void AKM8973_2_6_29::calibrate_magnetometer_analog_helper(float val, int i)
{
const float ANALOG_MAX = 126.0f;
const float BOUND_MAX = 240.0f;
/* The rate of forgetting encountering the minimum or maximum bound.
* Keeping this fairly large to make it less likely that analog gain
* gets adjusted by mistake. */
const float CALIBRATE_DECAY = 0.1f;
/* Autoadjust analog parameters */
if (val > ANALOG_MAX || val < -ANALOG_MAX) {
analog_offset[i] += val > ANALOG_MAX ? -1 : 1;
LOGI("Adjusting magnetometer axis %d to %d because of value %f", i, analog_offset[i], val);
calibrate_analog_apply();
/* The other axes are OK */
rc_min[i] = 0;
rc_max[i] = 0;
return;
}
/* If recorded digital bounds get close to completely used,
* we risk having to constantly adjust the analog gain. We
* should be able to detect this happening as user rotates the
* device. */
if (rc_max[i] - rc_min[i] > BOUND_MAX && fixed_magnetometer_gain > 0) {
fixed_magnetometer_gain -= 1;
LOGI("Adjusting magnetometer gain to %d", fixed_magnetometer_gain);
calibrate_analog_apply();
/* Bounds will change on all axes. */
for (int j = 0; j < 3; j ++) {
rc_min[j] = 0;
rc_max[j] = 0;
}
return;
}
rc_min[i] += CALIBRATE_DECAY;
rc_max[i] -= CALIBRATE_DECAY;
/* minimum value seen */
if (rc_min[i] > val) {
rc_min[i] = val;
}
/* maximum value seen */
if (rc_max[i] < val) {
rc_max[i] = val;
}
}
AKM8973_2_6_29::AKM8973_2_6_29(int gain)
: index(0), fixed_magnetometer_gain(15), magnetometer(600)
{
mbuf[0] = mbuf[1] = Vector();
magnetometer_gain = gain;
fd = open("/dev/akm8973_daemon", O_RDONLY);
SUCCEED(fd != -1);
SUCCEED(ioctl(fd, ECS_IOCTL_RESET, NULL) == 0);
calibrate_analog_apply();
}
AK8973B::AK8973B(int dgain, int again)
: magnetometer(600)
{
mbuf = Vector();
magnetometer_gain = dgain;
fixed_magnetometer_gain = again;
//starting offset
analog_offset[0]=-3;
analog_offset[1]=-3;
analog_offset[2]=-5;
fd = open("/dev/akm8973_daemon", O_RDONLY);
SUCCEED(fd != -1);
SUCCEED(ioctl(fd, ECS_IOCTL_RESET, NULL) == 0);
calibrate_analog_apply();
}
