MEMS (sensors)

Posted on April 02, 2016 at 14:33Hi all!I've been testing for a few days the behaviour of the magnetic sensor and its interrupt capabilities. Offset registers simply are subtracted to the magnetic field measured on all of three axis and threshold register is the value after which the interrupt rises. If the chip has enabled interrupts on three axis the recognition interrupt rises only for the first magnetic field that exceed the threshold and once this happens others axis are ignored. If the interrupt rises for the z-axis, for example, the field on the x-axis can exceed threshold and interrupt don't rises.question 2: if i set single conversion and enable data ready interrupt, the status_m register is always read as 0 (not in continuous conversion). I'm excepting that data ready on x, y, z bit of the status_m register are set when conversion finished and interrupt rise (interrupt rise correctly). Why? #lsm303d-interr

Posted on April 01, 2016 at 15:37In rev.6 from http://www.st.com/web/catalog/sense_power/FM89/SC1449/PF262168 nothing about CTRL_REG2_A or how to set up an accelerometer interrupt. Tried to compare with LIS302DL documentation that at least explein what single or double click are, but still nothing about how to set up an accelerometer interruption. Is there valid and mature documentation ?

Posted on April 01, 2016 at 15:09Either from http://www.st.com/web/en/catalog/tools/FM147/CL1818/SC1528 or http://www.st.com/web/catalog/tools/FM147/CL1818/SC1528/PF260129♯ it is impossible to download the source code to port on STM32L4 and support LSM303AGR. Each time I'm redirected to a little flash based interface that looks Windows 3.1 era but remains empty. Is there a way to get the ZIP file of the source code ? #stm32l4-lsm303agr-inemoeng_m1li

Posted on March 31, 2016 at 08:19I need help to configure the interrupt, specifically for a 6d orientation interrupt. I have working as needed a light touch interrupt on any axis, but I also need sometimes to configure to interrupt only on a transition from out of the cone of z-positive then into that cone. I cannot find any explanation in the LSM6DS0 data sheet, nor any application note. I do see app note for LSM6DS3 here: http://www.st.com/st-web-ui/static/active/en/resource/technical/document/application_note/DM00157511.pdf But that does not help for this LSM6DS0 Also to note that I have both of these interrupts working on a LSM303D part. For both interrupts on LSM6DS0, I configure for 10-Hz and 2-g. For light touch on any axis, I

Posted on November 12, 2013 at 04:12I have used the LIS3DH for movement and angle detection for about 18 months. I now wish to use it for fall detection. Previously I ued another brand where you setup a register and get an interrupt when a zero G occurs in all axes for a certain time. I can see no way to do this with the LIS3DH but it advertises that it can be done. I can do it ''manually'' by continually reading each axis and setting a timer to record when it is continuously like this for, say 100mS. Is there an easier way that uses less power? Thanks

Posted on June 07, 2015 at 19:15Hi,For LIS3DH, the datasheet mentions two user programmable interrupts INT1 and INT2. Though config, threshold, duration etc. (INT1_CFG, INT1_SRC, INT1_THS, INT1_DURATION) registers are listed for INT1, no such registers for INT2 was listed in the register mappings. Is INT2 configuration and  functionality different from that of INT1? This was not clear to me from the datasheet or application note of LIS3DH. Please help.Thanks,Rihana #lis3dh #interrupt #int2

Posted on March 27, 2016 at 01:02I am running the LSM6DS3 in continuous FIFO mode capturing gyro and acc data. While collecting data I periodically pole to see if the water mark is met (96 words), and if so read out half of them (leaving some in the FIFO). Every once in a while (seeming randomly) the data seems to be misaligned, meaning all the data for one ''sample'' of 6 words is shifted. I get acc_Z in acc_Y and acc_Y in gyro_Z. The next read the data seems to be back to where it should be. How do I ensure the FIFO alignment during FIFO reads?I am running at 800Hz, no decimation, Acc and Gyro data, reading via SPI at full speed.  #lsm6ds3-fifo-alignment

Posted on May 06, 2015 at 13:02Hello, I have a quick question, and I cannot find answer anywhere on the web (including Reference Manual for MCU). I'm preparing for a new project, picking master unit, where one of most important feature is USB audio input (and if possible output). I already know that M3 based devices have too small buffers to run 96 khz / 24 bit so I went for STM32F429 (yeah, I know go big or go home, but I need extra SDRAM) with external PHY for max speed avaliable. However when I try to configure middleware with CubeMX for Audio Class with 96000 Sa/s i tells me that maximum frequency is limited to 48 ksa/s. Is it cubemx bug or usb core is really incapable of 24bit/96Khz mono input?/edit: I suppose it is CubeMX bug, therefore I posted in this forum. #audio #stm32f4 #usb #usb #cubemx #audio #microphone

Posted on March 23, 2016 at 20:47What's the difference between the two?

