MEMS and sensors

Posted on July 29, 2015 at 17:05All:I have procurred a STEVAL-MKI109V2 and plug-in board STEVAL-MKI142V1 (LPS25H). When I bring up the UNICO ''Cross-platform User Interface for MEMS demonstration kits'', I am able to see that the device is operating, and it has good values. However, can the interface be changed from the default SPI to run as I2C?I would like to do this to evaluate a target board that has been made up with an I2C interface.I realize that I2C may not be an option for the demo, but is it an option?If so, how do I change the UNICO settings to use the I2C option?Regards,Todd Anderson #unico

Posted on July 31, 2015 at 02:16Hey I'm trying a new board, this is the stm32f411e-disco and I can't read acc. values, they are always 0x00 I've generated the project with STM32CubeMX V4.9.0 The config and the main code are below: &sharpinclude ''stm32f4xx_hal.h'' I2C_HandleTypeDef hi2c1; HAL_StatusTypeDef acc_ready, acc_read; uint8_t readXYZ[6]; void SystemClock_Config(void); static void MX_GPIO_Init(void); static void MX_I2C1_Init(void); int main(void) {   HAL_Init();

Posted on July 20, 2015 at 13:54Hi,We are developing a new sensor device where we are using the HTS221 sensor currently, the project is now in prototyping phase. Last week the HRS221 status was set to NRND on st.com, but this week the status is back to Active again. Mouser still lists the product as NRND this week though. So of course we are worried that we are designing the product with a sensor that is about to be discontinued, can we please have an official statement on the longer term (~2 years) plans for HTS221?

Posted on July 29, 2015 at 20:12I'm trying to talk to a LSM6D3 over PCI. Everything's connected according to the datasheet in mode 1 (3.3v to VDD and VDDIO, SCx and SDx tied to GND) . I'm starting slow, so here's clock (SPC) and chip select (CS):https://drive.google.com/file/d/0B979a_DgADKmUFNhOGtFdXR0bDg/view?sp=sharingHere's clock and MOSI (SDI/SDA):https://drive.google.com/file/d/0B979a_DgADKmVkl2SlpSOXRPTWs/view?usp=sharingAs you can see, the clock polarity and phase are good, the bits on the rising edge of clock are clearly 10001111, or 0x8F, which indicate a read of register 0x0F (''WHO_A

Posted on April 09, 2015 at 01:12Since power cycle is not an option for my application, I'm curious if there's a way to do a soft system reset ('reboot') to the lsm9ds1 module? #lsm9ds0

Posted on August 24, 2014 at 10:44Hi, I'm trying to understand the readings I got for a LSM9DS0 on my board. If I hold the board on my desk, according to the datasheet I should read a negative value for the Z-AXIS, because Z-AXIS vector points up,  instead I read a positive 1g value. The same happens with the other two axes. Are all the readings inverted? Or am I wrong with something?

Posted on June 16, 2015 at 08:38Hi, I use LPS25H in my project. Based on the application note AN4450 page 13,(example 1) when I configure the LPS25H to the mode that ODR is 25 Hz,  pressure average 512, temperature average 64 (register 0x20 is 0xC0, register 0x10 is 0x0F), the current is 690uA. This value is similar to the result in the application note.  However,(example 2)In the application note, the current is 26.4uA when ODR is 1 Hz, pressure average 512, temperature average 64. However, on my board, when I configure the LPS25H into the same mode (register 0x20 is 0x90, register 0x10 is 0x0F), the current is about 390uA. Why?

Posted on July 23, 2015 at 11:57Hi,I'm using LIS3MDL for a while now and I recently encountered a problem on the sensors detected via the self test option.Some of the sensors I'm using began to give me some strange data. As far as I understand the problem I think that the X and Y axis are swapped and in some occasions, they can be inverted too.I tried different initializations as well as a memory REBOOT (from CTRL_REG2) of the sensor with the same result.Can someone tell me how I can reset the sensor to have them work properly again? Can the calibration settings be affected during the sensor lifespan? Can they be reset?Is there a specific command to swap the axis that I did unintentionally? #calibration #lis3mdl #swap-axis

Posted on June 13, 2014 at 04:14use MCU SPI MODEL , I have used oscillometer test.write @0x20=0x00read  @0x20=0x1ewrite @0x20=0x84read  @0x20=0x1eerror... 

