TMP275.cpp

/*
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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
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*/

// TMP275 MOD-1001 RTC and Temperature Sensor Arduino library
// Written originally by Embedded Adventures

#include "TMP275.h"
#include "Wire.h"

static int measurementDelay;	//28ms, 55ms, 110ms, 220ms

void TMP275Class::init() {
	//Serial.println("init start");
	measurementDelay = 28;
	Wire.beginTransmission(TMP275_ADDR);
	Wire.write(CONF_REG);
	Wire.write(0x00);
	Wire.endTransmission();
	//Serial.println("init end");
}

uns8 TMP275Class::readConfigRegister() {
	uns8 config;
	Wire.beginTransmission(TMP275_ADDR);
	Wire.write(CONF_REG);
	Wire.endTransmission();
	
	Wire.requestFrom(TMP275_ADDR, 1);
	if (Wire.available())
		config = Wire.read();
	return config;
}

void TMP275Class::writeConfigRegister(uns8 config) {
	Wire.beginTransmission(TMP275_ADDR);
	Wire.write(CONF_REG);
	Wire.write(config);
	Wire.endTransmission();
}

float TMP275Class::getTemperature() {
	uns8 hi, lo;
	Wire.beginTransmission(TMP275_ADDR);
	Wire.write(TEMP_REG);
	Wire.endTransmission();
	
	delay(measurementDelay);
	
	Wire.requestFrom(TMP275_ADDR, 2);
	if (Wire.available()) {
		hi = Wire.read();
		lo = Wire.read(); 
	}
	sn16 temp = ((hi << 4) | (lo >> 4));
	return float(temp/16.0);
}

void TMP275Class::setResolution(int res) {
	uns8 config = readConfigRegister() & 0x9F;	//Mask out the res bits
	config |= uns8(res-1) << 5;
	
	writeConfigRegister(config);
	//Change measurement delay
	if (res == 1)
		measurementDelay = 28;
	else if (res == 2)
		measurementDelay = 55;
	else if (res == 3)
		measurementDelay = 110;
	else
		measurementDelay = 220;
}

void TMP275Class::enableShutdownMode(bool enable) {
	uns8 config = readConfigRegister();
	config &= 0xFE;		//Mask out LSB
	if (enable)
		config |= 0x01;
	writeConfigRegister(config);
}

void TMP275Class::enableOS() {
	enableShutdownMode(false);
	delay(measurementDelay);
	enableShutdownMode(true);
}

void TMP275Class::enableComparatorMode() {
	uns8 config = readConfigRegister();
	config &= 0xFD;	
	writeConfigRegister(config);
}

void TMP275Class::setHighTempThreshold(sn16 threshold) {
	Wire.beginTransmission(TMP275_ADDR);
	Wire.write(THIGH_REG);
	Wire.write(threshold >> 8);
	Wire.write(threshold & 0xFF);
	Wire.endTransmission();
}

void TMP275Class::setLowTempThreshold(sn16 threshold) {
	Wire.beginTransmission(TMP275_ADDR);
	Wire.write(TLOW_REG);
	Wire.write(threshold >> 8);
	Wire.write(threshold & 0xFF);
	Wire.endTransmission();
}

float TMP275Class::getHighTempThreshold() {
	uns8 hi, lo;
	Wire.beginTransmission(TMP275_ADDR);
	Wire.write(THIGH_REG);
	Wire.endTransmission();
	
	delay(measurementDelay);
	
	Wire.requestFrom(TMP275_ADDR, 2);
	if (Wire.available()) {
		hi = Wire.read();
		lo = Wire.read(); 
	}
	sn16 temp = ((hi << 4) | (lo >> 4));
	return float(temp/16.0);
}

float TMP275Class::getLowTempThreshold() {
	uns8 hi, lo;
	Wire.beginTransmission(TMP275_ADDR);
	Wire.write(TLOW_REG);
	Wire.endTransmission();
	
	delay(measurementDelay);
	
	Wire.requestFrom(TMP275_ADDR, 2);
	if (Wire.available()) {
		hi = Wire.read();
		lo = Wire.read(); 
	}
	sn16 temp = ((hi << 4) | (lo >> 4));
	return float(temp/16.0);
}

int TMP275Class::getFaults() {
	uns8 config = readConfigRegister();
	config = (config >> 3) & 0x03;
	return config;
}

TMP275Class tmp275;