MEMS and sensors

Posted on August 01, 2017 at 20:37Hello,I am attempting to integrate the https://community.st.com/tags♯/?tags=lsm303agr into an existing product and I am having difficulties bringing down the power consumption of the LSM303AGR to reasonable levels. As I understand it, the module should be consuming only around 3uA or so when idling, but I am seeing more like 300uA, which seems to be inline with power consumption while the magnetometer is taking measurements.The steps I am taking to put the device into sleep mode are clearing the ODR[3:0] on CTRL_REG1_A which the datasheet indicates should put the accelerometer in power down mode and setting bits MD[1:0] in CFG_REG_A_M. After writing to these registers I read them back to confirm that the changes occur. For reference I am communicating with the module over I2C.Are there any known bugs with sleep mode or possible gotchas that could be responsible with the issues I am seeing?Thanks,Jason#sleep-mode #lsm303agr #lowpower-sleep #s

Posted on August 14, 2017 at 17:33Hi,I'm using LSM6DSL and unable to operate X axis on accelerometer. The Y and Z axes give me the right results but X axis is stable at 32756 and changes only by 5 points. I have 4 devices with LSM6DSL and all behave same. Tested even without FIFO (same result). Because 4 devices do the same, I'm not sure of device fault.Here is my setup:/* Enable register address automatically incremented during a multiple byte access with a serial interface. */LSM6DSL_ACC_GYRO_W_IF_Addr_Incr(NULL, LSM6DSL_ACC_GYRO_IF_INC_ENABLED); /* Enable BDU */LSM6DSL_ACC_GYRO_W_BDU(NULL, LSM6DSL_ACC_GYRO_BDU_BLOCK_UPDATE );// Low power enabled (XL_HM_MODE = 1)LSM6DSL_ACC_GYRO_W_LowPower_XL(NULL, LSM6DSL_ACC_GYRO_LP_XL_DISABLED) ;/* Scale selection. */LSM6DSL_ACC_GYRO_W_FS_XL(NULL, LSM6DSL_ACC_GYRO_FS_XL_4g );/* Set accelero FIFO decimation */LSM6DSL_ACC_GYRO_W_DEC_FIFO_XL(NULL, LSM6DSL_ACC_GYRO_DEC_FIFO_XL_NO_DECIMATION); /* Set FIFO ODR to highest value */LSM6DSL_ACC_GYRO

Posted on February 15, 2017 at 10:12We're trying to get some LIS3MDL parts for some sample boards we are making. Seems there is no supply anywhere. Does anyone know what the problem is, or when it's likely to be sorted? Better still: any ideas where I can get say 5 of these sensors ASAP?#lis3mdl

Posted on May 01, 2017 at 18:41We are making roll measurements (atan2(ay,az)) using the LSM9DS1's accelerometer.   We see extremely little error, just fractions of a degree.  Since this is within our required accuracy, we are thinking that we don't need to do any calibration to get our roll measurement.  Is this true?  We are confused by the datasheet which seems to suggest that errors as high as 90 mg are possible.  If a 90 mg error occurred in the Y axis, this alone would generate a 5 degree error in our roll measurement, yet we are seeing almost no error.  Is this calibrated in the factory?  Should we do our own calibration to ensure that we have errors less than 1 degree?  Thanks!

Posted on September 29, 2016 at 13:03How the 25 degree field of view of VL53LOX TOF sensor was covered? If there any algorithm to measure the distance with in that field of view ?

Posted on July 23, 2017 at 16:03I am working with the VL6180x and I would like to connect multiple sensors via an expansion board by ST (*). Therefore I want to communicate to single sensors, so I have to change each single I2C-Device-Address via the 0x212 register. My method is contacting the first sensor via the standard value 0x29 and changing its address. Then I connect the second sensor who still has the 0x29 address and thus I change this one's address, too, and so on.... The problem is: As soon as the whole device is unplugged from my PC, the addresses become reset and hence I'd have to do the whole procedure with plugging in each sensor one by one again. Is there a better method for contacting single sensors?I am not working with the API by ST, but I am just contacting the I2C registers listed in the data sheet.(*) The board used is the X-NUCLEO-6180XA1#sensor #multiple #vl6180x

Posted on August 16, 2017 at 11:52The accelerometer on my STEVAL-WESU1 has stopped reporting data. For instance, in the Plot data demo, I can see:Data: X: 0  Y: 0  Z: 0After I charge it, it does report some data but only for some seconds.I can see that the Magnetometer, Temperature or Pressure sensors are functioning normally and reporting data.

Posted on August 16, 2017 at 11:44My STEVAL-WESU1 does not report any Accelerometer/Gyrometer data anymore.In the Plot data menu, I can see:Data: (X: 0 Y: 0 Z: 0)If I charge my STEVAL and start the demo, it will report data for some seconds, and then suddendly stops functioning.But I can see that Magnetometer, Pressure and Temperature are reporting data and functionning normally.

Posted on August 15, 2017 at 23:13Hi,I'm trying to use LIS2DE12 for position recognition of device, but i faced some strange problems !1- I didn't find any solution to correct the offset values of X Y Z dimensions ! i.e after soldering the chip, when my device is on a flat surface which X and Y shod be 0 and Z = g, there is some offset (because of mechanical placement of chip or board in device). i.e X = 4, Y = -3 . now i want to adjust X dimension to interrupt after + - 15 degrees movement, but the problem i face is, i can only set one value for both plus and minus values ! means i can't set -4 Threshold and +14 THS !I only can set i.e 10 in THS register, so X will interrupt on +10 or -10. because of the mechanical offset error, device will interrupt after 6 (4 to 10) steps on positive side but -14 (4 to -10) steps on negative side !how can i solve this issue ?i like to be able to set different values for upper or lower values ...another problem is i didn't see any way to set di

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! #accelerometer-noise

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 were right. If I use the 0.0008s timesteps (1/1250Hz) for the logged 5000Hz-mode bef

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.#mp45dt02-m #steval-mki129v1

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 and HAL_I2S_RxCpltCallback are occuring, bu

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, 0000 [0][0][FF_IA][SLP_STAT]--[WU_IA][X_WU][Y_WU][Z_WU]6d src: 0010, 0000 [0][6d_IA][ZH][ZL]--[YH][YL][XH][XL]wkupths: 10, 4 [SINGLE_DO

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 pressure data is ready    pres_raw  = i2c_smbus_read_byte_data(file_i2c, LPS25HB_PRESS_OUT_XL);  &nbsp

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 ?