MEMS (sensors)

Hello STM Community,I am working with the STHS34PF80 presence detection sensor on an STM32WB55 development board, and I've encountered an unexpected issue with its detection behavior.Problem Description:When an object like plastic or paper passes in front of the sensor, it does not detect the object's presence, which I understand could be due to these materials not emitting enough infrared radiation. However, the problem occurs after the object is removed. Once the object is no longer in front of the sensor and there is no one around, the sensor unexpectedly detects a "presence."Observations:The sensor detects human presence accurately.The false presence detection only happens after an object (plastic, paper, etc.) is moved away.There are no obvious environmental changes (such as temperature shifts or airflow) when the false presence is dete

Hi.I'm an intern working with the SensorTile.Box Pro for a project. As the subject suggests, I was wondering if the mobile app provided with the box could be modified, and if so, how?May sound like a dumb question, but I saw that the source code for the app on Github required an SSO authentication somewhere in the gradle files. I have little experience with such things and would appreciate if someone who knew more about this could help.The purpose of the modification was to change the GUI of the app among other things, such as triggering an SMS message when a specific event occurred.

I'm using the LIS2DW12 accelerometer to detect and classify different types of vibrations. I need to configure a wake-up threshold for a specific scenario.Two questions:1. When the sensor is set to 2g and I use the WK_THS[5:0] configuration, setting the register to 000001 corresponds to 2g/64 = 0.0312g. However, I'm trying to determine what this value represents in the recorded signal, which appears to range from 2048 to -2048. Does WK_THS[5:0] = 1 correspond to 0.0312/2 * 2024 = 31?2. Additionally, since the sensor may be mounted with a tilt, I’m considering applying a High Pass filter. Is this the correct approach to remove the DC/Tilt and ensure th

Hello Community,I am trying to implement a basic FFT computation on our STM32G0 MCUs using MotionSP for a 16-bit accelerometer signal.I am not sure why does MotionSP by default uses float32 for FFT when the original sensor signal is 16-bit?Can I then simply reconfigure the data type in the MotionSP by changing the float32 to q15?Kindly guide, as we do not have FPU to compute float32.Also, does a 16-bit sensor output requires a float32 FFT?@Eleon BORLINI 

Hello,I'm trying to disable temperature compensation on the lps22hh sensor, does anyone know if there's a specific register i can manipulate? Thanks!

Hi Sir, Can the LPS27HHW be used to detect non-water liquids, such as oil?  

Good afternoon!  I used an example from the link https://www.st.com/en/embedded-software/fp-ai-predmnt2.html   However, the card does not connect to the cloud, I have already downloaded the certificate and private key and it gives an error.           

Hello all,I am looking for more info on the gel used with ILPS28QSW.We want to use it in an application where the sensor may be submerged in 10% to 40% alcohol v/v for extended periods of time. Will the sensor be okay? Or is there another product which is more suitable for this application?Thank you,Regards,ShrinathN

Regarding the sensitivity of IIS3DHHC, the datasheet says 0.076mg/digit. It is written. To be exact 5g/2^16 (= 0.07629mg/digit) Is that correct?Thanks!

I am using the STHS34PF80 sensor with the TMOS10-12030 lens from Fresnel Factory. Does anyone have the transmittance % for wavelengths 5um-20um?Thanks

Hello there, I am currently working on a project where I am prototyping STM32WL55 with an STHS34PF80 sensor to detect the presence. The presence detection is excellent and robust so far. However, the power consumption seems to be very high at the moment. I am using Nordic Power Profiler Kit II to measure the power consumption of the STHS34PF80 sensor and it's around 350 microAmps. I am using Power Profiler as source mode sending 3.3v and measuring current consumption on the sensor. The TMOS Sensitivity is set at 2, AverageTAmbientNumber is at T_1, Block update is false, and TmosODR is running at 4Hz. I am using the Arduino framework to run the overall system and the sensor is purchased from Sparkfun (https://www.sparkfun.com/products/22494).   The power consumption is very high considering the sensor runs 24/7 and inte

I'm working on the IIS2DH and I came to plot the system response at various frequencies depending on the high-pass settings (12, 50 or 100 Hz) with ODR = 5372 Hz, FS = +-4G, input signal 2.82g sin wave (2g RMS). Surprisingly it seems that in the passband not all filters have the expected 0 dB gain, the higher the cutoff frequency the lower the inband gain, as seen below:Is something that is expected for this sensor + digital filtering? What type of digital filter is implemented? I found no traces on this in the datasheet.All informations much appreciated.Thanks in advance

Hello ST Community,I'm currently working with the STHS34PF80 sensor for presence detection on an STM32WB55 development board. However, I've encountered a couple of issues that I hope someone here can help with:Short Detection Range: The detection range without any lens is quite limited, averaging around 1 meter. This is significantly shorter than what I expected for my application. I’m wondering if others have experienced similar range limitations and if there are any suggestions or adjustments that can improve this.Stuck Presence Flag in Register: After a presence is detected, the presence register value maintains a fixed high value even after the object has left the sensor’s detection zone. This causes the presence flag in the function status register to remain raised and not get cleared automatically. As a result, I am unable to reliably use the presence detection for further processing because the presence f

Hello ST guys:We have used LSM6DSV FSM function and LSM6DSV supports 4 external sensors. We have seen that SINMUX command is used to change the input source for FSM as follows:But which one of four external sensors will be chosen to use for FSM? How to implement this function for FSM and could you give us any good suggestions? Thank you very much.BRs.

