Imu_gyro_ratemax

where can this frequency tuned up more accurate all other controllers e.g. Pixracer (799.4Hz), Omnibus F4 (1000Hz), Pixfalcon (400Hz) return absolutely accurate values in nsh: sensors status.
with F777 it returns rates that are always 1% or 2% too low:
(it seems that this frequency is used as clock for OneShot pwm out as well)
INFO [vehicle_acceleration] selected sensor: 3670026 (0), rate: 1984.8 Hz
INFO [vehicle_acceleration] estimated bias: [0.0000 0.0000 0.0125]
INFO [sensor_calibration] ACC 3670026 EN: 1, offset: [0.0217 -0.0991 0.0972] scale: [0.9980 1.0006 0.9972]

INFO [vehicle_angular_velocity] selected sensor: 3670026 (0), rate: 1984.8 Hz
INFO [vehicle_angular_velocity] estimated bias: [-0.0013 0.0036 0.0011]
INFO [sensor_calibration] GYRO 3670026 EN: 1, offset: [0.0230 -0.0117 -0.0007]

board.h STM32_VCO_FREQUENCY = 218 can tune it to exact 2000 but changes all other rates too