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/**************************************************************************
 This is an example for our Monochrome OLEDs based on SSD1306 drivers
  Pick one up today in the adafruit shop!
 ------> http://www.adafruit.com/category/63_98
  This example is for a 128x64 pixel display using I2C to communicate
 3 pins are required to interface (two I2C and one reset).
  Adafruit invests time and resources providing this open
 source code, please support Adafruit and open-source
 hardware by purchasing products from Adafruit!
  Written by Limor Fried/Ladyada for Adafruit Industries,
 with contributions from the open source community.
 BSD license, check license.txt for more information
 All text above, and the splash screen below must be
 included in any redistribution.
 **************************************************************************/
 #include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include "Adafruit_SGP30.h"
 #define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels
 // Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
#define OLED_RESET     -1 // Reset pin # (or -1 if sharing Arduino reset pin)
#define SCREEN_ADDRESS 0x3C 
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
 // Declaration for an SGP30 display connected to I2C (SDA, SCL pins)
Adafruit_SGP30 sgp;
 int counter = 0;
int fanPin = 9;
 void setup() {
  Serial.begin(9600);
    pinMode(fanPin, OUTPUT);
   // SSD1306_SWITCHCAPVCC = generate display voltage from 3.3V internally
  if(!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;); // Don't proceed, loop forever
  }
   while (!Serial) { delay(10); } // Wait for serial console to open!
   Serial.println("SGP30 test");
   if (! sgp.begin()){
    Serial.println("Sensor not found :(");
    while (1);
  }
  Serial.print("Found SGP30 serial #");
  Serial.print(sgp.serialnumber[0], HEX);
  Serial.print(sgp.serialnumber[1], HEX);
  Serial.println(sgp.serialnumber[2], HEX);
   // Clear the buffer
  display.clearDisplay();
  display.display();
  delay(2000);
    testdrawtriangle();  // Draw triangles (outlines)
   testdrawchar();      // Draw characters of the default font
}
  void loop() {
    // If you have a temperature / humidity sensor, you can set the absolute humidity to enable the humditiy compensation for the air quality signals
  //float temperature = 22.1; // [°C]
  //float humidity = 45.2; // [%RH]
  //sgp.setHumidity(getAbsoluteHumidity(temperature, humidity));
   if (! sgp.IAQmeasure()) {
    Serial.println("Measurement failed");
    return;
  }
  Serial.print("TVOC "); Serial.print(sgp.TVOC); Serial.print(" ppb\t");
  Serial.print("eCO2 "); Serial.print(sgp.eCO2); Serial.println(" ppm");
   if (! sgp.IAQmeasureRaw()) {
    Serial.println("Raw Measurement failed");
    return;
  }
  Serial.print("Raw H2 "); Serial.print(sgp.rawH2); Serial.print(" \t");
  Serial.print("Raw Ethanol "); Serial.print(sgp.rawEthanol); Serial.println("");
   delay(1000);
   counter++;
  if (counter == 30) {
    counter = 0;
     uint16_t TVOC_base, eCO2_base;
    if (! sgp.getIAQBaseline(&eCO2_base, &TVOC_base)) {
      Serial.println("Failed to get baseline readings");
      return;
    }
    Serial.print("****Baseline values: eCO2: 0x"); Serial.print(eCO2_base, HEX);
    Serial.print(" & TVOC: 0x"); Serial.println(TVOC_base, HEX);
  }
   // Fan off  
  analogWrite(fanPin, 0);
  delay(3000);
   // Medium speed
  analogWrite(fanPin, 150);
  delay(3000);
   // Max speed
  analogWrite(fanPin, 255);
  delay(3000);
}
 void testdrawtriangle(void) {
  display.clearDisplay();
   for(int16_t i=0; i<max(display.width(),display.height())/2; i+=5) {
    display.drawTriangle(
      display.width()/2  , display.height()/2-i,
      display.width()/2-i, display.height()/2+i,
      display.width()/2+i, display.height()/2+i, SSD1306_WHITE);
    display.display();
    delay(1);
  }
   delay(2000);
}
  void testdrawchar(void) {
  display.clearDisplay();
   display.setTextSize(2);      // Normal 1:1 pixel scale
  display.setTextColor(SSD1306_WHITE); // Draw white text
  display.setCursor(0, 0);     // Start at top-left corner
 display.cp437(true);  // Use correct CP437 character codes
 display.printf("TVOC: %d ppb\n", sgp.TVOC);
display.printf("eCO2: %d ppm\n", sgp.eCO2);
 display.println();    // New line
  display.display();
  delay(2000);
}