Posted on July 20, 2015 at 18:26Although this is an old post, thought I'd chime in here in case it's useful for anyone else going forward. The LSM330D accelerometer symbol/footprint is available for download here -- just select Altium as the download option: http://www.snapeda.com/parts/LSM330D/STMicroelectronics/view-part/

Posted on July 20, 2015 at 17:40Hello, the VL6180X Sensor is in continuous mode, I am polling Interrupt_status_gpio. Sometimes the Laser switch off and the Interrupt_status_gpio is always 0x00. Vcc is 2,8V. Whats the problem?

Posted on July 13, 2015 at 19:57Hello, I am working with the STEVAL-MKI153V1  eval board and have configured interrupt 1 to be the ''data ready'' interrupt. My question is how do I calculate the interrupt duration? All the data sheet says is it is calculated based on the ODR.   Regards, Emach #h3lis331dl

Posted on July 10, 2015 at 17:34 LSM303DLHC Data Sheet says The LSM303DLHC features two data-ready signals (RDY) which indicate when a new set of measured acceleration data and magnetic data are available but Figure 4 only shows one DRDY pin out, does that mean that when the pin is set, both accelerometer and compass has new data, or do I have to check status/ctrl registers to see if accelerometer or magnetometer has data? #lsm303dlhc #drdy

Posted on July 08, 2015 at 21:37On the data sheet it is recommended to add 3 capacitors to the system. '' The device core is supplied through the Vdd line while the I/O pads are supplied through the Vdd_IO line. Power supply decoupling capacitors (100 nF ceramic, 10 μF aluminum) should be placed as near as possible to pin 9 of the device (common design practice). All the voltage and ground supplies must be present at the same time to have proper behavior of the IC (refer to Figure 5). It is possible to remove Vdd while maintaining Vdd_IO without blocking the communication bus, in this condition the measurement chain is powered off. The functionality of the device and the measured acceleration data is selectable and accessible through the I2C or SPI interfaces. When using the I2C, CS must be tied high. The functions, the threshold and the timing of the two interrupt pins (INT

Posted on July 08, 2015 at 14:00Hello, does anybody know how accurate the data rate of the LIS331HH sensors should be? I use two with a data rate of 1000Hz of them and want to synchronize the measurment results. For this reason i measured the Interrupt Pin INT1 of both sensors. The first one has a data rate of 995Hz and the second one has a data rate of 1000Hz. Is there a tolerance value for the data rate of these sensores? Best regards, max

Posted on July 06, 2015 at 14:49I am using Lsm9ds0 device connected to imx6 processor via i2c with following configuration. Set Gyro ORD to 95hz. Set Watermark level to 30 Set to Stream mode register configuration {CTRL_REG3_G, 0x04},     {CTRL_REG4_G, 0x20},     {CTRL_REG5_G, 0x40},     {CTRL_REG1_G, 0x0F},     {FIFO_CTRL_REG_G, 0x5E}, I would expect a water mark interrupt at an interval of every 316ms(1/95*30). but I could see interrupt at an interval of every 340ms Could you please help me to identify the delay in interrupt. The same behavior is observed in the case of accelerometer and magnetometer. Inside ISR the entire FIFO data is read in burst mode based on the FIFO status register. #lsm9ds0

Posted on July 06, 2015 at 09:06Hello,I am using Lsm303D, it works well but I am not lucky with the interrupt functions.Anybody helps me to give me a good sequence of sets to have an interrupt on INT1 or INT2 when my board is slightly shaken ?I have programmed registers as below:Reg. 0x30 = 0xBF;Reg. 0x12 = 0x04;Reg. 0x20 = 0x47;Reg. 0x22 = 0xFF;Reg. 0x32 = 0x02;Reg. 0x33 = 0xFF;Thanks for your help,Joseph #interrupt-lsm303d

Posted on July 02, 2015 at 14:53Hello there, I had placed the LIS2DH on my board , and it seems to work fine. using default setting and 10Hz sampling, when i am putting the PCBA on a fixed position, and X axis raw data is unstable from - 128 to 128. other axis seems to work fine - this is the raw data driven without any particular SW manipulation. can someone advise why?

