// Nayla Januarisa Prihadi - J0404241149
#include <WiFi.h>
#include <HTTPClient.h>
#include "DHTesp.h"
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
// =====================
// OLED SETUP
// =====================
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
// =====================
// WIFI
// =====================
const char* ssid = "Wokwi-GUEST";
const char* password = "";
// =====================
// THINGSPEAK
// =====================
String writeApiKey = "770ZS1O8JYHNM1UR";
String serverUrl = "https://api.thingspeak.com/update";
// =====================
// PIN
// =====================
#define DHT_PIN 15
#define LED_PIN 2
DHTesp dht;
// Interval aman Wokwi
unsigned long lastSend = 0;
const unsigned long SEND_INTERVAL_MS = 30000;
void setup() {
Serial.begin(115200);
pinMode(LED_PIN, OUTPUT);
digitalWrite(LED_PIN, LOW);
dht.setup(DHT_PIN, DHTesp::DHT22);
// OLED init
Wire.begin(21, 22);
display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
display.clearDisplay();
display.setTextSize(1);
display.setTextColor(SSD1306_WHITE);
display.setCursor(0,0);
display.println("ESP32 DHT22");
display.println("Connecting WiFi");
display.display();
// WiFi
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(300);
}
display.println("WiFi OK");
display.display();
}
void loop() {
if (millis() - lastSend < SEND_INTERVAL_MS) return;
lastSend = millis();
TempAndHumidity data = dht.getTempAndHumidity();
if (isnan(data.temperature) || isnan(data.humidity)) {
display.clearDisplay();
display.setCursor(0,0);
display.println("DHT ERROR");
display.display();
return;
}
// URL ThingSpeak
String url = serverUrl +
"?api_key=" + writeApiKey +
"&field1=" + String(data.temperature, 2) +
"&field2=" + String(data.humidity, 2);
HTTPClient http;
http.begin(url);
int code = http.GET();
String payload = http.getString();
http.end();
bool success = payload.toInt() > 0;
if (success) {
digitalWrite(LED_PIN, HIGH);
delay(200);
digitalWrite(LED_PIN, LOW);
}
// OLED tampilkan status
display.clearDisplay();
display.setCursor(0,0);
display.printf("Temp : %.2f C\n", data.temperature);
display.printf("Hum : %.2f %%\n", data.humidity);
display.println("WiFi : OK");
display.print("Send : ");
display.println(success ? "SUCCESS" : "FAILED");
display.display();
}