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Code Part

My current Code

If it doesn't show it is because I forgot to merge my code branch with my doc branch.
You might want to go the the git page than.

Temperature

VMA 320

The source of the code.

The manual of my thermoresistor.

I also added a Capa to the circuit based on this article.

I change 1023 to 4095 (the bit definition of the ADC).

And contrary to the manual the sensor is on 3.3V.

Check Week04 for the full story.

Circuit

Example
Temperature Sensor - VMA 320
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void TempS(int pin){
float reading;

// The beta coefficient of the thermistor (usually 3000-4000)
#define BCOEFFICIENT 3950
// the value of the 'other' resistor
#define SERIESRESISTOR 10000     
// resistance at 25 degrees C
#define THERMISTORNOMINAL 10000      
// temp. for nominal resistance (almost always 25 C)
#define TEMPERATURENOMINAL 25 

reading  = analogRead(pin);

reading = 4095 / reading - 1;
reading = SERIESRESISTOR / reading;
Serial.print("Thermistor resistance "); 
Serial.println(reading);

float steinhart;
steinhart = reading / THERMISTORNOMINAL;     // (R/Ro)
steinhart = log(steinhart);                  // ln(R/Ro)
steinhart /= BCOEFFICIENT;                   // 1/B * ln(R/Ro)
steinhart += 1.0 / (TEMPERATURENOMINAL + 273.15); // + (1/To)
steinhart = 1.0 / steinhart;                 // Invert
steinhart -= 273.15;                         // convert absolute temp to C

Serial.print("Temperature "); 
Serial.print(steinhart);
Serial.println(" *C");
//Originally from: https://learn.adafruit.com/thermistor/using-a-thermistor
}

Sensirion SCD30

Temperature & Humidity & CO2 Sensor

Check at CO2 section

CO2

SGP30

This is a CO2 & VOC sensor

Needed library Adafruit SGP30 and I2C Wire library.

Example
CO2 & VOC Sensor - SGP30
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//
#include <Arduino.h>
// I2C Communication
#include <Wire.h>
// SGP30 - CO2 Sensor
#include "Adafruit_SGP30.h"
Adafruit_SGP30 sgp;

// ---------- Function declaration ----------
void CO2S_SGP30(); //CO2 Sensor
int counter = 0; // Counter for CO2 Sensor
uint32_t getAbsoluteHumidity(float, float); // Absolute humidity correction for CO2 Sensor

// ---------- Setup ----------
void setup() {
// put your setup code here, to run once:

Serial.begin(9600);   // Initialize Serial Monitor
while (!Serial) { delay(10); } // Wait for serial console to open!

// Initialize I2C communication for the SGP30
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);

// If you have a baseline measurement from before you can assign it to start, to 'self-calibrate'
//sgp.setIAQBaseline(0x8E68, 0x8F41);  // Will vary for each sensor!
}


// ---------- Loop ----------
void loop() {

CO2S_SGP30();
delay(5000);
}


// ---------- Function definitions ----------
// ---------- CO2 Sensor - Sensirion SGP30 eCO2 & TVOC Sensor

/* return absolute humidity [mg/m^3] with approximation formula
* @param temperature [°C]
* @param humidity [%RH]
*/
uint32_t getAbsoluteHumidity(float temperature, float humidity) {
// approximation formula from Sensirion SGP30 Driver Integration chapter 3.15
const float absoluteHumidity = 216.7f * ((humidity / 100.0f) * 6.112f * exp((17.62f * temperature) / (243.12f + temperature)) / (273.15f + temperature)); // [g/m^3]
const uint32_t absoluteHumidityScaled = static_cast<uint32_t>(1000.0f * absoluteHumidity); // [mg/m^3]
return absoluteHumidityScaled;
}


void CO2S_SGP30(){
// If you have a temperature / humidity sensor, you can set the absolute humidity to enable the humidity 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);
}
//Code from Adafruit SGP30 example
}

Sensirion SCD30

This is a CO2, Humidity and Temperature Sensor

SCD30
CO2, Temperature & Humidity Sensor - SCD30
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// SCD30 - CO2 Sensor
#include "SparkFun_SCD30_Arduino_Library.h"
SCD30 airSensor;

// SCD30 - CO2 Sensor
void CO2S_SCD30_STAR(bool); //function to initialize the CO2 Sensor - SCD30
void CO2S_SCD30(); //CO2 Sensor - SCD30

void setup() {
    // put your setup code here, to run once:

    Serial.begin(9600);   // Initialize Serial Monitor
    while (!Serial) { delay(10); } // Wait for serial console to open!
    // Initialize the CO2 Sensor - SCD30
    CO2S_SCD30_STAR(true);
}

void loop() {
    CO2S_SCD30();
}

// ---------- CO2, T and Humidity Sensor - Sensirion SCD30

void CO2S_SCD30_STAR(bool initialize){
Serial.println("SCD30 Example");
    Wire.begin(); // Initialize I2C communication

