LPS25H pressure sensor and STM32F1 uC. I am able to read out temperature and pressure but the pressure value is too low (temperature is fine). It should be 15 mbar and the sensor outputs 94 mbar. I have tried adding pressure offset value after soldering, but the pressure is then 12 mbar. Does anyone have any clue what should I be carefull about? Initialization and read routines: INITIALIZATION // RES_CONF 0x05 I2C1_numData = 1; I2C1_buffer[0] = 0x05; I2C1_Send_Data(I2C1_buffer, PRESSURE_ADDRESS, 0x10 | 0x80, &I2C1_numData); // CTRL_REG1 0xC0 // CTRL_REG2 0x00 // CTRL_REG3 0x00 // CTRL_REG4 0x00 I2C1_numData = 4; I2C1_buffer[0] = 0xC0; I2C1_buffer[1] = 0x00; I2C1_buffer[2] = 0x00; I2C1_buffer[3] = 0x00; I2C1_Send_Data(I2C1_buffer, PRESSURE_ADDRESS, 0x20 | 0x80, &I2C1_numData); // FIFO_CTRL 0x00 I2C1_numData = 1; I2C1_buffer[0] = 0x00; I2C1_Send_Data(I2C1_buffer, PR

Posted on March 20, 2017 at 13:40Hi, I am using H3LIS200DL with RFduino (RFD22102 ) as microntroller, I have used the schematic given in data sheet except I have connected CS pin to Vdd (for using I2C). Also I am using Arduino H3LIS331Dl_demo code attached below.The IC works fine for 5mins and then readings become constant. And when I use it again after 10 hours or so, it again works fine for 5mins only. This is happening from 3 days. I have also resoldered it and rechecked the capacitors. I used 3 ICs. One worked fine but the same problem is happening with other 2.Is this any soldering problem?Am I missing any point?Help would be appreciated.H3LIS200Dl data sheet : http://www.st.com/content/ccc/re

Posted on March 16, 2017 at 17:50I have a MKI72V1 adapter board. On Unico with V5 it does show up on the devices list however when I select the device I get an error message saying the device is not supported by the motherboard. Please advise.#mki172v1 #lsm303agr

Posted on March 17, 2017 at 11:24I am Designing a MEMS base capacitive moisture senor and now i am stuck with the design of inter digital electrodes (number of electrodes , width,length,gap between the fringes)

Posted on October 04, 2016 at 15:22Hi.I'm testing LSM303AGR. If I put my sensor module on the my desk, Z value of accelerometer's output is about 1400 LSB. I'm using high resolution mode(12bit) and 16g range. If I calculate this value as mg unit, the output value is calculated as 16,408mg. I expected the output value about 1000mg(Gravity), but the result is quite different. Could you give me some comment about the resolution of this sensor?  #lsm303agr #resolution.

Posted on May 12, 2015 at 00:19I have the STEVAL-MKI109v2 MEMS evaluation board and an STEVAL-MKI161V1 MEMS sensor for the board to evaluate a gyroscopic accelerometer. On the STEVAL-MKI161V1 web-page on st.com it shows that this board is compatible with the MKI109V2 board, which is fantastic... EXCEPT! The Unico GUI software doesn't list this as a supported device in any of the device type designators. I haven't been able to get a quick communication to the device to prototype with the sensors measurements...Anyone experiencing the same issue? Any work arounds?

Posted on March 15, 2017 at 11:21Hello,In my application I use a SAFT lithium battery (LS 26500). I'd like to detect it's end of live by measuring voltage value. The voltage value depends on current and temperature.So, I'd like read the temperature from the accelerater sensor on my board.The problem is that I saw this thread : https://community.st.com/message/132806 If I understand, the temperature value is not absolute. So, my question is :    - How do I calibrate the temperature sensor ?   - What is the conversion factor to get the right temp value?Thanks,Julien.

Posted on March 14, 2017 at 18:34I have a MKI178V1 attached to the MKI109V2 evaluation board.  When I go to collect data using the Unico GUI, my adapter board is not on the list of devices. Can I add my device somehow?

Posted on March 13, 2017 at 01:49All the sensitivity values for the acceleration fit within 16 bits, however  �16 g does not.Let�s use FS �2 g as an example sensitivity level.  As the range is -2 to +2, this would be a total of 4g.  Or 4,000 Milli-Gs.The output is 16 bits. 16 bits equals 65,535.   This means we can get 65,535 different readings for the range  between -2 and +2. (or -2,000 MilliGs and +2,000 MilliGs)4,000 MilliGs / 65,535 = 0.0610.061 is what is seen in the datasheet for �2 here are the values for all sensitivity levels;�2  = 4,000 M

Posted on March 13, 2017 at 07:59We have installed the VL53L0X onto one of our drones and noticed that the sensor will give 8191 or 8192 in millimeters for range measurements frequently when the drone is placed outdoors. The actual height information will be in the readings, but cannot be used as there are also many out-of-range readings. Once we move the drone indoors, the 8191 or 8192 mm readings appear. We tried to use the high accuracy mode but the issue does not go away. Can we safely say that this sensor is not suitable for outdoor use? 

