MEMS (sensors)

Posted on February 03, 2017 at 16:40Hi all,I'm using a LIS3DH accelerometer and I would like to detect the device orientation in the space. According to the specifications I could do this by means of the 6D orientation detection function, but I'm not getting any result. Can anyone tell me which is the correct setting of the registers of the LIS3DH in order to use the 6D orientation detection function?Thanks to everybody who can help.#lis3dh

Posted on October 29, 2016 at 12:25Hi, I can read from LPS25HB ST description page that it have ''High-resolution mode: 0.01 hPa RMS'' while on LPS22HB there's nothing about this. But looking at either datasheed I've found that: LPS22HB PAccT +/-0.1hPa Pnoise 0.0075hPa LPS25HB PAccT +/-0.2hPa Pnoise 0.01hPa So, despite LPS22HB doesn't have this description add, it's still more precise than LPS25HB. It's correct or I'm missing something?

Posted on June 30, 2017 at 22:32Hi,changing the timing budget affects the measurment accurancy/speed/range.  This is done with the function VL53L0_SetMeasurementTimingBudgetMicroSeconds(..). Does this function affects the measurements parameter in the same way in case of CONTINUOUS_TIMED mode? So that I can take care about the timing budget (profile: long range, high acc.) and the internal time periode using the function VL53L0X_SetInterMeasurementPeriodMilliSeconds(...)?Such like:Timing Budget: 33 msTime Periode: 100 msWith best regardsAlex

Posted on August 16, 2016 at 17:37Hi, I've a design based on LIS344ALH where the noise level is a very sensitive parameter since I need to measure signals in the mg range. I would like to move to a full digital component and I'm looking to the LIS2HH12. Unfortunetely, the datasheet doesn't contain any information about noise. Can I get this information? Another question: almost all accelerometer's datasheets talk about the mechanical noise only in �g/sqrt(Hz), but without giving a full noise figure taking into account the acquisition chain. For analog accelerometers, could I consider that I can map the value for mechanical noise to an electrical noise value using the sensitivity? For digital accelerometers, could Iconsider that I can map the value for mechanical noise to an digital noise (in LSB) value using the sensitivity? Thanks! #acceleromete

Posted on July 17, 2015 at 15:05Hello,I am planning to operate the LIS3DH accelerometer in low power mode (resulting in an output data rate of 5kHz according to Table 26 in the datasheet).In Table 3 in the datasheet a sensitivity of 12mg/digit is given, but I think this is referring to the high resolution mode (similar to the specification given for the LIS2DH12 accelerometer). Which sensitivity will I achieve in the low power mode with the LIS3DH (measurement range set to +-16g)? Thanks! #mems-accelerometer

Posted on May 09, 2016 at 15:33Hello all, I want to use the LIS3DH accelerometer and a Steval-MK1109v2 Motherboard with the ST Unico GUI for logging Acceleration data. The datasheet of the LIS3DH shows the possibility to meassure a bandwidth up to 5000Hz, which i need for my shaker meassurements. I used the Unico GUI to configure the Sensor at +-2g and the 5000Hz mode. I tried a 160Hz sine signal at the shaker and made an online FFT at the Unico GUI, but there was shown a peak at about ~600Hz, so i took a look at the logged data in the .txt-file. I wanted to add a timepath but recognised that the number of the lines weren�t right at all. I logged data at about 3 seconds but got only roundabout 4000 lines. With a ODR of 5000Hz i expected up to 16000 lines. I tested the modes with 400Hz and 1250Hz and both online-FFT an logged data wer

Posted on August 11, 2017 at 19:00Hello,  I am trying to use the http://www.st.com/en/evaluation-tools/steval-mki129v1.html board on a breadboard.  It has a http://www.st.com/en/audio-ics/mp45dt02-m.html.  I am trying to resolve the two data sheets to determine the mapping to the coupon pins.  Can anybody tell me the pin mappings for the coupon board with pins ordered from the top as in the attached photo?  I also attached the relevant diagram from the two data sheets.Thanks in advance for any help you can provide.

Posted on August 10, 2017 at 13:33Hi community!So far i have been developing my audio application on discovery board STM32F407 (there is a embedded MEMS microphone connected to I2S2), I have been able to configure I2S2 periphery and acquire data with relative ease. But now i had to move to custom hardware (i went for STM32F427VG). In discovery board's schematic i have found that the microphone used is MP45DT02. So i have used the very same in my custom board. My finished board come so i have tryed to apply the same settings for I2S and expected, that i will have the same results. After compile the program and loadto the target it didnt work properly, so i started troubleshooting by looking at I2S circullar buffer.  The buffer is uint16_t type and after inspecting its content after start it was properly initialized to 0, when i start the program and stop i can see that my HAL_I2S_RxHalfCpltCallback

Posted on August 06, 2017 at 20:02I have an IDB05A1 using aci_gatt_update_char_value. This call works for anything using 4 byte array sizes or smaller, but it returns BLE_STATUS_ERROR for arrays larger than this. I'm calling both aci_gatt_init and aci_gap_init_IDB05A1 during initialization. Any ideas?https://community.st.com/s/global-search/x-nucleo-idb05a1

Posted on February 15, 2017 at 06:13I am looking for some code examples or technical notes on programming the state machine in LSM330TR but couldn't find any in ST.com. Has anyone found these ? Could you please share if you have.#lsm330-state-machine

Posted on June 05, 2014 at 16:02Hi, I bought the iNemo-M1 Board.I connect it to PC by USB board, but PC not recognized the board.The board is aready programmed?I need to select an iNemo DFu firmware to program?Thanks.Eduardo Scherrer #inemo-m1-board.