    //Start sensor using the Wire port, but disable the auto-calibration
    if (airSensor.begin(Wire, false) == false){
        Serial.println("Air sensor not detected. Please check wiring. Freezing...");
        while (1); // Do nothing more
    }

    uint16_t settingVal; // The settings will be returned in settingVal

    if (airSensor.getForcedRecalibration(&settingVal) == true){ // Get the setting
        Serial.print("Forced recalibration factor (ppm) is ");
        Serial.println(settingVal);
    }
    else{
        Serial.print("getForcedRecalibration failed! Freezing...");
        while (1); // Do nothing more
    }

    if (airSensor.getMeasurementInterval(&settingVal) == true){ // Get the setting
        Serial.print("Measurement interval (s) is ");
        Serial.println(settingVal);
    }
    else{
        Serial.print("getMeasurementInterval failed! Freezing...");
        while (1); // Do nothing more
    }

    if (airSensor.getTemperatureOffset(&settingVal) == true){ // Get the setting
        Serial.print("Temperature offset (C) is ");
        Serial.println(((float)settingVal) / 100.0, 2);
    }
    else{
        Serial.print("getTemperatureOffset failed! Freezing...");
        while (1); // Do nothing more
    }

    if (airSensor.getAltitudeCompensation(&settingVal) == true){ // Get the setting
        Serial.print("Altitude offset (m) is ");
        Serial.println(settingVal);
    }
    else{
        Serial.print("getAltitudeCompensation failed! Freezing...");
        while (1)
        ; // Do nothing more
    }

    if (airSensor.getFirmwareVersion(&settingVal) == true){ // Get the setting
        Serial.print("Firmware version is 0x");
        Serial.println(settingVal, HEX);
    }
    else{
        Serial.print("getFirmwareVersion! Freezing...");
        while (1); // Do nothing more
    }

    Serial.print("Auto calibration set to ");
    if (airSensor.getAutoSelfCalibration() == true)
        Serial.println("true");
    else
        Serial.println("false");

//The SCD30 has data ready every two seconds
}

void CO2S_SCD30(){
    if (airSensor.dataAvailable())
    {
        Serial.print("co2(ppm):");
        Serial.print(airSensor.getCO2());

        Serial.print(" temp(C):");
        Serial.print(airSensor.getTemperature(), 1);

        Serial.print(" humidity(%):");
        Serial.print(airSensor.getHumidity(), 1);

        Serial.println();
    }
    else
        Serial.println("Waiting for new data");

    delay(500);
}
//Code from Adafruit example

Check Week09 for the full story.

Documentation & Sources:

MTP40-F

Humidity

Sensirion SCD30

Temperature & Humidity & CO2 Sensor

Check at CO2 section

Volatile Organic Compound (VOC)

SGP30

This is a CO2 & VOC sensor

Check at CO2 section

Screen

OLED

OLED
OLED
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//
#include <Arduino.h>

// I2C Communication
#include <Wire.h>

// For the OLED Display
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
//#include <SPI.h>
#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 32 // OLED display height, in pixels
#define OLED_RESET     -1 // Reset pin # (or -1 if sharing Arduino reset pin)
#define SCREEN_ADDRESS 0x3C ///< See datasheet for Address; 0x3D for 128x64, 0x3C for 128x32
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
#include <Fonts/FreeSerif12pt7b.h>

// ---------- Function declaration ----------
// OLED Display
void OLED_STAR(bool initialize); //function to initialize the OLED Display
void OLED_DISPLAY(); //function to display the data on the OLED Display

// ---------- Setup ----------
void setup() {
// put your setup code here, to run once:
Wire.begin(); // Initialize I2C communication

Serial.begin(9600);   // Initialize Serial Monitor
while (!Serial) { delay(10); } // Wait for serial console to open!

// Initialize the OLED Display
OLED_STAR(true);

}


// ---------- Loop ----------
void loop() {  

OLED_DISPLAY();

}


// ---------- Function definitions ----------
// ---------- OLED Display
void OLED_STAR(bool initialize){
// 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
}
// Show initial display buffer contents on the screen --
// the library initializes this with an Adafruit splash screen.
display.display();
delay(2000); // Pause for 2 seconds

// Clear the buffer
display.clearDisplay();
}
void OLED_DISPLAY(){
// Clear the display buffer
display.clearDisplay();

// Text Settings
display.setTextSize(1); // Normal 1:1 pixel scale
display.setFont(); // Choose a font
display.setTextColor(WHITE); // Draw white text
display.setCursor(0, 0); // Start at top-left corner
display.setRotation(2); // Rotate the display 0 to 3 times 90 degrees

// Display static text test
display.print("Hello, World!");

// Display the buffer contents on the screen
display.display();
}

Documentation & Sources:

Communication

I2C

I2C Scanner
I2C Scanner
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//
#include <Arduino.h>

// I2C Communication
#include <Wire.h>

// ---------- Function declaration ----------
// I2C Scanner
void I2C_Scan(); //I2C Scanner, no Pin required, To check I2C devices connected to the board

// ---------- Setup ----------
void setup() {
// put your setup code here, to run once:
Wire.begin(); // Initialize I2C communication

Serial.begin(9600);   // Initialize Serial Monitor
while (!Serial) { delay(10); } // Wait for serial console to open!

}


// ---------- Loop ----------
void loop() {  

I2C_Scan();

}


// ---------- Function definitions ----------
// ---------- I2C Scanner
void I2C_Scan() {
byte error, address;
int nDevices;
Serial.println("Scanning...");
nDevices = 0;
for(address = 1; address < 127; address++ ) {
    Wire.beginTransmission(address);
    error = Wire.endTransmission();
    if (error == 0) {
    Serial.print("I2C device found at address 0x");
    if (address<16) {
        Serial.print("0");
    }
    Serial.println(address,HEX);
    nDevices++;
    }
    else if (error==4) {
    Serial.print("Unknow error at address 0x");
    if (address<16) {
        Serial.print("0");
    }
    Serial.println(address,HEX);
    }    
}
if (nDevices == 0) {
    Serial.println("No I2C devices found\n");
}
else {
    Serial.println("done\n");
}
delay(5000);          
}

Documentation & Sources:

MESH

Safe keep: