MS5611.cpp

/*

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  may be used to endorse or promote products derived from this software
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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
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*/

// MS5611 MOD-1009 barometric pressure and temperature sensor Arduino library
// Written originally by Embedded Adventures

#include "MS5611.h"
#include "Wire.h"



void MS5611Class::init() {
	Wire.beginTransmission(MS5611_ADDR);
	Wire.write(CMD_RESET);
	Wire.endTransmission();
}
	
uns16* MS5611Class::readCoefficients() {
	uns8 high_byte, low_byte;
	uns8 calib_addr;
	delay(5);
	for (int i = 0; i < 7; i++)
	{
		calib_addr = 0xA0 + (i * 2);
		Wire.beginTransmission(MS5611_ADDR);
		Wire.write(calib_addr);
		Wire.endTransmission();

		Wire.requestFrom(MS5611_ADDR, 2);
		if (Wire.available()) {
			high_byte = Wire.read();
			low_byte = Wire.read();
		}
		else {
			Serial.println("Data unavailable...");
		}

		C[i] = (high_byte << 8) | low_byte;
	}
	return C;
}

uns32 MS5611Class::readADC(uns8 code) {
	uns8 raw[3];

	Wire.beginTransmission(MS5611_ADDR);
	Wire.write(code);
	Wire.endTransmission();
	delay(10);
	Wire.beginTransmission(MS5611_ADDR);
	Wire.write(READ_ADC);
	Wire.endTransmission();

	Wire.requestFrom(MS5611_ADDR, 3);
	if (Wire.available()) {
		raw[2] = Wire.read();
		raw[1] = Wire.read();
		raw[0] = Wire.read();
	}
	return raw[0] + (raw[1] * 256) + (raw[2] * 65536);
}

void MS5611Class::calculate() {
	snd32 dT = D2 - ((uns64)C[5] * 256);
	snd64 OFF = ((snd64)C[2] * 65536) + ((C[4] * dT) / 128);
	snd64 SENS = ((snd32)C[1] * 32768) + ((C[3] * dT) / 256);
	TEMP = 2000 + (((snd64)dT * (snd64)C[6]) / 8388608);
	P = ((((snd64)D1 * SENS) / 2097152) - OFF) / 32768;
}

void MS5611Class::readMeasurements() {
	D1 = readADC(READ_MBAR);
	D2 = readADC(READ_TEMP);
	calculate();
}

double MS5611Class::getTemperature() {
	return TEMP / 100.0;
}

double MS5611Class::getPressure() {
	return P / 100.0;
}

MS5611Class ms5611;