I am not able to pair Sensor Tile.Box Pro with my iphone 13 over Bluetooth with the app ST BLE Sensor. When connecting I get prompted to enter number shown on the device, but the Tile.Box does not have a display, so that’s impossible. 

Hello,     I am developing on a custom boards with a STM32F407, LSM6dsv16x and LIS2MDL.On CubeMX I set the MotionFX package. Even selecting the MotionAC it looks like the library is not added to the output (is it correct?). The motionTL can be added. If I would increase the inclinometer by performing a factory 6-points calibration of the accelerometer, is the MotionTL the solution?On a previous board we used LSM303ARG we measured the 6 points, performed the Matrix calculation off-line.  Does the library compute the transform Matrix? Thank you.

Hello,I'm working on a BLE server using the STEVAL-STWINKT1 board and the STSW-STWINKT01 package , and I'm encountering issues with the GATT characteristic write operations, particularly for controlling an LED.Setup:Board: STEVAL-STWINKT1BLE stack: Using the ST BlueNRG BLE librariesGATT DB: The GATT database includes a characteristic to control an LED (LedCharHandle).Functionality: I'm trying to control the LED on the server side using write requests from a BLE client.Problem:The BLE client sends a write request to the server (STEVAL-STWINKT1) to toggle the LED. However, the write request either isn't received or isn't processed correctly by the server.I've verified that the Write_Request_CB function is implemented and checks the correct handle (LedCharHandle + 1). It attempts to read the data to control the LED, but the LED control functionality isn't triggered as expected.Key Code Sections:Here i

Hi,    I am using ASM330LHB in my project. ASM330LHB has only built self test which can only executed during power on to see ASM330LHB is healthy or faulty? But during runtime (device working in dynamic conditions) there is no way to find ASM330LHB is healthy or faulty?1. Please suggest a method to find ASM330LHB is healthy or faulty during runtime?2. Is ASM330LHB is fully calibrated against over its temperature range?Thanks in advance,Pavani.  

When STHS34PF80 detects the human body for a period of time, TPRESENCE cannot fall back normally, and pres_flag is always 1。 code：

I'm using LSM6DSV, and use it wake-up funciton, I will configure registers when wakeup, that time I got some invalid data such as "1.998665088 1.998665088 1.998665088", how to avoid it?

From theory, we define a Finite State Machine (FSM) as an abstract machine that can be in exactly one of a finite number of states at any given time, and is composed of a START state, a STOP state and a series of states, conditions and transitions. But how is this definition practically implemented in LSM6DSO sensor?For the LSM6DSO sensor, FSM is intended to detect a specific gesture: there are up to 16 independent state machines, both XL and G (and external MAG sensor) data can be used, and a number of interrupts and source registers for the event detection management are available.The activity recognition spans from Free Fall, to Glance, to Flip up and down, passing through Pickup, Shake and Wrist Tilt.If you are interested in a detailed explanation of the LSM6DSO FSM structure, that enables you to develop your own machine, please follow the next posts!

Hi,I want to compensate for the temperature of the LPS22DF sensor.how does one go about programming for it? Is this formula correct?Pcorrected​=Pmeasured​−(TCF×(Tmeasured​−Treference​))If it is, should I use a temperature reference value of 25°C?Also, can you tell me the value of the Temperature Compensation Factor? Can I make a correction formula with TCO(Temperature coefficient offset) with a data sheet and program it?If possible, please let me know the formula that I can use TCO Thank you

Hello,    I am working on a custom board based on STM32F407 CPU with the LSM6DSV16XTR accelerometer+gyroscope and LIS2MDLTR magnetometer.The aim is to get board inclination and compass information with the maximum accuracy.The MotionFX library seems to work fine but the data from magnetometer are not correct since it requires calibration. On CubeMX even if I select the MotionMC software package, the MotionMC library is not added to the output.  I supposed this happen because the Magnetometer calibration functions are already available on the MotionFX library. The MX_MEMS_Process() is called from a FreeRTOS task, SensorReadRequest is set to 1 from a timer as done in the application demo. The problem is that MotionFX_MagCal_getParams(&mag_cal_data_out);does not update the mag_cal_data_out variable. All the hi_bi

Dear forum,We plan to assemble five LPS22DF sensors on the same I3C bus and (off course) to address them individually. According to the datasheet (7.4.1 MIPI I3CSM CCC supported commands) the answer to GETPID can only have two values, depending on SDO state. Beside that answer to GETBCR and GETDCR are fixed. As far as we understand Dynamic Address Assignment of the I3C protocol, there is an issue.We cannot use the I2C static address, because again it can have only two values, depending on SDO state.We cannot use Enter Test Mode (ENTTM) command, because it is not supported by the LPS22DF. (Even if we could, we might have 5 different random values in the Provisioned IDs, but it would not help so much to identify each sensor.)Thank you in advance

hi!I have a problem with the calibration of the IIS2ICLX-Accelerometer. I see there is happening a calibration but because I make a sensor fusion in the next step, I want to have the calibration fixed once its done. In the data-sheet and the forum I couldnt find a solution. Is there a possibility to manually control the background calibration process?Thanks!