#include <driver/adc.h>
#include <driver/ledc.h>

#define acd 33            
#define pin 5            
#define f 50000       
#define r 10
int a;
float v;

void setup() {
  adc1_config_width(ADC_WIDTH_BIT_10); 
  adc1_config_channel_atten(ADC1_CHANNEL_5, ADC_ATTEN_DB_0); 
  ledcSetup(0, f, r);
  ledcAttachPin(pin, 0);

  Serial.begin(115200);
}

void loop() {
  a = map(analogRead(acd), 0, 4095, 0, 255); 
  ledcWrite(0, a);
  v = (a / 255.0) * 3.3;
  Serial.print("Voltage:");
  Serial.print(v); 
  Serial.println("v");

}