MEMS and sensors

Posted on October 16, 2016 at 11:59The LIS3DSH has a three channel 10 bit A/D converter but I can't find any information on it. What is the accuracy? (I could tie one channel to a voltage reference for calibration if necessary) What is the input voltage range? What is the maximum input current? (will I need to buffer the channels) #lis3dsh

How do you turn the VL53L4CX extended mode on in python3 ??

Hi, community,   I have a bespoke board running an rp2040 and have been coding the LSM6DSO from the spec, along with using web-found python and cpp examples as starter code. There are several things I haven't found enough detail on and would like help.  1. if I read 2 byte temperature from the fifo data address, do I have to still read the full 6 bytes from the fifo data register and toss the 4 unused bytes, to keep the fifo syncronized with 6 byte data reads? Or can I read 2 for the temperature tag, then read 6 on the next gyro or acc tag? 2. how do I uncompress compressed data from the fifo? The only reference I could find leads to a dead URL. And same thing, if compressed, do I still need to read 6 bytes? Related to that, the driver cpp code on github seems to be empty, as if it was once there but was removed. 3. How do I decode the fifo timestamp info? thank you,   bob s

Hello,I am trying to get the temperature from LSM6DSVX sensor. Accel and gyro are working well but I can't get the temperature. The buffer cannot be enable for temperature. It works for Accel  and gyro buffer can be enable.their is something specific to do for the temperature ?  cmd line :echo 1 > /sys/bus/iio/devices/iio:device3/buffer/enablereturn : write error : invalid argument.

Hello Team ST and Community,I have following code for step count for our wrist-based device. We use LSM6DSO IMU.The step debounce threshold has improved the step count accuracy. It is currently set to 20. But, I could not get rid of the false positives. It also counts steps when I am typing on a keyboard and other minor movement when it exceeds step debounce threshold (e.g. typing more than 20 characters will start step count).I tried setting delta time period to mitigate this issue but it does not help a lot. Therefore, I have two question.1. Am I programming delta time period correctly? My understanding is that a step interrupt would be generated if a step movement happens between 256ms and 512ms as shown in the code. Please correct me if I wrong.2. How can I reduce false positives from minor movements? The false rejection advanced mode option is not that accurate to reject minor movement. Thank you,Aakash.  //Step counter interrupt lsm6dso_pin_int1_route_get(&amp

Hello, In general, I would like to better understand the relationship between the sampling frequencies of the FIFO and the Accelerometer (ISM330) and how to adjust them correctly for my application, could anyone give an example? In my case I have the following configuration:ISM330DLC_ACC_SetOutputDataRate(&MotionSensor, 26.0f)ISM330DLC_FIFO_Set_ODR_Value(&MotionSensor, 6660.0f)ISM330DLC_FIFO_ACC_Set_Decimation(&MotionSensor, ISM330DLC_FIFO_XL_DEC_32)That is, the ISM is sampling the accelerometer at 26Hz, the FIFO with decimation is configured to store at a sampling of approx. 208Hz (6660/32), which indicates that in 1 second the accelerometer saves 8 samples (208Hz/26Hz) from the accelerometer in the FIFO. Is this correct? For a practical application, for example, a motor with 1000RPM (1000/60=16Hz), would the frequency I need to adjust in the ISM330DLC_ACC_SetOutputDataRate function be at least ISM330DLC_XL_ODR_52Hz? Your feedback is much appreciated.Re

Can someone help me how to use one interrupt pin for Activity/Inactivity and another for Free Fall detection? I need to use it in the lowest possible possible mode as my device is coin cell battery powered.Regards,Asish Banerjee

Hello,  I am trying to detect Single & Double tapping on LSM6DSL accelerometer. I am configuring the relevant registers as follows: CTRL1_XL=0x60TAP_CFG=0x8ETAP_THS_6D= 0x8INT_DUR2=0x45WUP_THS=0x80MD1_CFG=0x48 Every time I tap the accelerometer, and interrupt is generated and the I read the TAP_SRC register to identify the type of the type. The  X_TAP, Y_TAP and Z_TAP  bits are updated properly. But I NEVER get the SINGLE_TAP and DOUBLE_TAP bits set - They are always ZERO. Can someone please help me what am doing wrong? Thanks

I am trying to get the an values ready interrupt working, but I cannot seem to find the right configuration of registers. Normal threshold interrupts are working as expected.After the normal setup and using all different speeds ODR, when setting INT1_CTRL to INT_DRDY_XL active, I do not get any interrupts. The oscilloscope shows no change as well on either H_LACTIVE as well. Is there a sample that can be provided which has a working implementation of the interrupt working? So far all public sources have non working code. As an MCU I am using an ESP32 and Arduino.Here is my current initialisation:// Enable accelerometerwriteRegister(0x1F, 0x38); // CTRL_REG5_XL - Enable XYZ axeswriteRegister(0x20, 0x60); // CTRL_REG6_XL - ODR 952 Hz// Set up interrupt generator and DRDYwriteRegister(INT1_CTRL, 0x01); // Enable IG_XL (bit 6) and DRDY_XL (bit 0)writeRegister(CTRL_REG8, 0x00); // Active HIGH, push-pull 

