User Manual

MPU-9250 Register Map and Descriptions
Document Number: RM-MPU-9250A-00
Revision: 1.4
Release Date: 9/9/2013
These registers are used to remove DC bias from the gyro sensor data output for X, Y and Z axes.
The values in these registers are subtracted from the gyro sensor values before going into the
sensor registers. Please refer to registers 67 to 72 for units.
4.4 Register 25 – Sample Rate Divider
Serial IF: R/W
Reset value: 0x00
BIT
NAME
FUNCTION
[7:0]
SMPLRT_DIV[7:0]
Divides the internal sample rate (see register CONFIG) to generate the
sample rate that controls sensor data output rate, FIFO sample rate.
NOTE: This register is only effective when Fchoice = 2’b11 (fchoice_b
register bits are 2’b00), and (0 < dlpf_cfg < 7), such that the average filter’s
output is selected (see chart below).
This is the update rate of sensor register.
SAMPLE_RATE=
Internal_Sample_Rate / (1 + SMPLRT_DIV)
Data should be sampled at or above sample rate; SMPLRT_DIV is only used for1kHz internal sampling.
4.5 Register 26 – Configuration
BIT
NAME
FUNCTION
[7]
-
Reserved
[6]
FIFO_MODE
When set to ‘1’, when the fifo is full, additional writes will not be written to fifo.
When set to ‘0’, when the fifo is full, additional writes will be written to the fifo,
replacing the oldest data.
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