MEMS (sensors)

Posted on June 07, 2018 at 13:20Hi,I am using a LSM303D with a Adafruit Feather M0 and want to detect spikes in the magnetic fields, preferably for all the axes, and want to use interrupts.I have the interrupts working when any of the axes goes above (or below) the given threshold value. The problem is that I need to detect spikes in either direction from the normal value (usually far from zero) of all the axes but the threshold only works around (based on) zero. Currently, I use the offset parameters to make the values given by the magnetometer be around zero by default. Now I would like to set the threshold to lets say +-200 (as shown in the attached image) but from my testing it seems that the threshold does not take the offset into account and actually tests against the measured magnetic values.Is there a way to set the offset so that all values are around zero and also use a threshold value that uses the offset so that I

Posted on June 04, 2018 at 14:21HiIs there any comparison table?Best regards.Jokin

Posted on April 10, 2018 at 14:21Hi,I'm trying the example software for the BlueCoin, also DataLog. The USB streaming of data is working the way it's written in a Start guide. But I'm not moving forward with DataLog on SD Card. I'm going through the following steps:1. Setting LoggingInterface = SDCARD_Datalog in main.c2. loading program onto BlueCoin3. Connecting BlueCoin to Cradle, which is connected to battery and has SD in it.4. Tapping on a board, the way it's written in a guide.Result: nothing happens. When I open the SD Card folder, there's nothing to see.I also tried different SD card, didn't help.Does anyone have the same issue and could help me?Thanks#sdcard-logging #bluecoin #datalog

Posted on June 05, 2018 at 14:15Hi How to interface or bridge up X-NUCLEO-IKS01A1  to Nucleo144 board. I ask this question because the Pin out placing for both the boards doesnt fit as it fits for Nucleo64/32. ThanksPhani.#l4r5zi #x-nucleo-iks01a1 #nucleo144 #nucleo-l4r5zi

Posted on June 05, 2018 at 09:38Hello ,     I am working on lis2mdl sensor getting raw data values like below.C5 FF B9 FF 12 00 C5 FFthese values are accurate or not .if values getting correct may i know how to do calibration for that. my pseudo code.//who_iam HAL_I2C_Mem_Read(&hi2c1, 0x3D, 0x4F, I2C_MEMADD_SIZE_8BIT, buff, 1, 1000); //status HAL_I2C_Mem_Read(&hi2c1, 0x3D, 0x67, I2C_MEMADD_SIZE_8BIT, buff1, 1, 1000);//raw data HAL_I2C_Mem_Read(&hi2c1, 0x3D, 0xE8, I2C_MEMADD_SIZE_8BIT, Rawdata, 8, 1000);please kindly help me.Thanks & Regards,krish.

Posted on June 04, 2018 at 23:53Good day everyone!I am trying to use a FIFO watermark interrupt on LSM6DS33 accelerometer. For some reason, the interrupt doesn't happen. Other interrupts (Free-fall, movement, significant motion) work just fine, so it's not a hardware issue. Here is how I set up my LSM6DS33:/* Turn on the accelerometer ODR_XL = 26 Hz, FS_XL = 2g */CTRL1_XL = 0x24; /* Latch interrupt */TAP_CFG = 0x01; /* set FIFO threshold level */FIFO_CTRL1 = LSM6DS_THRESHOLD & 0x00FF;FIFO_CTRL2 = (LSM6DS_THRESHOLD & 0x0F00) >> 8; /* enable FIFO depth limitation */CTRL4_C = 0x01; /* reset FIFO */FIFO_CTRL5 = 0x00; /* enable accelerometer and gyro readings */FIFO_CTRL3 = 0x09;/* set FIFO mode, ODR 26Hz */FIFO_CTRL5 = 0x11; /* FIFO watermark reach interrupt driven to INT2 pin */INT2_CTRL = 0x08;I trie