Posted on March 08, 2016 at 15:40Do you have any plans to release a version of this sensor with a smaller FieldOfView?As your presentation note you use a kind of diode matrix as photon input, do you plan to output the data of each diode to identify where the obstacle is?Per example at 2 meters with a 25degree FOV the obstacle could be anywhere inside a 0.44 meters radius circle. Is is good for obstacle detection but not for obstacle avoidance because a robot with 0.5 meters diameter can't move on a 0.7 meters passage because it will detect walls.  #vl53l0

Posted on February 23, 2016 at 03:21what is the maximum output power for laser?Regards,m

Posted on February 25, 2016 at 19:26Greetings.I am trying to get accurate gyro data out of the LSM6DS3, but my results are about 15% off of what I expect.  My test setup is a PASCO scientific Rotary Motion Sensor (RMS) with a LSM6DS3 mounted on top of it.I configured the LSM6DS3 such that full scale +/-32767 is mapped to +/- 1000 dps. I then rotated the RMS and LSM6DS3 at 366 dps (as measured from the RMS) and the LSM6DS3 gyro reported a z-axis rotational value of 10173.My calculated gyro z-axis rotational velocity for this value is 10173 counts * (1000 dps / 32767 counts) = 310 dps.Why is the gyro reporting 310 dps when it is being rotated at 366 dps? What is the guaranteed accuracy of the gyro?Thank you Scott Wild

Posted on March 17, 2016 at 07:15Hi! I am not getting anywhere near the Power Consuption specifications. I see a minimum power off 100uA, and no way to cut it down. According to documentation this device start in Power Down until any register is manipulated, and in that conditions, we see 100uA. Anybody idea what could be going on? I found this comment: ''I am betting that the LIS3DSH is like the LIS3DH and that the I2C address select pin has an internal Pull Up resistor.  Since you are grounding that pin you have an extra current flowing through that pin.  We confirmed this on the LIS3DH.'' Could this be the problem?

Posted on March 16, 2016 at 19:01LSM6DS3 has a dedicated register for the timestamp like -> TIMESTAMP1_REG (41h)/TIMESTAMP2_REG (42h) .But apart from this sensor how can the time stamp of a every data sample be captured of any sensor.By reading the system timer when the drdy interrupt comes for each sample while using in interrupt mode  or by reading the system timer when reading the data sample synchronously.Any reference will be highly thankful ! #accelerometer #lsm9ds1 #lsm303c

Posted on March 16, 2016 at 17:15The LIS3DH works from 1.8V to 3.6V.If I use it direct from a CR2032 coin cell w/o regulator, will there be any side effects as the voltage drops from 3.3V to ~2.2V?For example, will the calibration drift substantially?Is the drift something that I can adjust for in FW?If other devices on the same VCC cause the VCC to drop 0.1V to 0.2V over ~ millisecond (but still > 1.8V) , can this cause false triggers on the LIS3DH?I am not using the ADC, only the accelerometer.Thanks #lis3dh #accelerometer #cr2032

Posted on July 22, 2015 at 14:08All:Is there I2C example code that can be used with the STM32F4 Discovery Board to connect to the LPS25H module? I am running the processor at the full 168 MHz, and as far as I know, I have initialized the I2C1 port correctly. I have been trying to do the simplest thing - read the WhoAmI register, and I am not really sure what I should be inserting after even the I2C_GenerateSTART() function. How much delay is needed after initialization until generating START?Can I2C_CheckEvent() be used after START to check for condition before sending I2C Address? Lots of questions that could be solved by example code...AN4450 App Note mentions in section 6.3 that there are examples, but is there a specific example to ''get started with LPS25H?''Regards,Todd Anderson  #stm32f4 #about-lps25h

Posted on March 15, 2016 at 17:48The LIS3DH works from 1.8V to 3.6V.If I use it direct from a CR2032 coin cell w/o regulator, will there be any side effects as the voltage drops from 3.3V to ~2.2V?For example, will the calibration drift substantially?Is this something that I can adjust for in FW?If other devices on the same VCC cause the VCC to drop 0.1V to 0.2V over ~ millisecond, can this cause false triggers on the LIS3DH?I am not using the ADC, only the accelerometer.Thanks #lis3dh #accelerometer

Posted on March 15, 2016 at 10:29Hi Guys,I need to print XYZ axis data whenever their is raise in INT1 with FIFO buffer. And one more thing i'm getting temperature and XYZ data without INT1 but those value are in hexadecimal how can i get in normal temperature in C/F. and xyz in +- value in decimal format. I'm using ODR 1Hz with normal mode with FS@16g #lis2dh12

Posted on March 11, 2016 at 07:21There is a problem with LIS3DSH scale offset. We calibrate our devices for 1000 mG and -1000 mG, using raw data from accelerometer. After 1 month warehouse storage at room temperature, difference between values is still 2000 mG, but values are, for example, 991 mG and 1009 mG. Raw data have offset too. What could be problem?

