/**
* Read the pressure and temperature.
* This method use the second order temperature
* compensation algorithm described in the datasheet.
* @param pressure Pressure pointer. hPa
* @param temperature Temperature pointer. ºC
* @param osr Oversample rate. Optional.
* @return Status of operation (true = success)
*/
bool MS561101BA::readValues(
float * pressure,
float * temperature,
int8_t osr) {
// Read the sensors
int32_t d1 = readD1(osr);
int32_t d2 = readD2(osr);
// Check for errors
if (d1 < 0 || d2 < 0) return false;
int32_t dT = d2 - (((uint32_t) getTREF()) << 8);
double t = 2000.0 + ((int64_t) dT) * getTEMPSENS() / POW_2_23;
int64_t off = (((int64_t) getOFFT1()) << 16) +
((int64_t) dT) * getTCO() / POW_2_7;
int64_t sens = (((int64_t) getSENST1()) << 15) +
((int64_t) dT) * getTCS() / POW_2_8;
// Second order temperature compensation
if (t < 2000) {
double square = pow (dT,2);
double t2 = square / POW_2_31;
square = pow (t-2000,2);
double off2 = square * 5 / 2;
double sens2 = square * 5 / 4;
if (t < 15) {
square = pow(t+1500,2);
off2 += square * 7;
sens2 += square * 11 / 2;
}
t -= t2;
off -= off2;
sens -= sens2;
}
double p = ((sens * d1 / POW_2_21) - off) / POW_2_15;
*temperature = float(t/100);
*pressure = float(p/100);
return true;
}
bool MS561101BA::TemperatureCompensation(int32_t * pressure, int32_t * temperature, int32_t d1, int32_t d2)
{
if (d1 < 0 || d2 < 0) return false;
int32_t dT = d2 - (((uint32_t) getTREF()) << 8);
double t = 2000.0 + ((int64_t) dT) * getTEMPSENS() / POW_2_23;
double off = (((int64_t) getOFFT1()) << 16) +
((int64_t) dT) * getTCO() / POW_2_7;
double sens = (((int64_t) getSENST1()) << 15) +
((int64_t) dT) * getTCS() / POW_2_8;
// Second order temperature compensation
if (t < 2000)
{
double square = pow (dT,2);
double t2 = square / POW_2_31;
square = pow (t-2000,2);
double off2 = square * 5 / 2;
double sens2 = square * 5 / 4;
if (t < 15)
{
square = pow(t+1500,2);
off2 += square * 7;
sens2 += square * 11 / 2;
}
t -= t2;
off -= off2;
sens -= sens2;
}
double p = ((sens * d1 / POW_2_21) - off) / POW_2_15;
*pressure = (int32_t) p;
*temperature = (int32_t) t;
return true;
}
