Hello,
I would like to use the MPU9259 with the FIFO but without the low pass filter at a certain rate, namely slightly above 100Hz. However, the data sheet is confusing. According to this, I cannot configure the FIFO sample rate since:
This register is only effective when Fchoice = 2’b11 (fchoice_bThese values however imply that the low pass filter (at least for the gyroscope) must be enabled. I would like to avoid this. Is there a way?
register bits are 2’b00), and (0 < dlpf_cfg < 7), such that the average filter’s
output is selected (see chart below).
Also, in that same section, what is the internal sample rate (see register CONFIG). I should look at register CONFIG, but there's no information to be found.
To add insult to injury, there's this quote after the table at the desciption of the Accelerometer Config 2 register:
The data output rate of the DLPF filter block can be further reduced by a factor of 1/(1+SMPLRT_DIV), where SMPLRT_DIV is an 8-bit integer.Following is a small subset of ODRs that are configurable for the accelerometer in the normal modein this manner (Hz):
So setting SMPLRT_DIV to an appropiate value to have the FIFO sample at 100Hz makes the acccelerometer sample at a completely different rate? What about the gyro.. does it also change it's sample rate when setting some obscure register?
Please help me.