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--- iothings:proiecte:2023sric:alcoholbreath [2024/05/30 08:33]
dumitru_razvan.dinu
+++ iothings:proiecte:2023sric:alcoholbreath [2024/05/30 08:38] (current)
dumitru_razvan.dinu
@@ Line 49: / Line 49: @@
 {{:iothings:proiecte:2023sric:app_mob.png?450|}}
+<code>
+#include <DHT.h>
+#include <Wire.h>
+#include "BluetoothSerial.h"
+#include <LiquidCrystal.h>
+#define MQ3_PIN 35
+#define DHT_PIN 4
+#define DHT_TYPE DHT11
+#define BUZZER_PIN 14
+#define rs 16
+#define E 17
+#define D4 18
+#define D5 19
+#define D6 21
+#define D7 22
+#define V0 23
+LiquidCrystal lcd(rs, E, D4, D5, D6, D7);
+BluetoothSerial SerialBT;
+DHT dht(DHT_PIN, DHT_TYPE);
+char received;
+const float RL = 10.0;
+const int NUM_READINGS = 100;
+const int COLLECTION_PERIOD = 10000;
+float R0;
+bool startCollection = false;
+void setup() {
+  SerialBT.begin("ESP32_Alcohol_Test");
+  Serial.begin(115200);
+  pinMode(MQ3_PIN, INPUT);
+  pinMode(BUZZER_PIN, OUTPUT);
+  digitalWrite(BUZZER_PIN, LOW);
+  dht.begin();
+  lcd.begin(16, 2);
+  lcd.print("Initializing...");
+  pinMode(V0, OUTPUT);
+  analogWrite(V0, 100);
+}
+void loop() {
+  if (SerialBT.available()) {
+    received = SerialBT.read();
+    if (received == 'C') {
+      R0 = calibrateMQ3();
+    } else if (received == 'S') {
+      startCollection = true;
+    }
+  }
+  if (startCollection) {
+    collectAndSendSensorData();
+    startCollection = false;
+  }
+}
+float calibrateMQ3() {
+  R0 = readRS();
+  Serial.print("R0 in clean air: ");
+  Serial.print(R0);
+  Serial.println(" kOhm");
+  lcd.clear();
+  lcd.print("Calibrated");
+  SerialBT.println("Ready to use!");
+  return R0;
+}
+float readRS() {
+  long totalReadings = 0;
+  for (int i = 0; i < NUM_READINGS; i++) {
+    totalReadings += analogRead(MQ3_PIN);
+    delay(100);
+  }
+  int avgReading = totalReadings / NUM_READINGS;
+  float sensorVoltage = avgReading * (3.3 / 4095.0);
+  float RS = ((3.3 * RL) / sensorVoltage) - RL;
+  return RS;
+}
+void collectAndSendSensorData() {
+  digitalWrite(BUZZER_PIN, HIGH);
+  float temperature = dht.readTemperature();
+  float humidity = dht.readHumidity();
+  Serial.println("temperature:  " + String(temperature));
+  Serial.println("humidity:  " + String(humidity));
+  float mq3_value = readRS();
+  if (isnan(temperature) || isnan(humidity)) {
+    Serial.println("Failed to read from DHT sensor!");
+    return;
+  }
+  float alcohol_concentration;
+  float dif = R0 - mq3_value;
+  if (dif < 2) {
+   alcohol_concentration = 0;
+  } else {
+    float compensated = dif / (1 + (0.02 * (temperature - 20)) + (0.05 * (humidity - 65)));
+    alcohol_concentration = calculateAlcoholConcentration(compensated);
+      Serial.println("compensated:  " + String(compensated));
+  }
+  Serial.println("R0:  " + String(R0));
+  Serial.println("Mq-3:  " + String(mq3_value));
+  Serial.println("dif:  " + String(dif));
+  String alcohol_concentration_str = "Alcohol Concentration: " + String(alcohol_concentration) + " mg/L";
+  Serial.println(alcohol_concentration_str);
+  lcd.clear();
+  lcd.print(String(alcohol_concentration) + " mg/L");
+  SerialBT.println(alcohol_concentration_str);
+  digitalWrite(BUZZER_PIN, LOW);
+}
+float calculateAlcoholConcentration(float ratio) {
+  float m = 45;
+  float b = -0.77;
+  double alcohol_ppm = (log10(ratio) - b) / m ;
+  double alcohol_mg_per_l = alcohol_ppm * 1.25;
+  return alcohol_mg_per_l;
+}
+</code>
 ===== Mod de functionare =====