/*
  Project: Physical Computing
  Circuit: Potentiometer-LED
  Boards Supported: UNO R3/R4, Nano, ESP32
  Function: Reads a varying voltage from a potentiometer and controls the brightness of an LED.
  
  Author: STEMVentor Educonsulting
  
  This code is copyrighted. Please do not reuse or share for any purpose other than for learning with subscribed STEMVentor programs. This code is for educational purposes only and is not for production use.
*/
 
// LIBRARIES
 
// PIN DEFINTIONS
#LED_PIN 3 // Must be a PWM pin
#POTENTIOMETER_PIN A0
 
// CONSTANT DEFINITIONS
 
// GLOBAL VARIABLES
uint8_t potentiometer_value;
uint8_t brightness;
 
// INITIALIZE OBJECTS
 
// LOCAL FUNCTIONS
void ledSetup()
{
  // Set the LED pin mode to output.
  pinMode(LED_PIN, OUTPUT);
  digitalWrite(LED_PIN, LOW);
}
 
void potentiometerSetup()
{
  // initialize the Potentiometer pin as an input.
  pinMode(POTENTIOMETER_PIN, INPUT);
}
 
void readPotentiometer()
{
  // Read the value of the Potentiometer state.
  potentiometer_value = analogRead(POTENTIOMETER_PIN);
  Serial.print("Potentiometer value: ");
  Serial.println(potentiometer_value);
  
  // For Arduino Nano
  // analogRead returns a number between 0 and 1024 while analogWrite takes a number between 0-255
  // Use the map function to do the proportional conversion.
  brightness = map(potentiometer_value, 0, 1024, 0, 255); 
 
  // For ESP32 
  // analogRead returns a number between 0 and 4098
  // brightness = map(potentiometerValue, 0, 4098, 0, 255);
  
  Serial.print("Brightness value: ");
  Serial.println(brightness);
}
 
void analogWriteLed(int value)
{
  analogWrite(LED_PIN, value);
}
 
// THE setup FUNCTION RUNS ONCE WHEN YOU PRESS RESET OR POWER THE BOARD.
void setup() 
{
  // Start the serial communication with baud rate suitable for your components.
  Serial.begin(9600);
  ledSetup();
  potentiometerSetup();
  Serial.println("The board is ready!");
}
 
// THE loop FUNCTION RUNS OVER AND OVER AGAIN FOREVER UNTIL THE BOARD IS POWERED OFF.
void loop() 
{
  readPotentiometer();
  analogWriteLed(brightness);
  delay(1000);
}