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Visitor II
September 1, 2025
Solved

ASM330LHH TDA bit not set to 1?

  • September 1, 2025
  • 2 replies
  • 566 views

If the TDA bit is not set to “1” even once after 400ms has passed after the sensor is turned on, is it likely that the startup has failed?

    This topic has been closed for replies.
    Best answer by Federica Bossi

    Hi @ggob ,

    The TDA bit (Temperature Data Available) is set to 1 when new temperature data is ready to be read.

    TDA is set to 1 every time new temperature data is available, which depends on the temperature sensor ODR. The temperature sensor ODR is typically tied to or configurable independently from the gyro and accelerometer ODR. After enabling the gyro and accelerometer via CTRL1_XL and CTRL2_G, the temperature sensor starts sampling at its own ODR. The TDA bit will be set to 1 periodically, each time a new temperature sample is ready.

    The duration for which TDA remains set to 1 is very short, usually until the STATUS_REG is read or the temperature data register is read, after which the bit resets to 0 until the next new data is ready.

    2 replies

    ggobAuthor
    Visitor II
    September 2, 2025

    After turning on the gyro and accelerometer with the CTRL1_XL and CTRL2_G registers of the ASM330LHH, if the TDA bit in the STATUS_REG does not change to 1 (XLDA and GDA are set to 1), is it effective as a countermeasure to cause the TDA bit to change to 1to turn off the gyro and accelerometer with the CTRL1_XL and CTRL2_G registers and then turn on both sensors again?

    ggobAuthor
    Visitor II
    September 11, 2025

    I checked the TDA bit 3 seconds after enabling the gyro and accelerometer in the CTRL1_XL and CTRL2_G registers of the ASM330LHH and it was set to 1. 400 ms later it may not be set to 1. I would like to know the maximum time that the TDA bit is set to 1 after enabling the gyro and accelerometer.

    Technical Moderator
    September 11, 2025

    Hi @ggob ,

    The TDA bit (Temperature Data Available) is set to 1 when new temperature data is ready to be read.

    TDA is set to 1 every time new temperature data is available, which depends on the temperature sensor ODR. The temperature sensor ODR is typically tied to or configurable independently from the gyro and accelerometer ODR. After enabling the gyro and accelerometer via CTRL1_XL and CTRL2_G, the temperature sensor starts sampling at its own ODR. The TDA bit will be set to 1 periodically, each time a new temperature sample is ready.

    The duration for which TDA remains set to 1 is very short, usually until the STATUS_REG is read or the temperature data register is read, after which the bit resets to 0 until the next new data is ready.