Posted on August 01, 2017 at 21:23I'm trying to configure my LIS2DS12 accelerometer such that I can receive both wake and tap events. Whenever I enable (set the INT1_WU pin in ctrl4) I don't get tap events. I have three cases:1. enable just the wake up interrupt: wake up interrupts occur2. enable just the double tap event: tap interrupts occur3. enable both the double tap and wake up interrupts: only wake up events occur.Is there a way to be able to see both interrupts?Register values when I try to configure both interrupts:status: 0000, 1001 [FIFO_THS][WU_IA][SLP_STATE][DTAP]--[STAP][6D_IA][FF_IA][DRDY]statdu: 0000, 1001 [OVR][WU_IA][SLP_STATE][DTAP]--[STAP][6D_IA][FF_IA][DRDY]func_ck: 0000, 0000 [TILT_INT][FS_SRC][SIG_MOT]--[RST_SIG_MOT][RST_PED][STP_DET][GATE_FUNC]tapsrc : 0010, 0100 [0][TAP_IA][STAP][DTAP]--[TAPSGN][XTAP][YTAP][ZTAP]wkupsrc: 0000,

Posted on August 01, 2017 at 18:56Hi all,I am evaluating the LPS25HB pressure sensor on iMX6 host processor, I am interested in getting the altitude for our usecase.The problem is  I am getting consistent value of pressure with no change even when I  moved from floor to floor in the elevator. Can someone help me in solving this issue?Here is the simple code which I am using:const double read_pressure(void){    double pressure = 0.0;    int pres_raw = 0;    unsigned char pdataReady = 0;   qDebug() << Q_FUNC_INFO << 'entry';    pdataReady = i2c_smbus_read_byte_data(file_i2c, LPS25HB_STATUS_REG);    while(!(pdataReady & 0x02))        pdataReady = i2c_smbus_read_byte_data(file_i2c, LPS25HB_STATUS_REG); //loop until pressu

Posted on July 27, 2017 at 18:53Hi to all, I was taking a look to LIS344ALH accelerometer for a project where I need to place MEMS accelerometer into Raspberry board.I've heard there is a way to reduce acceleration noise placing sensors in array (e.g. using 4 LIS344ALH instead single one).Is this correct? How does it work?Thanks.

Posted on June 21, 2017 at 22:20I am using the BlueNRG-MS on SensorTile and loaded the BlueMicrosystem2 firmware.When connecting/disconnecting with ST BlueMS App using iPhone.  Everything is OK.When testing the same with Android phone (Android 5.0.1), it can connect and communicate.However, after exit the ST BlueMS App and try to Scan for device again.  The device cannot be found anymore.Checking the firmware, the status indicate device still in 'connected' state.Should there be a timeout for this ?The only way to have device advertise again is 'reset' firmwareThanks for advice.

Posted on July 26, 2017 at 23:26HW : STM32L476RG-SensorTileSW : SW4STM32Tried to enable the debug print through USB.I was using the BlueMicrosystem2_V2.2.0.  Enable  #define OSX_BMS_ENABLE_PRINTF and rebuild code will work.Can see all the print out.Recently got the new STM32CubeFunctionPack_MOTENV1_V3.0.0.Followed the instruction in main.c to rebuild with #define  MOTENV1_ENABLE_PRINTF But the ST Virtual COM port not even showing up in PC device managerIs there additional work need to be done ?

Posted on July 25, 2017 at 20:35LIS3MDL doc says take 16 bit signed Temperature Register values, divide by 8, and add 25 degrees C.   I get a value that is always about 11.5 degrees  warmer than what the ASM330LXH on the same board is reporting, and the ASM330LXH appears to be pretty close to actual room temperature.    Is it really a 25 degree offset? or should it be 12.5 degree offset?  value 0x0057 = 87;  87/8 = 10.875;  10.875 + 25 = 35.875 degrees C = 96.575 degrees F.  It just isn't that hot in here, and the two sensors are physically very close to each other.Is this temperature measurement only useful for relative temperatures?