Posted on September 17, 2015 at 15:47Hope that this is the correct forum section for my question. I have some strange problems with my IME002V1 evaluation kit. When I change some register settings in the Eden application and press write all registers I get the Ok message. When reading back the registers they are all FF, nothing is stored. Pressing write and verify all registers will give an error SET03(191 !=255) on all the devices. Downloaded the latest version of Eden 1.2.16.14255 and flash the firmware with 1.00. Anybody a clue why it's not working.

Posted on March 09, 2016 at 05:26Hi. I have connected an L3G4200D to an ATMEGA328P via SPI.WHO_AM_I gives me 211d, or 0xD3, which is the expected value.The values I use for control registers are:CTRL_REG1: 0b00001111CTRL_REG2: 0x80CTRL_REG3: 0x00CTRL_REG4: 0b10000000, but also tried with 0x00CTRL_REG5: 0x00My SPI parameters are:MSBFIRST, MODE3, CLOCK_DIV8Every time I power up the system, I get constant values coming out of X, Y and Z.These values are random. When I power cycle, they change, but keep constant while power is on.WhoAmI is consistently 211d.Do you have any idea what is going on? I also have a LIS331 accelerometer attached to the same ATMega328P, which is functioning well.I tried desoldering the gyro and desoldering it in place, but got no change in behaviour.

Posted on March 10, 2016 at 00:27Section 5.1 of the datasheet explains how to use the activity/inactivity block. However the register description:8.3 ACT_THS (1Eh)Activity threshold register (r/w). Its value is fixed at 0x00. Inactivity threshold I have a little trouble making any concrete sense of that section. But it somehow indicates that although this register exists it is hardwired to 0? What exactly is going on with ACT_THS and ACT_DUR? Thanks, Jon Pry

Posted on March 08, 2016 at 10:56 Hello ,everyone. Now, I have some prolem about LIS3DSH . I tried run ''state machine'' LIS3DSH presets WakeUp from AN3393 page 78, but anything I do, the interrupt occur on INT1 all the time. What is the Problem ? These codes debug on my device:   LIS3DSH_GetWHO_AM_I(&tmp); printf(''whoamI?.........\r\n''); if(vtmp==0x3F) printf(''IamLIS3DSH(0x%d)\r\n'',tmp); else printf(''Iam???~\r\n''); LIS3DSH_WriteReg(0x21,0x01); LIS3DSH_WriteReg(0x23,0x48); LIS3DSH_WriteReg(0x20,0x67); LIS3DSH_WriteReg(0x57,0x55); LIS3DSH_WriteReg(0x59,0xFC); LIS3DSH_WriteReg(0x5A,0xFC); LIS3DSH_WriteReg(0x40,0x05); LIS3DSH_WriteReg(0x41,0x11); LIS3DSH_WriteReg(0x42,0x00); LIS3DSH_Wri

Posted on March 07, 2016 at 01:04Hey. I understand that this topic is not the place, there was no forum for the addition.Help with data conversion, we need the full formula. For example, at current consumption register REG_CURRENT is 65527, as I understand it is a negative value, but in the calculation goes completely wrong values. #stc3105

Posted on March 03, 2016 at 18:02I am using the LIS2DH12 chip in a small battery powered box in users' vehicles. Whenever a user accelerates the vehicle, I would like to find out if the vehicle is moving forwards, or backwards, or turning, or going down the slope. However, one cannot guarantee how the user will orient this box in the vehicle. It could be upside down, tilted. Finding exact movement (forwards, backwards), is difficult without knowing the orientation of the box.I want to know if by using the 6D/4D orientation feature in the LIS2DH12 chip, if one can find the position of the box. The manual is light on the exact way to use this feature.From various sources that I searched online, it seems like one cannot deduce the exact orientation of the box(upside down, tilted etc.) without having an additional sensor like gyroscope. I wanted to verify from reliable sources if it is indeed not possib