Posted on July 02, 2015 at 14:50Hey, I have to communicate with LIS2DHH , and dummy byte received fine, however when i am trying to read axis data i get only 0.

Posted on December 17, 2013 at 16:12Hello,I bought a STEVAL-MKI109v1  evaluation board, and a STEVAL-MKI114v1 probe about 1,5 years ago.Yesterday I tried to get it to work with the latest version of the Unico test software, but the program would always hang as soon as I clicked on anything that would read data from the sensor. So I figured I needed to upgrade the firmware.In the Unico manual, it said that the Dfu firmware updater on the eval board needed upgrading first, before the firmware v3 properly said could be installed. So I uploaded the Dfu firmware that came with that latest version of Unico onto the evaluation board.In order to update the firmware, the device needs to be put in Dfu mode, by holding a button while powering it up, so I did that.However, the updater warned me that I could not back up the old firmware, nor verify whether the new firmware is correct, precisely because the device was in dfu

Posted on June 24, 2015 at 19:36Hello all, I would like to use an off-the-shell CVC as readout for my capacitive MEMS accelerometer. My concern is the acceptable input bulk capacitance, that is 30pF in my case. I have looked in a couple of CVCs, MS3110 and CVC1.1, but the former one input capacitance is 10pF and the latter one is 6.3pF. I would appreciate if you have any suggestion in this regard. Thank you very much, Bahareh #readout-circuit

Posted on April 19, 2015 at 20:33 Hi to all, I'm trying to use this demo, and I have noticed that my program remains blocked at this line of the iNEMO_AHRS_Init() void iNEMO_AHRS_Init(iNEMO_SENSORDATA* pSensorData, iNEMO_EULER_ANGLES* pAngle, iNEMO_QUAT* pQuat) { console_out(''ciao1_1''); /* Initialize all the EKF Matrix to Zero */ pMat_P = iNEMO_fMatCreateZero(7,7); console_out(''ciao1_2''); pMat_Fsys = iNEMO_fMatCreateUnit(7,7); console_out(''ciao1_3''); pMat_Q = iNEMO_fMatCreateZero(7,7); console_out(''ciao1_4''); pMat_Pnew = iNEMO_fMatCreateZero(7,7); Since the last call is like the previous, I think that maybe my heap is too small. It is a correct idea? In this case, how to increase it? Thank you #inemo-engine #heap #inemo

Posted on June 16, 2015 at 12:08Guys, I hope that I started this discussion in good time. I am a newbie in accelerometer application and currently on a very tight schedule to finish a pedometer application. Pardon me if my question sounds silly. Here is my situation: I am using state machines to fully keep track of the walking, jogging and running activity. Everything works well and accuracy is very good for the following step speed. At 120 steps per minute - accuracy is very good. It detected 197steps out of 200. SM2 is in walking_observing_running.   At 130 steps per minute - accuracy is very good. It detected 194steps out of 200. SM2 is in walking_observing_running. At 180 steps per minute - accuracy is very good. It detected 192steps out of 200. SM2 is in running_observing_walking. Now, the inaccuracy occurs when I tested at 140 st

Posted on August 16, 2014 at 06:03Hi,I am Jessenow,i will use MP45DT02 in my projectbut i evaluated it in STM32F407-DISCOVERY,i found a kind of terrible noise , it sounds like ''dot……dot……dot……''，especially female voice.wish a solutionthank you very much

Posted on June 09, 2015 at 15:36Hi,I am using LIS3DSH accelerometer, sampling rate 100HZ scale = +-2G. What I see is from time to time is noise what is coming from one of the axis, I tried to add more decoupling caps, thy to change internal filter settings nothing helps.Please see attached for your reference.Thank you for the help.Regards,Andrew