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PT100
Commit 093e6051 authored by João Lino's avatar João Lino
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PT100.cpp 0 → 100644
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/*
PT100.cpp - Library for measuring temperature with a PT100.
Created by João Lino, June 24, 2015.
Released into the public domain.
*/
#include "Arduino.h"
#include "PT100.h"
PT100::PT100(char *name,
int OutputPin_SensorPower,
int OutputPin_ThirdLinePower,
int InputPin_TemperatureReading,
int InputPin_ThirdLineReading,
int TimeBetweenReadings,
float ADCVmax,
float Vs,
float R1,
float R2,
float m,
float b) {
_name = name;
_OutputPin_SensorPower = OutputPin_SensorPower;
_OutputPin_ThirdLinePower = OutputPin_ThirdLinePower;
_InputPin_TemperatureReading = InputPin_TemperatureReading;
_InputPin_ThirdLineReading = InputPin_ThirdLineReading;
_TimeBetweenReadings = TimeBetweenReadings;
_ADCVmax = ADCVmax;
_Vs = Vs;
_R1 = R1;
_R2 = R2;
__m = m;
__b = b;
_temperatureAverage = 24.0;
_measuredTemperature = 24.0;
_lastTemperatureRead = 0;
_VoutAnalogSample = -1;
_VoutPreviousAnalogSample = -1.0;
_temperatureMeasurementsMarker = 0;
_rPT100MeasurementsMarker = 0;
_rLineMeasurementsMarker = 0;
_measuredTemperatureDeviation = 0.0;
_sampleDeviation = 0.0;
analogReference(INTERNAL1V1); // EXTERNAL && INTERNAL2V56 && INTERNAL1V1
pinMode(_OutputPin_SensorPower, OUTPUT); // setup temperature sensor input pin
pinMode(_OutputPin_ThirdLinePower, OUTPUT); // setup temperature sensor input pin
digitalWrite(_OutputPin_SensorPower, LOW); // initialize sensor on
digitalWrite(_OutputPin_ThirdLinePower, LOW); // initialize sensor on
}
void PT100::setPower(float ADCVmax, float Vs) {
_ADCVmax = ADCVmax;
_Vs = Vs;
}
void PT100::safeHardwarePowerOff() {
digitalWrite(_OutputPin_SensorPower, LOW); // Turn temperature sensor OFF for safety
digitalWrite(_OutputPin_ThirdLinePower, LOW); // Turn temperature sensor OFF for safety
}
void PT100::measure(boolean ln) {
if(millis() - _lastTemperatureRead >= _TimeBetweenReadings) { //time to measure temperature
/** measure Vout analog sample */
_VoutPreviousAnalogSample = _VoutAnalogSample; // Store previous
//digitalWrite(_OutputPin_SensorPower, HIGH); // Turn on sensor
//delay(10);
_VoutAnalogSample = analogRead(_InputPin_TemperatureReading); // Get a reading
//float test = analogRead(A7);
//digitalWrite(_OutputPin_SensorPower, LOW); // Turn off sensor
_lastTemperatureRead = millis(); // Mark time of temperature reading
/** Calculate temperature value */
float Vout = (_VoutAnalogSample + _VoutPreviousAnalogSample) / 2 * _ADCVmax / CONSTANT_ADC_STEP_COUNT;
//float Rtest = 608 / ( _Vs / (test * _ADCVmax / CONSTANT_ADC_STEP_COUNT) - 1.0);
float Rx = _R1 / ( _Vs / Vout - 1.0);// - Rtest;
float measuredTemperatureNow = 1.08271 * pow(10.0, -13.0) * (3.12508 * pow(10.0, 16.0) - 5.65566 * pow(10.0, 6.0) * sqrt(3.51501 * pow(10.0, 19.0) - 4.61805 * pow(10.0, 16.0) * Rx));
float temperatureDiff = measuredTemperatureNow - _temperatureAverage; // Calculate deviation between temperature reading and average temperature
_temperatureMeasurementsMarker++; // Position reading buffer marker at the last updated position
if(_temperatureMeasurementsMarker >= TEMPERATURE_AVERAGE_VALUE_I) _temperatureMeasurementsMarker = 0; // Check that it has not gone out of the buffer range
if( _temperatureMeasurements[_temperatureMeasurementsMarker] == 0.0 ) {
// First Run
if ( measuredTemperatureNow > 12.0 ) {
// First Run with good data
_temperatureMeasurements[_temperatureMeasurementsMarker] = measuredTemperatureNow;
}
return;
}
/*
if(temperatureDiff > 5 || temperatureDiff < 5) {
_temperatureMeasurements[_temperatureMeasurementsMarker] = measuredTemperatureNow; // Write the average temp + one third of the measured temperature deviation
}
else {
_temperatureMeasurements[_temperatureMeasurementsMarker] = _temperatureAverage + (temperatureDiff / 3.0); // Write the average temp + one third of the measured temperature deviation
}
*/
//_temperatureMeasurements[_temperatureMeasurementsMarker] = measuredTemperatureNow;
_temperatureMeasurements[_temperatureMeasurementsMarker] = _temperatureAverage + (temperatureDiff / 3.0); // Write the average temp + one third of the measured temperature deviation
_temperatureAverage = 0.0; // Zero out the average, it is time to calculate the new one
for(int markerCounter = 0; markerCounter < TEMPERATURE_AVERAGE_VALUE_I; markerCounter++) { // Iterate over the temperature values in the buffer
_temperatureAverage += _temperatureMeasurements[markerCounter]; // Sum all the temperature values
}
_temperatureAverage = _temperatureAverage / TEMPERATURE_AVERAGE_VALUE_F; // Divide the sum by the number of values summed.
