MEMS (sensors)

Hi, I am considering IMUs from ST and ADI - ADIS16505. I found that ADI provide their IMUs with "in-run bias stability" and "angular random walk", but ST does not. I also checkout the community about this, and ST only test IMUs in characterization. I find LSM6DSR characterization can be shared. I am looking at the LSM6DSV16BX IMUs characterization for the two parameters. Could you please provide that for my final decision? Thank you very much

Hello everyone, I'm looking for an application note (similar to AN5063 but for the LPS27HHTW sensor) to get an idea of the mechanical integration and any necessary tolerances. Additionally, I wanted to ask the community if anyone has installed two sensors on the same side of the board and what the mechanical implications are in this case.

I use LIS2DS12 This is my init function   void LIS2DS12_Init(void) { uint8_t ctrl_1 = 0x72; //0111 for 6.4kHz ODR [7:4], 00 for 2g [3:2], 1 for high frequency available[1], 0 for BDU not activated [0] uint8_t ctrl_2; // [6] for soft_reset, [1] for disable I2C, [0] for 4 wires SPI HAL_StatusTypeDef ret; ret = spi_read_LIS2DS12(CTRL2_ADDR, &ctrl_2); ctrl_2 |= 0x42; // [6] for soft_reset, [1] = 1 for disable I2C, [0] = 0 for 4 wires SPI ret = spi_write_LIS2DS12(CTRL2_ADDR, &ctrl_2); //reset the accelerometer ret = spi_write_LIS2DS12(CTRL1_ADDR, &ctrl_1); //set the accelerometer to measurement mode spi_read_LIS2DS12(CTRL1_ADDR, &ctrl_1); spi_read_LIS2DS12(CTRL2_ADDR, &ctrl_2); }   with read and write :    HAL_Statu

Hello,I am working with the LSM6DSV16X IMU sensor and interfacing it using SPI mode 3 on an STM32 microcontroller(STM32F446RE) with STM32CubeIDE. My SPI configuration is set with CPOL = High and CPHA = 2nd edge, and I have set the baud rate prescaler to 4, resulting in a baud rate of 10 MBits/s.Before reading the WHO_AM_I register, I configure certain registers as follows:if (spi_write_register(CTRL3_REG, 0x45) != SUCCESS) return ERROR;if (spi_write_register(FUNC_CFG_ACCESS_REG, 0x00) != SUCCESS) return ERROR;However, when I attempt to read the WHO_AM_I register, I consistently receive 0x80 instead of the expected 0x70.Here is a summary of my setup and the issue:SPI mode: Mode 3 (CPOL = High, CPHA = 2nd edge)

Dear ST technical support.Please can you advise the pin configuration and bus timing (period between active devices) to allow me to connect three of your LPS22HB pressure sensors in parallel on the same SPI bus?The CS pin is used to enable the SPI function on one device but it is not clear if the other SPI pins can be common with other devices.Thanks and regardsDuncan

Posted on June 05, 2017 at 20:31Hi,We're using LIS3MDL to detect changes in the earth magnetic field due to various metallic objects flowing in the sensor proximity. So, we are not interested in the correctness of the absolute values in order to properly detect the magnitude of the field or the North direction, we only need to compare the magnitude of the field between consecutive measurements. That being said, I don't see any reason to calibrate the readings.The problem we are facing is that for unknown reason, the readings (mostly on Z axis, but I've seen also for Y) on some of our sensors are sometimes evolve from initial 'right after boot & install', normal values to really unexpected and different values. The external conditions are the same, the magnetic field is the normal earth field.Please have a look on this table, it's basically a log with recordings (x1, y1, z1 is the first measurement, x2, y2, z2 - second measur

I have an X-NUCLEO-IKS4A1 mounted on top of a NUCLEO-L476RG and I am trying to connect that to Mems Studio. I get one of the two errors in the attached screenshots. Either "Board not identified" or "Some device is already connected".

We embed lis3mdl on our board that we produce, most of them are perfect, unfortunately there are single pieces where the magnetic north is wrong, the heading is wrong by up to 60-100 degrees. What could be the reason ? Regards. 

