LSM6DSV16X double tap interrupt stops triggering

[BEnge.1]

Hello,

I am using the LSM6DSOX IMU to detect a double tap. The IMU is connected to SPI1 of a STM32U5 and the INT1 pin is connected to a GPIO (PB2) of the STM32U5 configured as external interrupt.

Sometimes the double tap detection works correctly but suddently the INT1 pin is not triggered anymore even though a double tap is performed.

At the same time I am also sampling the acceleration from the IMU via SPI and I can see that this still works. Meaning that the IMU is still working. 

I also have a SD card connected on SDMMC1 and I notice that when I write data on the SD card periodically, at some point the INT1 pin stops triggering. When I don't write any data, the INT1 pin works as intended.

Do you have any idea why the INT1 pin is not triggered anymore? I checked the level of the INT1 pin with a logic analyser and I see that it stays low, meaning that the issue comes from the IMU and not the STM32U5. However, I can confidently say that the INT1 pin not triggering is linked to writing data to the FATFS sd card connected on SDMMC1. That does not make any sense to me.

The pins used are:

For the IMU:

- INT1: PB2

- MOSI: PA7

- MISO: PA6

- CLK: PA5

For the SDMMC1:

- SD_DAT0: PC8

- SD_DAT1: PC9

- SD_DAT2: PC10

- SD_DAT3: PC11

- SD_CLK: PC12

- SD_CMD: PC2

- SD_CI: PB9

Thanks,

Benjamin

[Federica Bossi]

Hi @BEnge.1 ,

Have you already tried to follow our official example on Github?

Let me know if this helps!

[BEnge.1]

Hi @Federica Bossi, thanks for the reply. My code actually works well and I was able to setup the tap detection as I need it to be. However, my problem is that for a reason that I cannot understand, when I start writing on the SD card, the IMU stops triggering the INT pint whenever a double tap is performed. 

Would you have an idea of why this weird interaction happens ? 

Thanks,

Benjamin