projet3_temperature/lib/MeasureUnit/MeasureUnit.cpp

#include "MeasureUnit.h"

MeasureUnit::MeasureUnit(uint8_t *analogInput, 
uint16_t thermistorCount, 
uint64_t precResistor, 
ThermistorSetting thermistorSetting, 
AdcSetting adcSetting) : _analogInput(analogInput), _thermistorCount(thermistorCount), _precResistor(precResistor), _thermistorSetting(thermistorSetting), _adcSetting(adcSetting), _globalOffset(0), _error(OK)
{
  //Allocation dynamique des différent tableaux
  _temperatures = (double*) calloc(_thermistorCount, sizeof(double));
  _rOffsetMap = (double*) calloc(_thermistorCount, sizeof(double));
  _resistanceMap = (double*) malloc(_thermistorCount * sizeof(double));

  if(_temperatures == NULL || _rOffsetMap == NULL || _resistanceMap == NULL)
  {
    _error = MALLOC_ERR;
    _temperatures != NULL ? free(_temperatures):(void)_temperatures;
    _rOffsetMap != NULL ? free(_rOffsetMap):(void)_rOffsetMap;
    _resistanceMap != NULL ? free(_resistanceMap):(void)_resistanceMap;

    _temperatures = NULL;
    _rOffsetMap = NULL;
    _resistanceMap = NULL;
  }
}

MeasureUnit::~MeasureUnit()
{
  if(_error != MALLOC_ERR)
  {
    free(_temperatures);
    free(_rOffsetMap);
    free(_resistanceMap);
  }
}

/**
 * Methode permettant d'effectuer les mesures de température et de les récupérer
 */
double *MeasureUnit::getTemperatures()
{
  double courant(0), rPrecTension(0);
  //1) Nous calculons le courant présent dans la branche grace à la résistance de précision
  #ifdef DEBUG
  Serial.println("-------------");
  #endif
  
  for(int i(0); i < /*_adcSetting.getMeasureIteration()*/2500; i++)
  {
    delay(/*_adcSetting.getDelayBetweenIteration()*/2);
    
    unsigned int sample = analogRead(_analogInput[0]);
    rPrecTension += sample;
    
    #ifdef DEBUG
    Serial.print("Adc value : ");Serial.println(sample);
    #endif
  }
  
  #ifdef DEBUG
  Serial.println("-------------");
  #endif

  rPrecTension /= 2500;//_adcSetting.getMeasureIteration();
  #ifdef DEBUG
  Serial.print("Adc value average : ");Serial.println(rPrecTension);
  #endif
  rPrecTension *= _adcSetting.getQuantum();
  #ifdef DEBUG
  char buffer[10] = "";
  sprintf(buffer,"%.8f", rPrecTension);
  Serial.print("R prec voltage : ");Serial.println(buffer);
  #endif
  courant = rPrecTension / (double) _precResistor;
  //#ifdef DEBUG
  char buffer[10] = "";
  sprintf(buffer,"%.8f", courant);
  Serial.print("R prec current : ");Serial.println(buffer);
  //#endif
  
  
  //2) Nous calculons le delta de tensions pour chaque thermistances
  for(int i(1); i < _thermistorCount; i++)
  {
    _resistanceMap[i-1] = 0;
    
    for(int j(0); j < _adcSetting.getMeasureIteration(); j++)
    {
      delay(_adcSetting.getDelayBetweenIteration());
      
      int sample = analogRead(_analogInput[i]);
      
      _resistanceMap[i-1] += sample;
    }
    
    _resistanceMap[i-1] /= _adcSetting.getMeasureIteration();
    
    _resistanceMap[i-1] *= _adcSetting.getQuantum();
    
    /*if(i == 1)
      _resistanceMap[i-1] -= rPrecTension;
    else
      _resistanceMap[i-1] -= _resistanceMap[i-2];*/

    /*#ifdef DEBUG
    Serial.print("Debug voltage delta : ");Serial.println(_resistanceMap[i-1]);
    #endif*/
  }
  _resistanceMap[7] = _adcSetting.getVref();
  
  for(int i(_thermistorCount-1); i > 0; i--)
  {
    #ifdef DEBUG
    Serial.print("Debug voltage level ");Serial.print(i);Serial.print(" : ");Serial.println(_resistanceMap[i]);
    #endif
    //Calcule de delta :
    _resistanceMap[i] -= _resistanceMap[i-1];
    #ifdef DEBUG
    Serial.print("Debug voltage delta : ");Serial.println(_resistanceMap[i]);
    #endif
  }
  
  for(int i(0); i < _thermistorCount; i++)
  {
    //3) Nous en déduisons la résistance
    _resistanceMap[i] /= courant;
    //4) Nous en déduisons la temperature
    _temperatures[i] = computeTemperature(_thermistorSetting.getBeta(), _resistanceMap[i], _thermistorSetting.getRat25());
    _temperatures[i] += _rOffsetMap[i] + _globalOffset;
    #ifdef DEBUG_TEMP
    Serial.print("Temperature ");Serial.print(i);Serial.print(" : ");Serial.println(_temperatures[i]);
    #endif
  }
  
  return _temperatures;
}

double MeasureUnit::computeTemperature(double beta, double resistance, double rAt25)
{
  return (((25.0+273.15) * beta) / (beta + (25.0+273.15)*log(resistance / rAt25))) - 273.15;
}

void MeasureUnit::setGlobalTempOffset(double offset)
{
  _globalOffset = offset;
}

double MeasureUnit::getGlobalTempOffset()
{
  return _globalOffset;
}

/**
 * Cette méthode permet de calibrer toutes les temperatures en faisans la moyenne et appliquant un offset individuel
 */
void MeasureUnit::levelTemperaturesOff()
{
  double averageTemp(0);

  for(int i(0); i < _thermistorCount; i++)
  {
    averageTemp += _temperatures[i];
  }

  averageTemp /= _thermistorCount;

  for(int i(0); i < _thermistorCount; i++)
  {
    _rOffsetMap[i] = averageTemp - _temperatures[i];
  }
  
}

double *MeasureUnit::getROffsetMap()
{
  return _rOffsetMap;
}