LM35.cpp

00001 #include "LM35.h"
00002 
00003 LM35Therm::LM35Therm(PinName analogPin, float compensation) {
00004     _pAin = new AnalogIn(analogPin);
00005     _calibrate = compensation;
00006     _isFirstRead = true;
00007 }
00008 
00009 LM35Therm::~LM35Therm() {
00010     delete _pAin;
00011 }
00012 
00013 void LM35Therm::getAverageValue() {
00014     _sumAnalog = 0;
00015     
00016     for (uint8_t i = 0; i < SAMPLE_COUNT; i++) {
00017         analogSamples[i] = _pAin->read();
00018     }  
00019     
00020     for (uint8_t i = 0; i < SAMPLE_COUNT; i++) {
00021         _sumAnalog = _sumAnalog + analogSamples[i];   
00022     }  
00023     
00024     averageAnalog = _sumAnalog / SAMPLE_COUNT;
00025     _sumAnalog = 0;
00026     
00027     if (_isFirstRead) {
00028         for (uint8_t i = 0; i < SAMPLE_COUNT; i++) {
00029             analogAverageSamples[i] = averageAnalog;
00030             _sumAnalog = _sumAnalog + analogAverageSamples[i];
00031         }        
00032         filtedAvgAnalog = _sumAnalog / SAMPLE_COUNT;
00033         _isFirstRead = false;    
00034     }
00035     else {
00036         for (uint8_t i = 0; i < SAMPLE_COUNT - 1; i++) {
00037             analogAverageSamples[i] = analogAverageSamples[i];
00038             _sumAnalog = _sumAnalog + analogAverageSamples[i];
00039         }       
00040         analogAverageSamples[SAMPLE_COUNT - 1] = averageAnalog;      
00041         _sumAnalog = _sumAnalog + analogAverageSamples[SAMPLE_COUNT - 1];
00042     }
00043     filtedAvgAnalog = _sumAnalog / SAMPLE_COUNT;
00044 }
00045 
00046 void LM35Therm::setCompensation(float newCompensation) {
00047     _calibrate = newCompensation;
00048 }
00049 
00050 float LM35Therm::LM35Therm::getTempInC() {
00051     _readVoltage  = filtedAvgAnalog * 3.3;
00052     float avgVolt = filtedAvgAnalog * _calibrate * 1000.0;
00053     tempInC       = avgVolt;
00054     return tempInC;
00055 }
00056 
00057 float LM35Therm::LM35Therm::getTempInF() {
00058     tempInF = (9.0 * tempInC)/5.0 + 32.0;
00059     return tempInF;
00060 }