// Arduino Sample Code
// Non conforme : A modifier
void setup()
{
  Serial.begin(9600); // Set serial baud rate to 9600 bps
}
void loop()
{
int val;
val=analogRead(0); //  Read Gas value from analog 0
Serial.println(val,DEC);// Print the value to serial port
delay(100);
}

/*******************Demo for MG-811 Gas Sensor Module V1.1*****************************
Author:  Tiequan Shao: tiequan.shao@sandboxelectronics.com
         Peng Wei:     peng.wei@sandboxelectronics.com
 
Lisence: Attribution-NonCommercial-ShareAlike 3.0 Unported (CC BY-NC-SA 3.0)
 
Note:    This piece of source code is supposed to be used as a demostration ONLY. More
         sophisticated calibration is required for industrial field application. 
 
                                                    Sandbox Electronics    2012-05-31
************************************************************************************/
 
/************************Hardware Related Macros************************************/
#define         MG_PIN                       (A0)     //define which analog input channel you are going to use
#define         BOOL_PIN                     (2)
#define         DC_GAIN                      (8.5)   //define the DC gain of amplifier
 
/***********************Software Related Macros************************************/
#define         READ_SAMPLE_INTERVAL         (50)    //define how many samples you are going to take in normal operation
#define         READ_SAMPLE_TIMES            (5)     //define the time interval(in milisecond) between each samples in 
                                                     //normal operation
 
/**********************Application Related Macros**********************************/
//These two values differ from sensor to sensor. user should derermine this value.
#define         ZERO_POINT_VOLTAGE           (0.220) //define the output of the sensor in volts when the concentration of CO2 is 400PPM
#define         REACTION_VOLTGAE             (0.030) //define the voltage drop of the sensor when move the sensor from air into 1000ppm CO2
 
/*****************************Globals***********************************************/
float           CO2Curve[3]  =  {2.602,ZERO_POINT_VOLTAGE,(REACTION_VOLTGAE/(2.602-3))};   
                                                     //two points are taken from the curve. 
                                                     //with these two points, a line is formed which is
                                                     //"approximately equivalent" to the original curve.
                                                     //data format:{ x, y, slope}; point1: (lg400, 0.324), point2: (lg4000, 0.280) 
                                                     //slope = ( reaction voltage ) / (log400 –log1000) 
 
void setup()
{
    Serial.begin(9600);                              //UART setup, baudrate = 9600bps
    pinMode(BOOL_PIN, INPUT);                        //set pin to input
    digitalWrite(BOOL_PIN, HIGH);                    //turn on pullup resistors
 
   Serial.print("MG-811 Demostration\n");                
}
 
void loop()
{
    int percentage;
    float volts;
 
    volts = MGRead(MG_PIN);
    Serial.print( "SEN0159:" );
    Serial.print(volts); 
    Serial.print( "V           " );
 
    percentage = MGGetPercentage(volts,CO2Curve);
    Serial.print("CO2:");
    if (percentage == -1) {
        Serial.print( "<400" );
    } else {
        Serial.print(percentage);
    }
 
    Serial.print( "ppm" );  
    Serial.print("\n");
 
    if (digitalRead(BOOL_PIN) ){
        Serial.print( "=====BOOL is HIGH======" );
    } else {
        Serial.print( "=====BOOL is LOW======" );
    }
 
    Serial.print("\n");
 
    delay(500);
}
 
/*****************************  MGRead *********************************************
Input:   mg_pin - analog channel
Output:  output of SEN-000007
Remarks: This function reads the output of SEN-000007
************************************************************************************/ 
float MGRead(int mg_pin)
{
    int i;
    float v=0;
 
    for (i=0;i<READ_SAMPLE_TIMES;i++) {
        v += analogRead(mg_pin);
        delay(READ_SAMPLE_INTERVAL);
    }
    v = (v/READ_SAMPLE_TIMES) *5/1024 ;
    return v;  
}
 
/*****************************  MQGetPercentage **********************************
Input:   volts   - SEN-000007 output measured in volts
         pcurve  - pointer to the curve of the target gas
Output:  ppm of the target gas
Remarks: By using the slope and a point of the line. The x(logarithmic value of ppm) 
         of the line could be derived if y(MG-811 output) is provided. As it is a 
         logarithmic coordinate, power of 10 is used to convert the result to non-logarithmic 
         value.
************************************************************************************/ 
int  MGGetPercentage(float volts, float *pcurve)
{
   if ((volts/DC_GAIN )>=ZERO_POINT_VOLTAGE) {
      return -1;
   } else { 
      return pow(10, ((volts/DC_GAIN)-pcurve[1])/pcurve[2]+pcurve[0]);
   }
}

// Matériels : Adafruit Feather Huzzah ESP8266  + Support Particle, Adafruit OLED SH1107, Adafruit SGP30, câble Qwiic.
// Logiciel : Arduino
 
// Bibliothèques
#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SH110X.h>
#include "Adafruit_SGP30.h"
 
#define BUTTON_A 0
#define BUTTON_B 16
#define BUTTON_C 2
 
// Constructeurs
Adafruit_SH1107 display = Adafruit_SH1107(64, 128, &Wire);
Adafruit_SGP30 sgp;
 
void setup()
{
  // Bus I2C
  Wire.begin(); // Initialisation
  Wire.setClock(400000);
  display.begin(0x3C, true); // L'adresse de l'afficheur est 0x3C par défaut
 
  // Configuration de l'affichage
  display.setRotation(1); // Affichage horizontal
  display.setTextSize(1);
  display.setTextColor(SH110X_WHITE);
  display.clearDisplay(); // Pour ne pas afficher le logo Adafruit chargé
                          // automatiquement à la mise sous tension
 
  // Test de la communication avec le capteur
  if (!sgp.begin())
  {
    display.println("Le capteur de repond pas");
    while (1)
      ;
  }
  display.print("Numero de serie #");
  display.print(sgp.serialnumber[0], HEX);
  display.print(sgp.serialnumber[1], HEX);
  display.println(sgp.serialnumber[2], HEX);
  display.display(); // Transfert du buffer sur l'écran
  delay(2000);
 
  // Connexion des boutons-poussoirs
  pinMode(BUTTON_A, INPUT_PULLUP);
  pinMode(BUTTON_B, INPUT_PULLUP);
  pinMode(BUTTON_C, INPUT_PULLUP);
}
 
void loop()
{
  // Efface le buffer
  display.clearDisplay();
 
  // Test des boutons
  display.setCursor(0, 0);
 
  if (!digitalRead(BUTTON_A))
    display.print("[A]");
  if (!digitalRead(BUTTON_B))
    display.print("[B]");
  if (!digitalRead(BUTTON_C))
    display.print("[C]");
 
  // Titre
  display.setCursor(40, 0);
  display.println("SGP30");
 
  // Numéro de série
  display.setCursor(0, 12);
  display.print("Numero : #");
  display.print(sgp.serialnumber[0], HEX);
  display.print(sgp.serialnumber[1], HEX);
  display.println(sgp.serialnumber[2], HEX);
 
  // Mesures
  if (!sgp.IAQmeasure())
  {
    Serial.println("Measurement failed");
    return;
  }
 
  // Mesures et affichage
  display.print("TVOC : ");
  display.print(sgp.TVOC);
  display.println(" ppb");
  display.print("eCO2 : ");
  display.print(sgp.eCO2);
  display.println(" ppm");
 
  // Infos
  display.setCursor(5, 52);
  display.print("Appuyer sur A, B, C");
  display.display(); // Transfert du buffer sur l'écran
 
  delay(500);
}