Hi,We are intending to use AIS2IH for one of our projects.We would like to change some settings while the device is running and see their effects on the performance/power consumption, in order to decide the best settings for our purpose.I would like to ask if we can change the below bitfields on the fly. If we can not, could you please provide the steps to change them correctly?CTRL1 register:ODRMODELP_MODECTRL6 register:FS (full scale selection)LOW_NOISEKind regards,Kerem

Currently, I'm working on a project to detect human height, but the measured height appears shorter under strong ambient light. I would like to know if the ambient light affects the distance measurements

We placed two VL53L1X sensors at 18.6" in our temperature chamber. Over a 50C swing we saw up to 1.15" of variability. In the images bellow the chamber temperature stabilized around 30 minutes. The target was a large 24x24 sheet of white nylon 0.5" thickThe sensors were left on the entire time, polled every 10 seconds.SPAD ARRAY size 8x8Is there any way to improve this? Is it possible to access the temperature registers on the VL53L1x so we can create a variable to compensate for the temperature induced error?  

Hi, I am trying to integrate the VL53L8CX ULD driver with a project that utilizes chibios on an F4 based board.The TOF sensor firmware seems to be about 86KB. For a transfer of this size, the device fails to setup and use DMA-safe bouncebuffers. I cannot get it to transfer more than 9865 bytes at once. Can the VL53L8CX_WrMulti(...) calls be broken down into smaller chunks as a work around? If I understand correctly, this is using the auto increment feature of the I2C bus. So to further break the VL53L8CX_WrMulti(...) calls, I will have to ensure the address for each call is sent appropriately. So will this work?//in vl53l8cx_init(...)status |= VL53L8CX_WrMulti(&(p_dev->platform),0,(uint8_t*)&VL53L8CX_FIRMWARE[0],0x2000);status |= VL53L8CX_WrMulti(&(p_dev->platform),0x2000,(uint8_t*)&VL53L8CX_FIRMWARE[0x2000],0x2000);status |= VL53L8CX_WrMulti(&(p_dev->platform),0x4000,(uint8_t*)&VL53L8CX_FIRMWARE[0x4000],0x2000);status |= VL53L8CX_WrMulti(&(p_dev-&g

HiI'm trying to use two ISM330IS sensors both connected to the same external microcontroller.I want to synchronize accelerometer and gyroscope sampling (and the ISPU) to the processing cycle (1ms) of my controller.They should optimally both start the sample at the same time, triggered by a pulse from the microcontroller connected to both the sensors.I'm not 100% certain if this is actually possible. In AN5850 the INT2 pin is described like it may be used for this purpose (I²C master external synchronization signal (MDRDY)). It is described that this pin can be used to externally trigger sampling of the "sensor hub", which is a number of optionally connected I2C sensors. The description in section 6.2.1 of AN5850 is:"When this bit is set to 1, at least one sensor between the accelerometer and the gyroscope has tobe active and the sensor hub trigger signal is the INT2 pin"Does this mean that I can use a pulse on the INT2 pin to trigger sampling of the gyro and accelerometer, or

Hi,I'm working on a prototype of a device. One of this device features is to collect data from gyroscope, accelerometer and e-compass. It is very important that the device will be ultra-low-power. One goal for the prototype is to verify how much energy will that device consume.I have a question about components which I could use to build this prototype. I'm going to use STM32 NUCLEO-L432KC which will provide me ultra-low-power MCU. Is there any evaluation board with sensors (accel, gyro, e-compass) which I could connect to the Nucleo board?

Hello,I once compared your eCompass application (STM32F401RE/X-NUCEO-IKS01A3) with the compass on my smart phone.The compass on my smart phone behaves much better than the ECompass; it is not affected by rapid changes in the angle of inclination or by vibrations.What is the reason for this? Is it due to the sensors or the software?

HIWhen using the FIFO mode on the lsm6ds3tr-c sensor, there appears to be an issue where occasionally the pattern value read from the FIFO buffer is incorrect, leading to potential errors in the subsequent data retrieval process. This issue also results in the possibility of erroneous FIFO data being read.ERROR 1：00> <info> app: level: 18, read_level: 1800> <info> app: pattern: 0, index: 0, count: 213525, raw: -100> <info> app: pattern: 1, index: 1, count: 213526, raw: -200> <info> app: pattern: 2, index: 2, count: 213527, raw: 700> <info> app: pattern: 3, index: 3, count: 213528, raw: -11900> <info> app: pattern: 4, index: 4, count: 213529, raw: -5200> <info> app: pattern: 5, index: 5, count: 213530, raw: -407000> <info> app: pattern: 6, index: 6, count: 213531, raw: 81500> <info> app: pattern: 7, index: 7, count: 213532, raw: -2867500> <info> app: pattern: 8, index: 8, count: 213533, raw: 000&gt

#define RANGE_ERROR_DISTANCE_BELOW_DETECTION_THRESHOLD 0x03#define RANGE_ERROR_OTHER 0xFFHi ST,Some of our production devices are receiving the above errors.  Can someone help me with understanding what might cause these errors?Thanks,Will 

hi i want to confirm can i use single vl53l3cx for depth mapping, i know that i should use l5,l7 or l8 but these not available in my country? and also since vl53l0cx the cheapest can i multiple of those too for the same?

