lsm303d/l3gd20: change filters to 50Hz analog on-chip filters

after discussion with Leonard these analog on-chip filters should be
at 50Hz
This commit is contained in:
Andrew Tridgell 2013-12-04 22:54:02 +11:00 committed by Lorenz Meier
parent b0bb5a3450
commit 476070510e
2 changed files with 14 additions and 4 deletions

View File

@ -93,10 +93,15 @@ static const int ERROR = -1;
/* keep lowpass low to avoid noise issues */
#define RATE_95HZ_LP_25HZ ((0<<7) | (0<<6) | (0<<5) | (1<<4))
#define RATE_190HZ_LP_25HZ ((0<<7) | (1<<6) | (0<<5) | (1<<4))
#define RATE_190HZ_LP_50HZ ((0<<7) | (1<<6) | (1<<5) | (0<<4))
#define RATE_190HZ_LP_70HZ ((0<<7) | (1<<6) | (1<<5) | (1<<4))
#define RATE_380HZ_LP_20HZ ((1<<7) | (0<<6) | (1<<5) | (0<<4))
#define RATE_380HZ_LP_25HZ ((1<<7) | (0<<6) | (0<<5) | (1<<4))
#define RATE_380HZ_LP_50HZ ((1<<7) | (0<<6) | (1<<5) | (0<<4))
#define RATE_380HZ_LP_100HZ ((1<<7) | (0<<6) | (1<<5) | (1<<4))
#define RATE_760HZ_LP_30HZ ((1<<7) | (1<<6) | (0<<5) | (0<<4))
#define RATE_760HZ_LP_35HZ ((1<<7) | (1<<6) | (0<<5) | (1<<4))
#define RATE_760HZ_LP_50HZ ((1<<7) | (1<<6) | (1<<5) | (0<<4))
#define RATE_760HZ_LP_100HZ ((1<<7) | (1<<6) | (1<<5) | (1<<4))
#define ADDR_CTRL_REG2 0x21
@ -662,15 +667,15 @@ L3GD20::set_samplerate(unsigned frequency)
} else if (frequency <= 200) {
_current_rate = 190;
bits |= RATE_190HZ_LP_70HZ;
bits |= RATE_190HZ_LP_50HZ;
} else if (frequency <= 400) {
_current_rate = 380;
bits |= RATE_380HZ_LP_100HZ;
bits |= RATE_380HZ_LP_50HZ;
} else if (frequency <= 800) {
_current_rate = 760;
bits |= RATE_760HZ_LP_100HZ;
bits |= RATE_760HZ_LP_50HZ;
} else {
return -EINVAL;
}

View File

@ -599,7 +599,12 @@ LSM303D::reset()
accel_set_range(LSM303D_ACCEL_DEFAULT_RANGE_G);
accel_set_samplerate(LSM303D_ACCEL_DEFAULT_RATE);
accel_set_driver_lowpass_filter((float)LSM303D_ACCEL_DEFAULT_RATE, (float)LSM303D_ACCEL_DEFAULT_DRIVER_FILTER_FREQ);
accel_set_onchip_lowpass_filter_bandwidth(0); // this gives 773Hz
// we setup the anti-alias on-chip filter as 50Hz. We believe
// this operates in the analog domain, and is critical for
// anti-aliasing. The 2 pole software filter is designed to
// operate in conjunction with this on-chip filter
accel_set_onchip_lowpass_filter_bandwidth(LSM303D_ACCEL_DEFAULT_ONCHIP_FILTER_FREQ);
mag_set_range(LSM303D_MAG_DEFAULT_RANGE_GA);
mag_set_samplerate(LSM303D_MAG_DEFAULT_RATE);