As you can see, I was doing a test where I tried setting the gyroscope and accelerometer to power down mode and gave it a 10ms delay, which I called time 1, while I again turned the gyroscope on The accelerometer is set to high-performance mode, and a 70ms delay is given to the data again. This time is called time 2. After exiting, I start reading the data. At this time, the data is read normally after leaving this code, but between time 1 and time After the time of 2 is changed (only the time becomes shorter), the read data will have data errors for a long time. I would like to ask you for some advice. At the same time, time 1 and time 2 are 300us and 70ms respectively in the manual. Want to know why there is such a big discrepancy? Below is my code. Thanks，  

Hello, I am trying to interface a TI MCU with three LSM6DSV16X sensors using SPI communication on the same bus. My setup consists of 3 chip select lines with a 10 kΩ pull-up resistor (on all sensor boards), POCI (MISO) with a single 10 kΩ pull-up resistor (on 1 sensor board), PICO (MOSI) and the CLOCK line with nothing, with a long distance shown on the schematic (attached file). All sensors are powered with 3.3V. I am facing an issue that I can't solve. This setup seems to be unreliable, as I can't consistently read all three chips correctly. My flow is as follows:Configure MCU to communicate in SPI mode 3 with 1MHz frequencyGlobal reset of the device (writing 0x04 to FUNC_CFG_ACCESS)Wait 100ms (more than the application note, for some reason 30ms doesn't work every time)Read the WHO_AM_I register For some reason, most of the time I can read 0x

Hello Developers,We are developing a predictive maintenance application using ST Mems IIS3DWB sensor with out custom board having Cortex-M4 archichtetcure. Currently we have integrated Motion SP middleware to perform time domain analysis. But as the values are not that accurate with the refernce device readings, so we are trying to calibrate ST Mems IIS3DWB using ST's Motion AC calibration library on our custom board. So we have added the library file in our project, but on enabling the Motion AC library using initialise function the firmware gets stuck.  So i would like to know whether Motion AC library run only on STM32 based boards ? Can the source file be made available for the same for porting it on other platforms ? Also is there any other way of calibrating IIS3DWB sensor.     

I have an application using the XL function, it works fine, no issues.Now I need to read the gyroscope output data.After I finish configuring the registers:CTRL9_XL 01INT1_CTRL 03INT2_CTRL 06CTRL1_XL 30CTRL2_G 32CTRL3_C 04CTRL6_C 80CTRL8_XL 00MD1_CFG 02MD2_CFG 02CTRL9_XL 01I get the 1st interuption. I read the status register and both GDA and XLDA are set.Then I read XL data, followed by gyro data. So far so good. My problem is that I keep getting interrupts for XL but reading the status register, GDA remains 0. I tried to read gyro output but it never changes.Is there something I'm missing?   

Hello,we would like to use the LPS22HHTR barometer sensor in a new product. Now it is not clear from the datasheet how the sensor should be placed in the housing. I have not found a design guide for this product. Are there certain requirements regarding the distance between sensor and housing wall, minimum volume between sensor and housing wall, requirements for the opening used in the housing (e.g. for membranes used, etc.)? Thank you for your prompt feedback. Best regards, Pascal

Good morning,I am having issues with the INT1 pin on the LIS2DH12. I have been trying to make it to work for Watermark, Overrun or ZYXDA, but none of these events trigger any interrupt on the INT1 pin. When polling the Watermark Level, the FIFO Overrun or the new data available register though, I can see that they are working as intended.Here is the configuration code, in case it helps or anyone can see an issue: lis2dh12_block_data_update_set(&dev_ctx, PROPERTY_ENABLE); /* Enable Block Data Update. */ lis2dh12_data_rate_set(&dev_ctx, LIS2DH12_ODR_5kHz376_LP_1kHz344_NM_HP); /* Set Output Data Rate to 1Hz. */ lis2dh12_full_scale_set(&dev_ctx, LIS2DH12_2g); /* Set full scale to 2g. */ //lis2dh12_temperature_meas_set(&dev_ctx, LIS2DH12_TEMP_ENABLE); /* Enable temperature sensor. */ lis2dh12_operating_mode_set(&dev_ctx, LIS2DH12_LP_8bit); /* Set device in continuous mode with

Dear Forum. I use a LIS3DH connected with a Pic mainboard. I cummunicate with I2C and have set it up with interupt. I use 8mg, Lowpower and 50 hz odr. I have a problems with Power Consumption. Before i insert the LIS3DH it use 3 microampere. After i have set it up with interupt i use 100 microampere. We use a STEVAL-MKI105V1 eval board. How can i set it up so it only use 10 micro ampere.    Best regards Bjarne Profort. 

I use the continuous mode of FIFO and set the WATERMASK of FIFO to 2. Then, I route the FIFO threshold interrupt to INT1. In theory, for each set of XL+GY data generated, an interrupt should be generated. Then, I can read a set of XL+GY data in the interrupt handling function. In practical operation, it was found that when a second interrupt was generated and data was read, no new interrupt was generated.The following is the waveform of the INT1 pin that I captured：   Part of the code is as follows:asm330lhh_fifo_sensor_tag_get（&dev_ctx， &reg_tag）;{  if(GPI

Hi,I've connected to my Pico via SPI1 an STEVAL-MKI208V1K board with an IIS3DWB vibration sensor and I want to read data from it.I want to compile this driver for RPi Pico RP2040 using VSCode, can I do that? Can I port STM32 C lib for PICO RP2040?