Posted on October 13, 2016 at 12:48Hello all,We are planning to include a PCB in a little tunneling machine in order to measure inclination and deviation (in degrees) in relation to an origin (0,0,0). We are looking for a sensor, maybe a gyroscope, but the selected sensor must be robust against vibrations and magnetic fields. Anyone has a trace about which sensor should we use? Maybe MEMS is not an option? Thanks in advance. #gyroscopes #inclinometers

Posted on March 09, 2017 at 20:13Hi fellows,on setting up an LIS2DH12 I wonder what settings to use for those registers:CTRL_REG2:HPCF1/2: couldn't find this in the datasheet...CTRL_REG5:How shall I enter '- -' ?And what's gonna happen with D4D_INT1?I got the impression that this value is to read, not to write...CTRL_REG6:Again, some '- -' values without comments...We're not gonna use the INTs (at the moment).

Posted on November 12, 2016 at 20:14Hello, currently I can't download the API STSW-IMG003. Indeed when I choose get software ==> download, I'm rediricted towards the home page: https://my.st.com/content/my_st_com/en.html#.What about this issue ? Somebody could download this API ?

Posted on March 01, 2017 at 21:45Hello all,    I want to modify the sensor i2c address. So, i can use more than 1 VL53L0X Sensors.I see AN4846. On page 5/7 it mentioned for API integration guide which is UM2039. In API guide (UM2039), page 20/26 6.6 mentioned for I2C address. Question is: How to program the VL53L0X ?                    What development board, i have to purchase ? Eventually, i want to use multiple VL53L0X with non-stm processor. Thank You in advance !Swapneel

Posted on February 17, 2017 at 11:04ST politics about VL53l0X Hy ST,in a customers project I deal with the VL53l0X quite a bit, we have a nice prototype up and running and are about to decide if we want to start designing a series device.Ever once in a while I look into this forum and follow the discussion about the device and come to the conclusion, that ST is not very willing to provide further informations about the insides and usage of the device.The thread https://community.st.com/0D50X00009XkeHcSAJ nails it down very nice.Can anyone of ST maybe give some information about the politics around VL53l0X? Will there be a better support of the device in the future? Is it running in high volume already? Was it designed for one target application and no other user or project is supported? We probably must take the response to these

Posted on March 01, 2017 at 08:30Hi,In the 'Examples of output data' section of the LSM6DS33 application note AN4682, there are tables showing examples of the output register values and the corresponding acceleration and angular rate values for a given scale. Can you please elaborate how the values are calculated?Regards,Prachi #lsm6ds33 #accelerometer #gyroscope

Posted on February 26, 2017 at 23:32Hello.I´m having problems on SPI reading WHO_AM_I register of a LSM9DS1 mounted on STEVAL-MKI159V1 : the correct answer is 0x68 but very often I got 0x28. The suspect that the level of bit 6 was not correctly set is confirmed by some traces of the oscilloscope but I need to say that:1) Attaching probes fixes the problem : for some reasons the loads of probes solve the problem.2) I got the two attached pictures during the initialization of the board or shaking a little bit cables of a second circuit on a breadboard.  Summarizing the situation : in normal condition I got very often the incorrect value 0x28 but when I connect probes the problem disappears and I have always the correct value 0x68. Only in some conditions - initialization phase in the first 10 seconds or shaking a little bit some connection cables of a breadboard - I got the two attached pictures. I read a post of an user w

Posted on February 28, 2017 at 12:56How to read a characteristic value which was written by android on Blue NRG.Please help

Posted on February 28, 2017 at 00:33Hey,   In my application there is a lot of high frequency vibration that I am not interested in. The goal is to detect acceleration along a single axis that lasts 200ms or longer, but is generally between 1/2 and 1/10 the magnitude of the noise (vibration readings). Finally, for performance reasons it is not feasible to read all the data from the accelerometer, an interrupt should only trigger when it is likely an event has occurred.    What I am trying currently: Stream to FIFO mode, adjusting threshold and duration in both 6D and AOI modes. 6D fails to trigger because vibrations send the reported acceleration bouncing back and forth between positive and negative values. AOI will trigger constantly because of the large magnitude of the vibrations. Is there anything else worth trying before looking for a different product? It seems like a product with a built in low

Posted on February 27, 2017 at 08:17Hello everyone,In the data sheet of LSM9DS1, it is stated in the first page that the device supports: Position and motion detection functionsClick/double-click recognitionHowever I cannot find anywhere in the data sheet describing how to use the features?  Could someone help me on this? Thanks a lot!#lsm9ds1-click-detection

Posted on February 24, 2017 at 20:11Hello everyone,To make this quick, I'm hoping to find any guidance on a particular issue we're having.We've developed a prototype wearable using ST's accel/gyro/magneto module. However we're trying to reduce the errors/drifts inherent to the Accel/Gyro (not concerned about the Magneto) and rather than using the common but complex Kalman filter, we're hoping to use the easier by rarer Explicit Complementary Filter algorithm to enhance the attitude of the system, preferably in C++ to use in our C# Application.Just not sure where to go or where to find answers.