Posted on June 04, 2018 at 15:13Hai, I want to build a data logger attached to an object travel at 3m/s. The requirement is the data logger must capture 74 sensor input (10 bit ADC) at every 3mm along the travel path. Thus in 1 second, the data logger must capture and save 3000 data per sensor and equivalent to 222 000 data for the whole 74 sensors.I never exposed to this task before thus could you give an idea of the architecture of such system?.#store-data #high-speed

Posted on June 02, 2018 at 10:08Hi ThereI recently got the STEVAL-STLKT01V1 sensor tile evaluation kit. I know that some of the sensors on the sensor tile are able to record linear acceleration (LSM303AGR). I have been looking at the provided examples and I can't see any linear acceleration sensor readings for any of the Sensor Tile applications. I did notice that the FP-SNS-ALLMEMS1 has a DataLogFusion example that is capable of logging linear acceleration but that appears to be through the MotionFX library for the Nucleo devices.Is there anyway of accessing the linear acceleration values from the sensor tile (through MotionFX or other means)?Thanks,Sheldon#linear #mems #acceleration #sensor-tile #motionfx

Posted on June 13, 2016 at 07:51Hi, I'm using the HTS221 with STM8L052C6. The communication channel is I2C. I am able to get the humidity data upto 99% RH. but above this after some point of reading the data,the sensor gets hanged and is not recoverable even after circuit is reset. i also found SDA line remains low in this condition. Any help would be greatly appreciated! thanks, unnati

Posted on May 31, 2018 at 13:46Hi,I am trying to use STM32 cube and ADXL345 ACC using SPI , this is my first time trying , and currently without luck as i am not able to read the accelerometer This is my SPI init code :void MX_SPI1_Init(void){hspi1.Instance = SPI1; hspi1.Init.Mode = SPI_MODE_MASTER; hspi1.Init.Direction = SPI_DIRECTION_2LINES; hspi1.Init.DataSize = SPI_DATASIZE_8BIT; hspi1.Init.CLKPolarity = SPI_POLARITY_LOW; hspi1.Init.CLKPhase = SPI_PHASE_1EDGE; hspi1.Init.NSS = SPI_NSS_SOFT; hspi1.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_16; hspi1.Init.FirstBit = SPI_FIRSTBIT_MSB; hspi1.Init.TIMode = SPI_TIMODE_DISABLE; hspi1.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE; hspi1.Init.CRCPolynomial = 10; if (HAL_SPI_Ini

Posted on April 06, 2018 at 01:33SensorTile: Auto Log on power-upAll:I have been tinkering with the SensorTile to use as-is for some data logging applications.  It wasn't my original intent, but it turned out to be so handy as-is I didn't see a need to make something ground-up for my very limited application.For this application the double-tap to start/stop didn't make sense, I wanted the device to start logging upon turning on and then log until I switched the device off.  To make this work reliably, I made the following changes: - Always create a new sequence number in the log file - Start logging on power-up - Flush the file system caches on every write so at most one data sample is lost on power down.See the post titled 'SensorTile SD Card Data Logger filename improvement' for the changes on ensuring each time a log file is created, it is a new sequence number.&nb

Posted on May 14, 2018 at 15:01Hi There, I am using the STM Accelerometer(LIS2DE12) with STM(stm32l432kb) controller. While getting the readings from the Accelerometer it gives the random value continuously. Even it shows false value at steady position.Here some how I am facing problem and need some idea and suggestion to solve this issue. If some one has the document , relevant data and sample code for it please let me know and help me.Thanks

Posted on May 27, 2018 at 18:12Hi, I'm using an LIS3DSH in a case where I want to periodically (say once every 50 milliseconds) get the most recent X,Y,Z position of the accelerometer and perform a calculation.My current approach is to just set a timer on my MCU to interrupt every 50 milliseconds.  During this interrupt routine I simply query the OUT_X, OUT_Y and OUT_Z registers of the LIS3DSH and then immediately perform my calculations.I've configured the block data update value (in register CTRL_REG4) on the LIS3DSH to 'continuous' and I'm not using the FIFO feature either (FIFO_CTRL = 'Bypass mode: FIFO turned off').  Additionally, I've configured the output data rate (in register CTRL_REG4) to 100 Hz.  Am I correct to believe this will result in the OUT_X, OUT_Y and OUT_Z register values continually being updated with the very latest accelerometer position data every 10 millisecon

