Circuit Documentation

Summary

This circuit involves an Arduino UNO microcontroller interfaced with a DHT22 temperature and humidity sensor. The Arduino UNO reads data from the DHT22 sensor and outputs the temperature and humidity readings to the Serial Monitor.

Component List

DHT22

• Description: Temperature and Humidity Sensor
• Pins:
  • +: Power supply (3.3V or 5V)
  • Out: Data output
  • -: Ground

Arduino UNO

• Description: Microcontroller Board
• Pins:
  • UNUSED
  • IOREF
  • Reset
  • 3.3V
  • 5V
  • GND
  • Vin
  • A0 to A5
  • SCL
  • SDA
  • AREF
  • D13 to D0

ESP32 (30 pin)

• Description: Microcontroller Board (Not used in this circuit)
• Pins:
  • EN
  • VP
  • VN
  • D34 to D0
  • GND
  • Vin
  • 3V3

Wiring Details

DHT22

• + pin connected to a power supply (3.3V or 5V)
• Out pin connected to D2 pin of the Arduino UNO
• - pin connected to GND pin of the Arduino UNO

Arduino UNO

• GND pin connected to - pin of the DHT22
• D2 pin connected to Out pin of the DHT22

Documented Code

#include "DHT.h"  // Include the DHT library

#define DHTPIN 2      // GPIO pin connected to the DHT22 data pin
#define DHTTYPE DHT22 // Specify the sensor type (DHT11, DHT22, etc.)

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(115200); // Initialize serial communication
  dht.begin();          // Initialize the DHT sensor
  Serial.println("DHT22 Sensor Test");
}

void loop() {
  // Read temperature as Celsius
  float temperature = dht.readTemperature();
  // Read humidity
  float humidity = dht.readHumidity();

  // Check if any reading failed
  if (isnan(temperature) || isnan(humidity)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  // Print the results to the Serial Monitor
  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.println(" °C");

  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.println(" %");

  delay(50000); // Wait for 2 seconds before reading again
}

This code initializes the DHT22 sensor and reads temperature and humidity data from it. The readings are then printed to the Serial Monitor. If the sensor fails to provide readings, an error message is displayed.