SW_RESET on lsm6dsv16x bit is never cleared

[sneakyHulk]

Dear Community,

I think I have encountered an uncommon problem. The SW_RESET bit in CTRL3 on the lsm6dsv16x does not change to 0 again. In https://www.st.com/resource/en/datasheet/lsm6dsv16x.pdf it states that after the software reset this bit is automatically cleared. Even after disconnecting the power and doing a reboot, also of the chip itself this bit wont change back to 0. I use https://github.com/STMicroelectronics/lsm6dsv16x-pid to communicate with the chip, and other things like reading who_am_i and so on work normally. But otherwise, I only get meaningless readings from the sensor. What can be done about this, especially the reset bit?

Thanks and greetings

[Federica Bossi]

Hi @sneakyHulk ,

WHO_AM_I is read correctly, so basic I²C/SPI communication seems fine.
If the SW_RESET bit in CTRL3 never clears, the most likely causes are:

• Wrong or incomplete write to CTRL3 (0x12)
• Power or reset issue: for example, VDD/VDDIO not stable

What you could do:

1. Minimal sequence: read CTRL3, write 0x01 to 0x12, wait >10 ms, read CTRL3 again and log the raw values. Without using the driver.
2. Verify VDD and VDDIO levels and that the device is fully power‑cycled.
3. Use a logic analyzer to confirm that register 0x12 is really written and read with the expected bytes.

[sneakyHulk · Accepted solution]

Thanks Federica Bossi, I managed to fix the issue. The problem was caused by using a Repeated Start condition during I²C reads instead of sending a Stop condition followed by a new Start condition. Because of this, all read operations were returning inconsistent and implausible data. After correcting the I²C transaction sequence, everything is now working perfectly. Thanks again for the support! Greetings.