MEMS (sensors)

Posted on April 30, 2018 at 12:25I am seeing some curious behaviour with the LSM303DLHC sensor. I am using the magnetometer only, reading at 200Hz. My software responds to interrupts on the DRDY pin by reading six bytes starting from register OUT_X_H_M. I also read the temperature - two bytes at TEMP_OUT_H_M - once a second.The configuration is as follows:    // Set CTRL_REG1_A to:    //    0000        : ODR[3:0] = 0000, Power down mode    //         0      : LPen = 0, normal mode    //          000   : Zen, Yen, Xen = 000, all axes disabled    //    0000_0000   : 0x00    register_write(A_I2C_ADDRESS, CTRL_REG1_A, 0x00);

Posted on April 27, 2018 at 09:15Please tell me the details on Interrupt and FIFO settings in ISM330DLC. I need to store the Gyroscope and Accelerometer data into the FIFO . Please tell me what changes i need to do in kernel source code of ism330dlc so that it will store the data into the FIFO.

Posted on April 16, 2018 at 12:37I am using LIS2DH12 on my custom designed board for a BLE application. I noticed that the PCB had a huge current draw than expected and on further digging found the accelerometer to be drawing the excessive current while in Power Down mode. Thorough testing revealed that the SA0 line used to select I2C address was the root cause of this problem. Connecting SA0 to ground (GND) led to huge current draw. However, connecting SA0 to VDD (logic HIGH) solved the huge current draw problem. Is this behaviour expected from the accelerometer? If yes, why? If not, what could be other possible factors leading to such behaviour. Thank you.#current-consumption #i2c-address

Posted on April 25, 2018 at 03:31Quote the datasheet:'Temperature data is stored inside TEMP_OUT_L (05h), TEMP_OUT_H (06h) as two’s complement data in 12-bit format, right-justified.'So if the sensor value is reading 0 and the temperature drops by 1/8th of a degree, I would expect the value to be 0xffff or 0x0fff - that is 0bxxxx111111111111. Since 111111111111 is 12 bit two's complement for -1, and the x bits are ignored.However this is not the case. The value I actually read is 0xefff / 0b1111111011111111 / -257. The value continues to count down by 1 per 1/8 degree from here.Can anyone explain what is going on here please?

Posted on April 23, 2018 at 21:33Hi, I downloaded the Unico 6.0.0.0 and selected the STEVAL-MKI179V1 for LIS2DW12 sensor. I am using the motherboard STEVAL-MKI109V3 and i getting the same error. How to solve firmware issue for this motherboard?I have attached the snapshot of my error here in this question. Looking for a quick response. Thank you#steval-mki109v3 #motherboard #steval-mki179v1 #firmwareupgrade

Posted on April 24, 2018 at 17:11I am trying to configure an interrupt on a LIS2DH12 in order to detect when the device is being hit.I tried just configuring one axes to generate the interrupt. But Interrupt is never being fired (Or it is fired constantly). This is my current configuration:20---- 67 21---- 0 22---- 40 23---- 0 24---- 8 25---- 0 26---- 0 27---- ff 28---- 40 29---- 0 2a---- c0 2b---- ff 2c---- 80 2d---- 44 2e---- 0 2f---- 20 30---- 10 31---- 55 32---- 40 33---- 0 34---- 0 35---- 0 36---- 0 37---- 0 38---- 0 39---- 0 3a---- 0 3b---- 0 3c---- 0 3d---- 0 3e---- 0Leaving the device over the table where I work, gives a constant measurement of:x:     0    y:    0    z

Posted on April 24, 2018 at 13:34Hello to allI'm trying to use MotionFX sensor fusion library in my application with STM32F4.It seems to me that the 9X mode works good enough. But I'm confused about my results during sensor rotation around 3 axis:1) Pitch varied in the range -90 - +90deg (Horizon 0deg, Straight up +90deg and then decreasing to 0deg with increasing the angle, Straight down -90deg and then inceasing to 0deg)2) Roll varied in the range -180 - +180deg (Horizon 0deg, +179 = Full roll right and –179 = Full roll left)3) Yaw varied in the range -180 - +180deg (North 0deg, East +90deg, South +180deg, West -90deg)Are the results (particularly the range of Pitch) good or not?Kind regards, Anton.

Posted on November 10, 2017 at 09:57when i use STMicro motherboard STEVAL-MKI109V3 to evaluate the MEMS sensor board STEVAL-MKI136V1 and STEVAL-MKI179V1, found some problems.1. I can not find the STEVAL-MKI179V1 in the device list of Unico.    How to add new STEVAL board for other modules into Unico device list?2. Use STEVAL-MKI109V3 to evaluate the STEVAL-MKI136V1, found error ''The device slected is not supported by the motherboard ''    How to fix the fireware version error?

