EKF data rate

[honghongzhenbang]

I am currently attempting to use alternative hardware as the master board and re-implement the master board program. I have discovered that the raw data from the IMU is at a rate of 1000Hz, and the EKF is at a rate of 500Hz. However, in the master board program, it seems that the data is being sent to the PC end at a frequency of 1000Hz. This means that only 500 of the sent data points are unique and valid, while the other 500 points are duplicates. I am unsure if my understanding is correct.

[honghongzhenbang]

Another question, I have difficulty finding an IMU with a magnetometer, is the project's requirement for heading accuracy high?