Hi I was looking at how a register read works for LSM6DSLhttps://www.st.com/en/embedded-software/stsw-fcu001.htmlI found the function below. Does the number/amount of __asm("dsb\n") correspond to SPI clk?Is there no easier way to do this? Like using HAL_SPI_TransmitReceive(...)?  /*** @brief This function reads a single byte on SPI 3-wire.* @param xSpiHandle : SPI Handler.* @param val : value.* @retval None*/void SPI_Read(SPI_HandleTypeDef* xSpiHandle, uint8_t *v

Hello,I try to use LIS2MDL embedded temperature sensor value, thru TEMP_OUT_L_REG and TEMP_OUT_H_REG. Data is signed 16-bit byte in 2’s complement and 8 LSB / °C. The four mostsignificant bits contain a copy of the sign bit.At room temperature I read 0xFE20, so it is negative, so I convert in positive value with 2’s complement : NOT(0xFE20) + 1 = 480 in decimal. Then I div by 8 and I find 60, so -60°C.What is wrong ?ThanksBest RegardsThomas

Hi,I have STEVAL-MKI109v3 board and steval-mki186v1 sensor. I need some source code or library code which I can use to write a application which meets my requirements. And I also want to know which IDE I should be using to write the application so that I can flash the application on the the evaluation board. Will I be able to use the USB for flashing the code.Please provide some links which might also be useful in learning about the example codes.​Thanks,Akhil​

Hi All,We are implementing a custom PCB which includes an ISS3DWB which sits alongside an EEPROM chip on the same SPI bus. The bus master is a STM32F405. The design will has separate CS pins for each device, chances are the EEPROM will only be communicated with every so often and the primary use of the SPI bus is to get the acceleration data from the IIS3DWB.When the CS pin of the IIS3DWB is held in idle (high) does the SDO pin go high-z and allow other devices (in the case of a multi slave SPI bus) to take control??I know the EEPROM we have chosen (25LC1024) will work on a multi-slave bus.Any pointers would be much appreciated.Cheers all! 

Hi there,After playing around with basic examples for the lsm6dsox sensor i am trying to fine tune its functionality to my exact needs. However the datasheet seems to lack information on these:#1: Does writing the SW_RESET bit of CTRL3_C register reset all the register values to their default values mentioned in table 21?#2: What does this quotation mean: "It is possible to select decimation for timestamp batching in FIFO with a factor of 1, 8, or 32."? (I know what decimation means in general, but not sure what it has to do with timestamp values of the lsm6dsox)#3: What do batch data rates of the gyroscope and accelerometer mean in FIFO_CTRL3 register? 0 means each value is written to the FIFO as soon as sensor output is available? Does batch data rate need to be the same as ODR? Or if batch frequency is 2xODR, then it means that sensor output data is dumped into the FIFO every 2 seconds (in which case there must be some add

I am writing a custom linux driver module to be able to read accelerometer and gyroscope data from the LSM6DS3 FIFO in blocks.I have set the fifo watermark to 512 words, ODR for accel, gyro and FIFO both set to 416Hz. Scale 8G and 250dps. As there is no interrupt line connected to our CPU, the driver polls the FIFO_STATUS2 register every 100ms to check if the FTH bit is set. When it is, it reads the FIFO_STATUS 1/2 to get the number of words in the FIFO, then reads the initial pattern# from FIFO_STATUS3/4. It then reads the entire FIFO in one read to improve efficiency over reading pattern# then 2 bytes FIFO in a loop. I make sure I only read the FIFO in a size that is a multiple of 12bytes (6 for gyro and 6 for accel) so full samples are read.Often after a few seconds, there is missing data in the block from the FIFO. An example follows:            

Hi,I'm using the IIS3DWB accelerometer to get triaxial waveform.I just want to know what is the best approach to detect over range.I tried to compare sample by sample in each channel with the maximum possible positive value (>32766) and the maximum negative value (<-32767) but I didn't get overflow detection when the peak acceleration > range.When I set the limits to +/-16384 (half) my detection routine works (with an instantaneous acceleration value > range/2).What is the measured acceleration value when the acceleration is over the full-scale range?Does the accelerometer limit the the value to the maximum?Best regards 

Could you please provide information about the output data rate (ODR) for the IIS2DLPCTR accelerometer?For example, if I want an ODR of 50Hz in High Performance mode, with BW=ODR/2, how accurate is the 50Hz ODR?  Similarly, if I use the single data conversion on-demand mode at 50Hz, what would the accuracy be (assuming a perfect 50Hz trigger on INT2)? Thanks.