#include <OneWire.h> 
#include <DallasTemperature.h> 
 
// Define the pin connected to the DS18B20 sensor 
const int oneWireBus = 2; 
 
// Setup a OneWire instance and pass it to DallasTemperature 
OneWire oneWire(oneWireBus); 
DallasTemperature sensors(&oneWire); 
 
void setup() { 
    Serial.begin(115200); 
    sensors.begin();  // Initialize the DS18B20 sensor 
} 
 
void loop() { 
    sensors.requestTemperatures();  // Request temperature 
    float temperatureC = sensors.getTempCByIndex(0); 
     
    Serial.print("Temperature: "); 
    Serial.print(temperatureC); 
    Serial.println(" °C"); 
     
    delay(1000);  // Read temperature every second 
} 
#include <math.h>  // For the log() function 
 
const float BETA = 3950; // Beta coefficient of the thermistor 
const int analogPin = 34; // ESP32 ADC pin 
 
void setup() { 
  Serial.begin(115200);  // Start serial monitor at 115200 baud 
} 
 
void loop() { 
  // Read the analog value (0-4095 range for ESP32) 
  int analogValue = analogRead(analogPin); 
 
  // Temperature calculation (adjusted for ESP32 ADC range) 
  float celsius = 1 / (log(1 / (4095.0 / analogValue - 1)) / BETA 
+ 1.0 / 298.15) - 273.15; 
 
  // Output temperature to the serial monitor 
  Serial.print("Temperature: "); 
  Serial.print(celsius); 
  Serial.println(" ℃"); 
 
  delay(1000);  // Wait 1 second before reading again 
} 

// --- Configuration Constants ---
const int pwmPin = 13;
const int frequency = 5000;
const uint8_t resolution = 8; // 0-255 range
const uint32_t dutyCycle = 128; // ~50% for 8-bit
// ========================== SETUP ==========================
void setup() {
 Serial.begin(115200); // Optional: for debug messages
 Serial.println("ESP32 Fixed PWM Example (Pin-Based API)");
 // 1. Configure and attach the PWM pin using LEDC
 ledcAttach(pwmPin, frequency, resolution);
 Serial.printf("Attached PWM to GPIO %d\n", pwmPin);
 // 2. Set the fixed PWM duty cycle using ledcWrite with the PIN number
 ledcWrite(pwmPin, dutyCycle); // Using pwmPin here
 Serial.printf("Set fixed duty cycle %u on pin %d\n", dutyCycle,
pwmPin);
}
// ========================== LOOP ==========================
void loop() {
 // PWM is handled by hardware. Nothing needed here for fixed output.
 delay(1000);
}