#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <DHT.h>
// ---------------- OLED CONFIG ----------------
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define OLED_ADDR 0x3C
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
// ---------------- DHT CONFIG ----------------
#define DHTPIN 14 // GPIO 14
#define DHTTYPE DHT22 // DHT22 (AM2302)
DHT dht(DHTPIN, DHTTYPE);
// ---------------- SETUP ----------------
void setup() {
Serial.begin(115200);
// I2C pins for ESP32
Wire.begin(21, 22); // SDA, SCL
dht.begin();
if (!display.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR)) {
Serial.println("SSD1306 allocation failed");
while (true);
}
display.clearDisplay();
display.setTextSize(1);
display.setTextColor(WHITE);
display.setCursor(0, 0);
display.println("ESP32 + DHT22");
display.println("Initializing...");
display.display();
delay(2000);
}
// ---------------- LOOP ----------------
void loop() {
float humidity = dht.readHumidity();
float temperature = dht.readTemperature(); // Celsius
if (isnan(humidity) || isnan(temperature)) {
Serial.println("Failed to read from DHT sensor!");
return;
}
// Serial Monitor Output
Serial.print("Temperature: ");
Serial.print(temperature);
Serial.print(" °C | Humidity: ");
Serial.print(humidity);
Serial.println(" %");
// OLED Display Output
display.clearDisplay();
display.setCursor(0, 0);
display.setTextSize(1);
display.println("DHT22 Readings");
display.setTextSize(2);
display.setCursor(0, 18);
display.print(temperature);
display.println(" C");
display.setCursor(0, 42);
display.print(humidity);
display.println(" %");
display.display();
delay(2000);
}