Posted on May 28, 2018 at 18:14I am designing a robot using LSM6DSL.   I have it mounted in my system and trying to program.    Regarding the device's offset from the center of my machine.  Is there a simple register we can program with a simple physical location offset for the IMU from the center-of-pass of the product?  From I understand from the application notes, we will need to perform matrix operations to translate the accelerometer output to be as if the IMU was at the center-of-mass in their robot ?   Is this correct or is there an offset register that we can program?

Posted on May 28, 2018 at 16:17Please find the register settings as below NameAddressValueCTRL_REG30x230XE8CTRL_REG4,0x200X67CTRL_REG50x240XC0CTRL_REG60x250X10FIFO_CTRL0x2E0X0

Posted on May 28, 2018 at 09:24Hi everyone, I am using lis2dw12 accelerometer in my design.When i use STEVAL-MK179V1 with my custom board, the power consumption of LIS2DW12 seems normal.However, if i use LIS2DW12 IC soldered to my custom board, the power consumption increase to much.ow caI took the power consumption measurements while ACC is in power down mode. I configured the CS pin as output high and INT1 pin as input pull down. INT2 pin is not connected to anything.How can i solve my problem?Have a nice day

Posted on May 23, 2018 at 14:05We use VL53L1 connected to our MCU board without xVL53L1 expansion board as DevId = 0/1/2...By using MCU controlling the IO to off/on the XSHUT pin of sensor but during init. process,it fails at VL53L1_WaitDeviceBooted() with error message, VL53L1_ERROR_CONTROL_INTERFACEflow is as below:1. XSHUT with all 3 sensor to low for device-disable.2. each enable by XSHUT to high with standard init process as example code suggests-> it fails at this stage, (I2C seems not working..,,. is it related with ==/* 2V8 power mode selection codex 447463 */#ifdef USE_I2C_2V8Status = VL53L1_RdByte(Dev, VL53L1_PAD_I2C_HV__EXTSUP_CONFIG, &i); if (Status == VL53L1_ERROR_NONE) { i = (i & 0xfe) | 0x01; Status = VL53L1_WrByte(Dev, VL53L1_PAD_I2C_HV__EXTSUP_CONFIG,

Posted on May 24, 2018 at 18:36I'm trying to use the LIS3DSH accelerometer with a TI TM4C1294 development board and running into some issues.  I'm using I2C communication between the accelrometer and TM4C.  I have a fairly simple code example attached, which queries multiple registers and reports them to a terminal using UART program (screenshot below).As can be seen in the terminal program, the values read by the software frequently differ from iteration to iteration.  I expect to be getting 0x3F for ''who am I'', 0x21 for ''info1'' and probably 0x0F for ''status''.  Based on what's displayed (in the Putty terminal screenshot), it looks like I'm reading the data register at improper times???...However, comparing my logic analyzer info with the timing diagram on page 15 of the

Posted on May 28, 2018 at 04:16Hi all, Recently, I am working on a IoT device in which MEMS accelerometer LIS2DH12 from ST is embedded. Accelerations from the sensor will be used in offline calculations. I am trying to do an error analysis but it seems that there exist no official releases of the non-linearity figures nor in the community. In some of the MEMS accelerometers from ST, eg. LIS331AL, they did mention the NL is 0.5%FS. I understand that these MEMS sensors are not supposed to be used in accurate measurements, maybe usually just as a reference of tilt angle but I still want to know how 'inaccurate' it is in my application. Maybe I really miss some official documents from ST  which states the numbers..... Information from ST people are highly appreciated, thanks#lis2dh12 #error-analysis #non-linearity

