ASM330LHH TDA bit not set to 1?

[ggob]

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?

[ggob]

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?

[ggob]

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.

[Federica Bossi · Accepted solution]

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.