Posted on April 24, 2018 at 10:31Hi..I use STEVAL-MKI109V2(Demo board) and MKI160V1(sensor).and i use IAR Embedded Workbench V7.20 Version..so when i open to project file,comming message like this..'Broken options were detected in the project file A backup copy will be made(see log window for detail)'and next message is...--> The project 'emotion' contails the unknow to 'CADI_ID'--> The project 'emotion' contails the unknow to 'TIFET_ID'is it need to upgrade to over IAR 7.70 Ver??thanks...mailto:xfile2580@daum.net#mki160v1 #mki109v2

Posted on April 24, 2018 at 10:20Hi..i use steval-mki1092V2(demo board) with mki160V1(sensor)..so i was download to en.stsw-mki109w.zip(for Windows) file...and  i use to IAR Embeded Work...7.20 Version...so when i open project file,come to msg like this.. 'Broken Options were detected in the project file A backup copy will be made'(See log window for detail)'and next msg is...--> The project 'emotion' contains the unknown to 'CADI_ID'--> The project 'emotion' contains the unknown to 'TIFET_ID'is it need upgrade to IAR 7.70 version ??thanks..mailto:xfile2580@daum.net

Posted on April 03, 2018 at 00:53Hi guys,I have STEVAL-MKI183V1 connected to stm32l476rg NUCLEO. I have downloaded the C example code. Setup the SPI and the Interrupt pin using STM32CubeMX. With the help of some example code i hooked it all up. I get correct value for WHO_AM_I (0Fh) register. This is what i get on the logical analyzer. First one is the temperature and the second one is the air pressure. I get 43.06 degC and air pressure of about 1027 hPa which puts me -120m underground. I am quite sure i am not underground and it is not 43 deg.  After reset I am using the default settings 10hz, BDU bit set. No change from the example.What i have noticed is that when i apply heat to the sensor the air pressure goes down, while the temperature is more or less the same. Any advice? What have i missed? Magic spell, as long as it does the trick?&n

Posted on April 13, 2018 at 15:28 Hello guys, The LIS3DSH is on the development board itself, which is STM32F407G (ver MB997D). And I am using CubeMX to generate the code. Here is the wiring Function LIS3DSH Master SDA PA7 PINB7 SCL PA5 PINB6 SEL/SDO PA6 3V Pin At first, I used these two API calls before I realised that HAL_I2C_Mem_Write and HAL_I2C_Mem_Read are the right ones. uint8_t slavAddr = 0x3A; //[7-bit adddress is 0001 111x] uint8_t ID,whoAmI=0x0F; int main(void){ HAL_Init(); SystemClock_Config(); MX_GPIO_Init(); MX_I2C1_Init(); HAL_I2C_Master_Transmit(&hi2c1,slavAddr,&whoAmI,1,100); HAL_I2C_Master_Receive(&hi2c1,slavAddr,&ID,1,100); while (1) { } }�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�?�

Posted on April 19, 2018 at 17:53Hey, I am working with the LIS3DH accelerometer and would like to know if there are any energy comparison values between spi and i2c modes of operation?Any related information would be of great help!Thanks!#lis3dh-spi #lis3dh

Posted on November 17, 2017 at 15:13Hi, I am trying to read the LIS2DH12 using the I2C and DMA.I got everything configured via STM32CubeMx. When I want to read the LIS2DH12 (WHO_AM_I @0x0F) I call:HAL_I2C_Master_Receive_DMA(&hi2c1, (uint16_t)SLAVE_ADDRESS, (uint8_t *)I2CRxBuf, 1);I have defined the below: SLAVE_ADDRESS 0x330F   // (slave address 0x33 and read adress 0x0Fchar I2CRxBuf[5];I wait for it to complete the receive first:while (HAL_I2C_GetState(&hi2c1) != HAL_I2C_STATE_READY);Then print the value on the screen. It always stay zero.What am I doing wrong?

Posted on April 18, 2018 at 15:42Hello,Currently,  am working with  lis2dh12 mem sensor for my ble application. I am using accelerometer to detect movement and then reading data from accelerometer using bypass mode. During no movement, the power consumption reading of my device is 20 uA  with advertisement interval 4 sec while during movement it is 500 uA with advertisement interval 100 msec. I also did some measurement without accelerometer. So my current consumption for advertisement interval 4 sec is around 14 uA while at 100 msec it is around 180 uA.I need to optimize my current consumption so I would like to enable fifo after movement is detected and hence reduce the usage of SPI.My questions regarding this effort are1) Can I have FIFO WTM interrupt on pin 2 and movement threshold on pin 1? If there is any online example of such scenario, kindly refer it to me.2)  500 uA  i

Posted on February 28, 2018 at 05:30If i shake the sensor board, acceleration is produced in the corresponding axis. but if i tap on the board, to produce higher g values, say 200g - 400g, the acceleration spike is seen in all the 3 axis, not just axis which I had tapped.#h3lis331dl #h3lis331dl-working

Posted on April 19, 2018 at 02:10I am using a STEVAL-MKI109v2 with a STEVAL-MKI172v1 sensor board. When I run Unico 6.0.0.0 the MKI109v2 is not in the list of devices but the MKI172v1 is. When I select MKI172v1 and attempt to connect I get the following error:ERROR: The adapter board has not been Recognized. The WHO_AM_I register does not match the device selected.Any idea what could be wrong?#unico-mki109-mki172-who_am_i