_measuredTemperature = _temperatureAverage; // Set the measured temperature to the calculated average value
xFilterNoise(_temperatureMeasurementsMarker);
/*
Serial.print("PT100 : [");
Serial.print(_name);
Serial.print("]\tVoutSample: [");
Serial.print(_VoutAnalogSample);
// Serial.print("]\tVout[");
// Serial.print(Vout,6);
// Serial.print("]\tRx[");
// Serial.print(Rx,6);
Serial.print("]\tTNow[");
Serial.print(measuredTemperatureNow,6);
Serial.print("]\tTCalc[");
Serial.print(_measuredTemperature,6);
Serial.println("] ");
*/
//Serial.print("PT100 : [");
#ifdef DEBUG
Serial.print(_name);
Serial.print(",");
Serial.print(_VoutAnalogSample);
Serial.print(",");
/*Serial.print(test);
Serial.print(",");
Serial.print(Rtest);
Serial.print(",");*/
/*Serial.print(Vout,6);
Serial.print(",");
Serial.print(Rx,6);
Serial.print(",");
Serial.print(measuredTemperatureNow,6);
Serial.print(",");
Serial.print(_measuredTemperature,6);
Serial.print(",");*/
if(ln) Serial.println("");
#endif
}
}
void PT100::measure1(boolean ln, boolean rline) {
if(millis() - _lastTemperatureRead >= _TimeBetweenReadings) { //time to measure temperature
/** measure Vout analog sample */
digitalWrite(_OutputPin_SensorPower, HIGH); // initialize sensor on
digitalWrite(_OutputPin_ThirdLinePower, HIGH); // initialize sensor on
delay(10);
_VoutAnalogSample = analogRead(_InputPin_TemperatureReading) + _sampleDeviation; // Get a reading
_VoutRAnalogSample = analogRead(_InputPin_ThirdLineReading) + _sampleDeviation; // Get a reading
digitalWrite(_OutputPin_SensorPower, LOW); // initialize sensor on
digitalWrite(_OutputPin_ThirdLinePower, LOW); // initialize sensor on
_lastTemperatureRead = millis(); // Mark time of temperature reading
_rPT100MeasurementsMarker++; // Position reading buffer marker at the last updated position
if(_rPT100MeasurementsMarker >= TEMPERATURE_AVERAGE_VALUE_I) _rPT100MeasurementsMarker = 0; // Check that it has not gone out of the buffer range
_rPT100Measurements[_rPT100MeasurementsMarker] = _VoutAnalogSample;
float Vout = GetMedian(_rPT100Measurements) * _ADCVmax / CONSTANT_ADC_STEP_COUNT;
float Rx = _R1 / ( _Vs / Vout - 1.0);
if(rline) {
_rLineMeasurementsMarker++; // Position reading buffer marker at the last updated position
if(_rLineMeasurementsMarker >= TEMPERATURE_AVERAGE_VALUE_I) _rLineMeasurementsMarker = 0; // Check that it has not gone out of the buffer range
_rLineMeasurements[_rLineMeasurementsMarker] = _VoutRAnalogSample;
/** Calculate temperature value */
float VoutR = GetMedian(_rLineMeasurements) * _ADCVmax / CONSTANT_ADC_STEP_COUNT;
float Rline = _R2 / ( _Vs / VoutR - 1.0);
_measuredTemperature = 1.08271 * pow(10.0, -13.0) * (3.12508 * pow(10.0, 16.0) - 5.65566 * pow(10.0, 6.0) * sqrt(3.51501 * pow(10.0, 19.0) - 4.61805 * pow(10.0, 16.0) * (Rx - Rline)));