There are three modes: LONG, MEDIUM, and SHORT. The names suggest that LONG allows measuring the greatest distances. In document UM2923 (section 5.2), there is information that the maximum distance can be achieved with the MEDIUM setting. What setting should I ultimately choose to measure the greatest distances?

I am currently working on modifying the sampling rate for the LSM6DSO32G IMU sensor in a Samsung Android kernel. After reviewing the device tree and sensor driver files, I noticed that certain parameters like odr (output data rate) seem to control the sampling rate. However, I am not sure of the exact steps to apply these changes and ensure that the modified sampling rate is reflected correctly in the system.Here are my specific questions:Which files in the Samsung Android kernel should I modify to change the sampling rate for the LSM6DSO32G?Do I need to make changes in both the driver source code and the device tree, or is one sufficient?Is there a way to dynamically update the sampling rate (e.g., via sysfs or a similar interface) without rebuilding the kernel?Are there any specific steps or precautions I should take to test and validate the changes?Any guidance, code examples, or references to related documentation would be greatly appreciated!Thank you in advance for your help.Best

Posted on March 13, 2014 at 00:22I am interested in the LPS25H MEMS barometer chip, but I am having a hard time figuring out the footprint of the HCLGA-10L package. Here is what is called out in the datasheet: I cannot decipher from his what the dimensions of the pads should be.  I believe that e1/2 might give me the width, but I cannot determine the length.  Maybe that's what B is supposed to mean, but I don't see it. Also, I found that there is a http://www.st.com/st-web-ui/static/active/en/resource/technical/document/application_note/DM00064026.pdf but cannot find one for the LPS25H.  I realize it's a very new part, but this would help -- it provides some guidance on how the pads should be laid out. Can someone more mechanically inclined parse this for me? Thanks. #hclga-10l

Hey Everyone,  I bought this sensorhttps://www.sparkfun.com/products/21325 and it is default to work as i2c. Which I do. I can read from this imu using regular polling, but I would like to use interrupts. But the issue is, interrupts to do not fire at all, I am not sure why. I am following the stm32 examples on githubhttps://github.com/STMicroelectronics/STMems_Standard_C_drivers/tree/master/lsm6dsv16x_STdC/examplesand I still have issues getting this sensor to work as an interrupt. Am I missing something? Do I need a pull down or pull up resistor on the interrupt pin? I worked with interrupts, theyre not difficult, but not sure why this specific sensor I cannot get to work.for example, what i am experiencing right now whether I go with fifo or data ready signal, the int pin is always high. It does not go low. I did put a pull down to see if I can bring it down, but even with a 10k resistor, the int2 in this example, is always high. I also checked status regist

Hi everyone, I have STM Nucleo-F401RE and X-Nucleo-53L7A1. I downloaded the SDK en.X-TOF1. When I check the pin configuration, I saw that X-Nucleo-53L7A1 I2C_RST (PB3) pin is SWO pin on F401RE board at the same time. I needed to delete PB3 pin configuration to connect F401RE board.  However, disconnecting PB3 did not allow me to communicate with ToF camera but I recognized that when I connect PWR_EN (PB0) pin and run the code I also lost debugger connection. When I disconnect the PB0 PWR_EN pin, the code runs but ToF sensor cannot be initialized. I am not sure if it is because Power consumption or not. Should I change pin configuration of SDK? What should I do to understand and solve the problem?

Hello everyone.I and my team are a bunch of BSc students in electrical engineering currently working on a gimbal project at our uni. My task is to prepare our IMU, the LSM6DSV16X by ST, for the readout of the game rotation vector so that we can get quaternions from it. The FIFO-Tag which should read 0x13 in the first five bits still reads 0x00, so there's apparently still no FIFO-Functionality enabled.I've used the ST-library found at https://github.com/STMicroelectronics/lsm6dsv16x-pid to implement the necessary functions and the platform_read and -_write funtions seem to work - I can send and receive signals and write to wr-registers and have the written bytes "stay there" as I've confirmed using oscilloscopes (measuring the MOSI and MISO signals alongside the clk and sc signals).The clk polarity is set to low and the clk phase to 1 Edge in the SPI configuration, just in case the problem lies there.Attached is the IMU's datasheet for easy reference as well as the init_imu() and valid