Posted on April 03, 2018 at 08:59I have a SensorTile Kit (STLKT01V1) running the http://www.st.com/content/st_com/en/products/embedded-software/mcus-embedded-software/stm32-embedded-software/stm32-ode-function-pack-sw/fp-sns-allmems1.htmlwhich I can control via a phone running the Blue MS app.But that app only records one kind of data at a time. So I can either record audio OR i can log sensor data like accelerometer etc. I want to record both of these simultaneously.How do I go about doing that?I also tried looking at other available demos, especially AudioLoop (for mic) and DataLog (for sensors) but I couldn't get them working simultaneously.

Posted on November 06, 2017 at 17:26The original post was too long to process during our migration. Please click on the attachment to read the original post.

Posted on April 17, 2018 at 23:55Hi All,I'm using an LIS2DE12 in stream mode with the watermark set to 15 FIFO entries and with the WTM bit being driven out INT1. When INT1/WTM goes high, I read out 16 FIFO entries and, as expected, INT1/WTM goes low about halfway through the transfer when the number of remaining FIFO entries falls below the watermark. However, occasionally, INT1/WTM goes low much later in the transfer or may not go low at all while reading the FIFO.In my configuration, the SPI clock runs at 100 KHz and the LIS2DE12 sample rate is 1.62 KHz which means I'm able to pull out FIFO entries a bit faster than 1*ODR so I always expect INT1/WTM to go low sometime during the transfer.In the attached trace, the INT1/WTM signal is at the top. When it goes high, CS goes low to start the transfer. In most cases, INT1/WTM goes low half way through the transfer but in the highlighted transfer, it does not. Since the timing

Posted on April 11, 2018 at 17:33What is LSM9DS1 standby consumption (all sensors off)?The datasheet says nothing, no value in Electrical characteristics section.Its predecessor LSM9DS0 has 6uA typical.

Posted on April 17, 2018 at 10:44From the datasheet ''..This imbalance is measured using charge integration in response to a voltage pulse applied to the capacitor.'' I would want to know at what rate this measurement is done. The maximum data rate of output to the user is 1 kHz. Which means ADC measurements performed must be at an higher rate inside the IC. Is it possible to know the sampling frequency of this internal ADC and also the type of ADC used? Is the type of ADC used integration ADC since 'charge integration' is mentioned? More detailed explanation is required in these aspects. Please help..

Posted on February 01, 2018 at 16:17Hello All,We are doing a wearable product where we using LSM6DS3 & M24C64 but power consumption much high than specified.LSM6DS3 is taking around 300uA just by powering on. As we understand from datasheet by default LSM6DS3 is in power off mode. which should have power consumption of 6uA.We also can't read accel value without sending power on command which prove that it's power off mode but power consumption is 300uA.Same situation we are facing with M24C64 memory. As we understand from datasheet if no i2c communication it automaticly go into sleep mode and having power consumption of 2uA. But even on no communication M24C64 power consumption is approx 280uAAny suggestion would be appreciated.

Posted on February 26, 2018 at 12:02Hello allMy goal is to use two INT pins to generate two interrupts in a device which will be used in a car. INT2 will be pulled when a crash of the car is detected and INT1 when the car moves.Here is my init setting:CTRL_REG1 = 0x27 //10Hz, normal power mode, ZXY enableCTRL_REG2 = 0x01 // HP filter for INT1CTRL_REG3 = 0x40 //IA1 enableCTRL_REG4 = 0x90 //4g | BDUCTRL_REG5 = 0x0A //latch on INT1 and INT2CTRL_REG6 = 0x22 //active low & INT2 enableINT2_THS     = 0x6D //~3500mgINT2_DURATION = 0x00 // 0.1*0s INT2_CFG     = 0x2A  //OR, X,Y,Z higher than thresholdINT1_THS     = 0x02 //INT1_DURATION = 0x03 //

Posted on April 13, 2018 at 14:16Hello,I am trying to compare LIS3DH and LSM9DS1 (accelerometer part) and I am suprised by the result:The LIS3DH has the configuration: CTRL1: 0x67 (ODR = 200Hz, LPen=0, ) CTRL4: 0xA8 (BDU, 8g, HR)   => sampling frequency = 200Hz and BW=ODR/9=22HzThe LSM9DS1 has the configuration: CTRL5:0x38 (no decimation), CTRL6: 0x98 (ODR = 238Hz, 8g, bandwidth determined by ODR, ) CTRL7: 0x80 (HR, filsters bypassed) CTRL8: 0x44 (BDU, IF_ADD_INC)   => sampling frequency = 238Hz and BW=105HzBut when I capture data with both PCBAs tightly attached, the LIS3DH signals have more amplitude and seems to have a higher bandwith.Did I missed something or is there a problem?Do you suggest another configuration for the LSM9DS1?