}
else {
/** Calculate temperature value */
_measuredTemperature = 1.08271 * pow(10.0, -13.0) * (3.12508 * pow(10.0, 16.0) - 5.65566 * pow(10.0, 6.0) * sqrt(3.51501 * pow(10.0, 19.0) - 4.61805 * pow(10.0, 16.0) * Rx));
}
//xFilterNoise(_temperatureMeasurementsMarker);
/*
Serial.print("PT100 : [");
Serial.print(_name);
Serial.print("]\tVoutSample: [");
Serial.print(_VoutAnalogSample);
// Serial.print("]\tVout[");
// Serial.print(Vout,6);
// Serial.print("]\tRx[");
// Serial.print(Rx,6);
Serial.print("]\tTNow[");
Serial.print(measuredTemperatureNow,6);
Serial.print("]\tTCalc[");
Serial.print(_measuredTemperature,6);
Serial.println("] ");
*/
//Serial.print("PT100 : [");
#ifdef DEBUG
Serial.print(_name);
Serial.print(",");
Serial.print(_VoutAnalogSample);
Serial.print(",");
//Serial.print(_VoutRAnalogSample);
//Serial.print(",");
/*Serial.print(test);
Serial.print(",");
Serial.print(Rtest);
Serial.print(",");*/
/*Serial.print(Vout,6);
Serial.print(",");
Serial.print(Rx,6);
Serial.print(",");
Serial.print(measuredTemperatureNow,6);
Serial.print(",");
Serial.print(_measuredTemperature,6);
Serial.print(",");*/
if(ln) Serial.println("");
#endif
}
}
float PT100::GetMedian(int array[]){
int sorted[TEMPERATURE_AVERAGE_VALUE_I];
float value = 0.0;
for(int x = 0; x < TEMPERATURE_AVERAGE_VALUE_I; x++) {
sorted[x] = array[x];
}
//ARRANGE VALUES
for(int x = 0; x < TEMPERATURE_AVERAGE_VALUE_I; x++){
for(int y = 0; y < TEMPERATURE_AVERAGE_VALUE_I - 1; y++){
if(sorted[y]>sorted[y+1]){
int temp = sorted[y+1];
sorted[y+1] = sorted[y];
sorted[y] = temp;
}
}
}
//CALCULATE THE MEDIAN (middle number)
if(TEMPERATURE_AVERAGE_VALUE_I % 2 != 0){// is the # of elements odd?
int temp = ((TEMPERATURE_AVERAGE_VALUE_I+1)/2)-1;
value = (float) sorted[temp];
}
else{// then it's even! :)
value = ((float) ( sorted[(TEMPERATURE_AVERAGE_VALUE_I/2)-1] + sorted[TEMPERATURE_AVERAGE_VALUE_I/2] )) / 2.0;
}
return value;
}
float PT100::GetMode(float new_array[]) {
int ipRepetition[TEMPERATURE_AVERAGE_VALUE_I];
for (int i = 0; i < TEMPERATURE_AVERAGE_VALUE_I; i++) {
ipRepetition[i] = 0;//initialize each element to 0
int j = 0;//
while ((j < i) && (new_array[i] != new_array[j])) {
if (new_array[i] != new_array[j]) {
j++;
}
}
(ipRepetition[j])++;
}
int iMaxRepeat = 0;
for (int i = 1; i < TEMPERATURE_AVERAGE_VALUE_I; i++) {
if (ipRepetition[i] > ipRepetition[iMaxRepeat]) {
iMaxRepeat = i;
}
}
return new_array[iMaxRepeat];
}
/*
void PT100::mean(int new_array[], int num){
//GET TOTAL & CALCULATE MEAN
float total;
for(int i=0;i<num; i++){
total += new_array[i];
}
cout << "The mean is " << total/num << endl;
mode(new_array, num);
}
void PT100::median(int new_array[], int num){
//CALCULATE THE MEDIAN (middle number)
if(num % 2 != 0){// is the # of elements odd?