Posted on May 25, 2018 at 15:25Greetings,Currently in our wearable product we are using LSM9DS1 to get the 9-axis sensor fusion result which is quite good (interruption rate set to 238Hz).However we'd like to use a 6+3 solution to reduce the cost. Is there any recommendation on 6+3 solution to get a good 9-axis sensor fusion result?Thanks a lot.Thanks,Dennis

Posted on May 17, 2018 at 18:00Hello, I'm using the LSM303AGR, accelerometer and magnetomter, without any problems but now I would like to do some tests with the embedded temperature sensor and datasheet doesn't says much about it.Firstly could you please confirm the usage of the register TEMP_CFG_REG_A ?Writing 0xC0 to it, as specified by the datasheet doesn't seem to enable temperature measurements, however writing 0x80 seems to work.Then could you please clarify the interpretation of the data ? The value is stored in OUT_TEMP_H as two's complement but is there an offset to account for ?Finally, could this embedded sensor be successfully used to measure ambiant temperature ? Would we need to calibrate each device to obtain an accurate result ?Thanks for your help,Guillaume#lsm303agr

Posted on May 22, 2018 at 12:59I'm trying to do a compass using an LSM303DLHC sensor embedded in STM32F3 Discovery. I have prepared such a code which provides declaration and reading data from both accelerometer and magnetometervoid LSM303DLHCAcc_Config(void){         LSM303DLHCAcc_InitStructure.AccFull_Scale = LSM303DLHC_NORMAL_MODE;         LSM303DLHCAcc_InitStructure.AccOutput_DataRate = LSM303DLHC_ODR_200_HZ;         LSM303DLHCAcc_InitStructure.Axes_Enable = LSM303DLHC_AXES_ENABLE;         LSM303DLHCAcc_InitStructure.BlockData_Update = LSM303DLHC_BlockUpdate_Continous;         LSM303DLHCAcc_InitStructure.Endianness = LSM303DLHC_BLE_MSB;         LSM303DLHCAcc_InitStructure.High_Resolution = LSM303DLHC_HR

Posted on March 13, 2018 at 13:41Hi.At the MWC 2018, ST presented a demo with RGB camera and the VL53L1x with multiple measurement points on the live image. I got the evaluation boards this week, the datasheet and API manuals online for this device don’t have enough details how to operate this configuration for multiple ROI, I tried to work through this using the example code but the results does make any sense, the distance measurement seems to be correct but it’s similar on all of the pixels within the aperture even when I cover just half of the sensor.Did someone succeed operating the ROI to sense the distance in specific pixel within the aperture?I've developed a small test app for the multiple ROI, here i'm covering half of the sensor, as you can see all pixels returns around the same result:

Posted on September 29, 2014 at 09:33I'm testing a LIS3DH and set the FS bit to 00 (+/-2g measurement range).I get about 16600 at 1g. The datasheet says 1mg/digit. Then I found in another application note (AN3182) that the sensor uses 12 bits left justified values. This could explain why I get this result.Could anybody explain this?What value should I get if I activate the self test? The datasheet says 276 for Ax. So this should be 276x16 = 4416?I think the datasheet should need some rework to make things more clear.

Posted on May 21, 2018 at 12:15Hi, ST    We met some problem when used LSM303C. We operated LSM303C go to power-down mode after the module power on . Generally , the LSM303C current consumption is about 6 uA which isconsistent with the datasheet electrical characteristics table. But sometimes the current consumption would increase to 48 uA after the module power on. And it seems that the acceleration module didn't work well for reading  accelerometer Who_AM_I register to get 0x00 but not  0x41.  What may cause this phenomenon. Please give us some guide advice.     Our operating codes are as follow:void LSM303C_Init(void){I2C_WriteOneByte(lsm303_acc,LSM303C_CTRL_REG5_A, 0x40);//Soft reset user_delay_ms(10); I2C_WriteOneByte(lsm303_acc,LSM303C_CTRL