MQ-3 alcohol sensor

MQ-3 sensor profile:

MQ-3 gas sensor is sensitive material used in clean air, low conductivity tin dioxide (SnO2). When the sensor is present in the environment in which the alcohol vapor , the sensor's conductivity increases with the concentration of alcohol gas in the air increases. Using a simple circuit can be converted to the change in conductivity of the gas concentration with the corresponding output signal. MQ-3 gas sensor with high sensitivity to alcohol , gasoline can resist , smoke , water vapor interference. This sensor can detect various concentrations of alcohol atmosphere , is a low-cost sensors for a variety of applications

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Code การวัดค่าแสดงผล

#include
#include
#include
#include

#define OLED_RESET 4
int TIME_UNTIL_WARMUP = 900;
unsigned long time;


int analogPin = 0;
int val = 0;
Adafruit_SSD1306 display(OLED_RESET);


void setup() {

display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
display.clearDisplay();
}


void loop() {

delay(100);

val = readAlcohol();
printTitle();
printWarming();

time = millis()/1000;

if(time<=TIME_UNTIL_WARMUP)
{
time = map(time, 0, TIME_UNTIL_WARMUP, 0, 100);
display.drawRect(10, 50, 110, 10, WHITE); //Empty Bar
display.fillRect(10, 50, time,10,WHITE);
}else
{
printTitle();
printAlcohol(val);
printAlcoholLevel(val);
}
display.display();

}


void printTitle()
{
display.clearDisplay();
display.setTextSize(1);
display.setTextColor(WHITE);
display.setCursor(22,0);
display.println("Breath Analyzer");
}

void printWarming()
{
display.setTextSize(2);
display.setTextColor(WHITE);
display.setCursor(0,20);
display.println("Warming up");
}

void printAlcohol(int value)
{
display.setTextSize(2);
display.setTextColor(WHITE);
display.setCursor(45,25);
display.println(val);
}

void printAlcoholLevel(int value)
{
display.setTextSize(1);
display.setTextColor(WHITE);
display.setCursor(10,55);

if(value<200)
{
display.println("You are sober.");
}
if (value>=200 && value<280)
{
display.println("You had a beer.");
}
if (value>=280 && value<350)
{
display.println("Two or more beers.");
}
if (value>=350 && value <450)
{
display.println("I smell Oyzo!");
}
if(value>450)
{
display.println("You are drunk!");
}
}

int readAlcohol()
{
int val = 0;
int val1;
int val2;
int val3;


display.clearDisplay();
val1 = analogRead(analogPin);
delay(10);
val2 = analogRead(analogPin);
delay(10);
val3 = analogRead(analogPin);

val = (val1+val2+val3)/3;
return val;
}