int temp = ((num+1)/2)-1;
cout << "The median is " << new_array[temp] << endl;
}
else{// then it's even! :)
cout << "The median is "<< new_array[(num/2)-1] << " and " << new_array[num/2] << endl;
}
mean(new_array, num);
}*/
void PT100::xFilterNoise( int position ) {
for( int i = 0; i < 10 ; i++ ) {
int first = (position - 2 - i < 0)?(position - 2 - i + TEMPERATURE_AVERAGE_VALUE_I):(position - 2 - i);
int second = (position - 1 - i < 0)?(position - 1 - i + TEMPERATURE_AVERAGE_VALUE_I):(position - 1 - i);
int third = (position - i < 0)?(position - i + TEMPERATURE_AVERAGE_VALUE_I):(position - i);
if(
( ( _temperatureMeasurements[second] > _temperatureMeasurements[first] ) && ( _temperatureMeasurements[second] > _temperatureMeasurements[third] ) )
||
( ( _temperatureMeasurements[second] < _temperatureMeasurements[first] ) && ( _temperatureMeasurements[second] < _temperatureMeasurements[third] ) )
)
{
_temperatureMeasurements[second] = ( _temperatureMeasurements[first] + _temperatureMeasurements[third] ) / 2;
}
}
}
float PT100::getCurrentTemperature() {
float y = __m * _measuredTemperature + __b;
return _measuredTemperature + y + _measuredTemperatureDeviation; // - 4.41;
}
float PT100::getMeasuredTemperatureDeviation() {
return _measuredTemperatureDeviation; // - 4.41;
}
float PT100::setMeasuredTemperatureDeviation( float measuredTemperatureDeviation) {
if( _measuredTemperatureDeviation != measuredTemperatureDeviation ) {
_measuredTemperatureDeviation = measuredTemperatureDeviation;
for( int i = 0; i < TEMPERATURE_AVERAGE_VALUE_I; i++ ) {
_temperatureMeasurements[i] = _temperatureMeasurements[i] + ( _measuredTemperatureDeviation * -1 );
}
}
return _measuredTemperatureDeviation; // - 4.41;
}
float PT100::setSampleDeviation( float sampleDeviation) {
_sampleDeviation = sampleDeviation;
return _sampleDeviation;
}
\ No newline at end of file
PT100.h 0 → 100644
View file @ 093e6051
/*
PT100.h - Library for measuring temperature with a PT100.
Created by João Lino, June 24, 2015.
Released into the public domain.
*/
#ifndef PT100_h
#define PT100_h
#include "Arduino.h"
#define DEBUG
#define CONSTANT_ADC_STEP_COUNT 1024.0
#define TEMPERATURE_AVERAGE_VALUE_I 50
#define TEMPERATURE_AVERAGE_VALUE_F 50.0
//#define TEMPERATURE_AVERATE_INIT_VALUES 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0
#define TEMPERATURE_AVERATE_INIT_VALUES 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0
#define TEMPERATURE_AVERATE_INIT_VALUES_I 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
#define TEMPERATURE_SETTING_MAX_VALUE 120
class PT100
{
public:
// PT100(PT100_OUTPUT_PIN, PT100_INPUT_PIN, PT100_TIME_BETWEEN_READINGS, PT100_DEFAULT_ADC_VMAX, PT100_DEFAULT_VS, PT100_DEFAULT_R1_RESISTENCE, PT100_DEFAULT_LINE_RESISTENCE, PT100_DEFAULT_OPERATION_RESISTENCE);
PT100(char *name,
int OutputPin_SensorPower,
int OutputPin_ThirdLinePower,
int InputPin_TemperatureReading,
int InputPin_ThirdLineReading,
int TimeBetweenReadings = 100,
float ADCVmax = 1.081,
float Vs = 4.87,
float R1 = 606.0,
float R2 = 606.0,
float m = 1.0,
float b = 0.0);
void setPower(float ADCVmax = 1.081, float Vs = 4.87);
void measure(boolean ln);
void measure1(boolean ln, boolean rline);
void safeHardwarePowerOff();
float getCurrentTemperature();
float getMeasuredTemperatureDeviation();
float setMeasuredTemperatureDeviation( float measuredTemperatureDeviation);
float setSampleDeviation( float sampleDeviation);
private:
char *_name;
int _OutputPin_SensorPower;
int _OutputPin_ThirdLinePower;
int _InputPin_TemperatureReading;
int _InputPin_ThirdLineReading;
int _TimeBetweenReadings;
float _ADCVmax;
float _Vs;
float _R1;
float _R2;
float __m;
float __b;
float _temperatureAverage;
float _measuredTemperature;
float _measuredTemperatureDeviation;
float _sampleDeviation;
unsigned long _lastTemperatureRead;
int _VoutAnalogSample;
int _VoutRAnalogSample;
float _VoutPreviousAnalogSample;
int _temperatureMeasurementsMarker;
int _rPT100MeasurementsMarker;
int _rLineMeasurementsMarker;
float _temperatureMeasurements[TEMPERATURE_AVERAGE_VALUE_I] = {TEMPERATURE_AVERATE_INIT_VALUES};
int _rPT100Measurements[TEMPERATURE_AVERAGE_VALUE_I] = {TEMPERATURE_AVERATE_INIT_VALUES_I};
int _rLineMeasurements[TEMPERATURE_AVERAGE_VALUE_I] = {TEMPERATURE_AVERATE_INIT_VALUES_I};
void xFilterNoise( int position );
float GetMedian(int array[]);
float GetMode(float array[]);
};
#endif
\ No newline at end of file
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