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Visitor II
November 25, 2020
Solved

Raw data from lsm6dsox

  • November 25, 2020
  • 3 replies
  • 1351 views

Hello,

In my test board, data from accelerometer and magnetometer are stable.

But gyro data has many spikes even though it is put in desk and not moving.

0693W000005CYLqQAO.pngDo you have any idea for what cause this and how to fix it?

lsm6dsox and lis3mdl are used for test.

    This topic has been closed for replies.
    Best answer by Eleon BORLINI

    Hi @Community member​ ,

    glad that you solved your issue!

    >> I guess that Power down and ODR OFF might be same. Is there a difference?

    Yes, you are right. ODR = 000bin and Power down are the same condition.

    For completeness, the gyroscope is capable of a mode intermediate between the low power and the power down, i.e. the Sleep mode. As explained in the app note AN5272, p.18 : "While the gyroscope is in Sleep mode the circuitry that drives the oscillation of the gyroscope mass is kept active. Compared to gyroscope Power-Down, turn-on time from Sleep mode to Low-Power/Normal/High-Performance mode is drastically reduced. If the gyroscope is not configured in Power-Down mode, it enters in Sleep mode when the Sleep mode enable (SLEEP_G) bit of CTRL4_C register is set to 1, regardless of the selected gyroscope ODR".

    -Eleon

    3 replies

    ST Employee
    November 25, 2020

    Hi @Community member​ ,

    which is, first, the unit of measure of the Gyroscope (on the graph y axis)? And which is the Gyro configuration (Mode, ODR, FS...)

    If the it were milli-dps, it's a good result, since the sensitivity is 4.375 mdsp/LSB for FS = 250dps, from the datasheet, p9.

    If it were dps, these could be a little high values considering that the typ ZRL is ±1dps. Are you sure you are not picking the table on which your device is, for any reason? The gyroscope is very sensible to little shocks, that may not be perceived by the human being.

    -Eleon

    JPARK.2Author
    Visitor II
    November 26, 2020

    Hi,

    Gyroscope Y axis means mdps.

    Gyro is configured like below 

    • LSM6DSOX_GY_ODR_1667Hz
    • LSM6DSOX_2000dps

    Time to time, Spikes get bigger(more than +-100mdps).

    In my SW, sleep mode is configured too.

    After replacing one function, problem is fixed.

    • Origin: during initialize, set act mode to LSM6DSOX_XL_12Hz5_GY_PD
    • New: before entering sleep mode, update ODR to LSM6DSOX_XL_ODR_12Hz5 and LSM6DSOX_GY_ODR_OFF

    I guess that Power down and ODR OFF might be same. Is there a difference?

    ST Employee
    November 26, 2020

    Hi @Community member​ ,

    glad that you solved your issue!

    >> I guess that Power down and ODR OFF might be same. Is there a difference?

    Yes, you are right. ODR = 000bin and Power down are the same condition.

    For completeness, the gyroscope is capable of a mode intermediate between the low power and the power down, i.e. the Sleep mode. As explained in the app note AN5272, p.18 : "While the gyroscope is in Sleep mode the circuitry that drives the oscillation of the gyroscope mass is kept active. Compared to gyroscope Power-Down, turn-on time from Sleep mode to Low-Power/Normal/High-Performance mode is drastically reduced. If the gyroscope is not configured in Power-Down mode, it enters in Sleep mode when the Sleep mode enable (SLEEP_G) bit of CTRL4_C register is set to 1, regardless of the selected gyroscope ODR".

    -Eleon