Posted on July 23, 2017 at 16:54Hi all ,    I used BlueNRG-MS found a problem , the MCU is freescale chip and used SPI communcation with BlueNRG-MS , but the MCU send the configuration information to BlueNRG-MS , start I could read 0x04 0xFF 0x03 0x01 0x00 0x01, and then write configuration information , but each only read 0x04 0x10 0x01 0x00 . is not the correct data .This image is first read the data , and comparison of normal board data is correct .This is every send configuration information , and read data , is always this data , but normal is not is data .

Posted on June 13, 2017 at 14:08I am working with IIS2DH accelorometer an I would like to configure single/double click tap detection. For that, I have done following configuration:I2C_WriteByte(&ctrl_1,1,0x5F);  I2C_WriteByte(&ctrl_3,1,0x80); I2C_WriteByte(&ctrl_6,1,0x82); I2C_WriteByte(&ctrl_4,1,0x00); I2C_WriteByte(&int1_config,1,0x00);  I2C_WriteByte(&ctrl_5,1,0x40); I2C_WriteByte(&click_config,1,0x15);I read click source register for single click detection but values are different every time. Also,interrupt flag not set for microcontoller.Is there any thing need to be wrong in my configuration?Is any application note for IIS2DH(DM00171283)?

Posted on July 17, 2017 at 08:22hello, I have gone through the datasheet and app note of LIS3MDL. But i am not able to get how block data update bit work i.e. if someone has set the BDU bit and if I read registers through I2C one by one, then how the ic internally gets idea that all the registers have been read and got the data of same sample?Also can anyone please elaborate about ODR and its working in LIS3MDL

Posted on July 19, 2017 at 14:30I have done following configuration to detect double click. I am able to detect double tap but it is consider four times.I2C_WriteByte(&ctrl_1,1,0x5F); I2C_WriteByte(&ctrl_3,1,0x80); I2C_WriteByte(&ctrl_6,1,0x82); I2C_WriteByte(&ctrl_4,1,0x20); I2C_WriteByte(&int1_config,1,0x00); I2C_WriteByte(&ctrl_5,1,0x40); I2C_WriteByte(&click_config,1,0x2A); I2C_WriteByte(&time_limit,1,0x05); I2C_WriteByte(&click_ths,1,0x30); I2C_WriteByte(&time_latency,1,0x05); I2C_WriteByte(&TIME_WINDOW,1,0x80);while(1) { click = I2C_ReadByte(&click_src,1);    if((click & (1<<6)))    {       print('click detection');   }}Is anything wrong with my configuration? How I can overcome t

Posted on July 18, 2017 at 10:45Hi, I am working with LIS2DE12 accelerometer, I want detect any new data is updated  to temperature and x,y,z axis registers.can any one provide steps for configuration. 

Posted on July 17, 2017 at 16:25Hello,I try to read acceleration values from a LIS3DSHTR using the STM32F091 �C. I use SPI with DMA to read the values but I have trouble with the incoming datas in the RxBuffer.On my two screenshots you can see the bus communication and the position of the data inside my RxBuffer. The order is totally wrong.I hope someone can check the source code. I hope you can find a stupid mistake void SPI_init(){    SPI_InitTypeDef SPI_InitStructure;    // clk    RCC->AHBENR |= RCC_AHBENR_GPIOAEN;    RCC->APB2ENR |= RCC_APB2ENR_SPI1EN;    // set af mode    GPIOA->MODER = ( GPIOA->MODER & ~(GPIO_MODER_MODER5 | GPIO_MODER_MODER6 | GPIO_MODER_MODER7));    GPIOA->MODER |= ( GPIO_MODER_MODER5_1 | GPIO_MODER_MODER6_1 | GPIO_MODER_M

Posted on March 29, 2017 at 12:47Hello STM!I am facing a new goal: I want to build my own diferencial beamforming 2 MEMS PDM microphone array to achieve kardioid directivity pattern.So i need to get data out of two MEMS mics simultaneously ... i mean literally get samples at the same time (because the beamforming depend havily on time that sound travel through space, so i will try not to add any delay between the two mics samples). So i am thinking what approach for data aquisition here is the best.I got two variants at the top of my head. I will mention i am going to use probably some of STM32F4 168 MHz or higher (reason is that i developed so far a lot of my app using single microphone at this mcu and it had suitable performance for all the signal processing needed)    1. Variant:Aquire both PDM via one I2S data line using the 'trick' with double PDM clk frequency fro

Posted on July 14, 2017 at 07:24The magnetometer on my device has different scale and offset on its axes.This is because of influence of hard iron on the board. So, it needs to be calibrated. I've read https://my.st.com/resource/en/design_tip/dm00286302.pdf and hadn't understood about rotated ellipsoid. Rotated about what? I made calculations according this manual with matlab. Offsets and gains are adequate, but rotation matrix is strange. When I fit the data with offsets and gains, the angles (yaw, pitch, roll) I computed are normal. When I fit with offsets, rotation matrix and gains, the angles are strange. The second question. When I fit the data with normal calibration values all vectors have magnitude 1. How to convert it back to gauss?The crosses are the original data, the rounds are tra