Basic Arduino (serial.read)

/* Get input and turn the LED on and off */

const int LED = 10;

void setup(){
  Serial.begin(115200);
  pinMode(LED, OUTPUT);
}

void loop(){
  if(Serial.available()){
    char userInput = Serial.read();

    switch(userInput){
      case 'n':
      digitalWrite(LED, HIGH);
      break;

      case 'f':
      digitalWrite(LED, LOW);
      break;

      default:
      break;
    }
  }
}

// Adjust the LED brightness

const int LED = 10;

void setup(){
  Serial.begin(115200);
}

void loop(){
  if (Serial.available()){
    char userInput = Serial.read();

    switch(userInput){
      case '0': analogWrite(LED, 0); break;
      case '1': analogWrite(LED, 25 * 1); break;
      case '2': analogWrite(LED, 25 * 2); break;
      case '3': analogWrite(LED, 25 * 3); break;
      case '4': analogWrite(LED, 25 * 4); break;
      case '5': analogWrite(LED, 25 * 5); break;
      case '6': analogWrite(LED, 25 * 6); break;
      case '7': analogWrite(LED, 25 * 7); break;
      case '8': analogWrite(LED, 25 * 8); break;
      case '9': analogWrite(LED, 25 * 9); break;

      default: break;
    }
  }
}

const int digitalPin = 2;

void setup(){
  Serial.begin(115200);

  pinMode(digitalPin, INPUT);
}

void loop(){
  int digitalValue = digitalRead(digitalPin);
  Serial.println(digitalValue);
}

// from 2 to 5v = Print on the Serialmonitor (1) 
// from 2 to gnd = Print on the Serialmonitor (0)

const int digitalPin = 2;

void setup(){
  Serial.begin(115200);

  pinMode(digitalPin, INPUT);
}

void loop(){
  int digitalValue = digitalRead(digitalPin);
  Serial.println(digitalValue);
}


// print '0' on the SerialMonitor
// if push button Changing ouput value '1'

const int ledPin = 13;
const int buttonPin = 2;

void setup(){
  pinMode(ledPin, OUTPUT);
  pinMode(buttonPin, INPUT);
}

void loop(){
  int buttonInput = digitalRead(buttonPin);
  digitalWrite(ledPin, buttonInput);
}

// Turn on the LED when push Button

// faint bright depends on push the button

const int ledPin = 10;
const int buttonPin = 2;

void setup(){
  pinMode(ledPin, OUTPUT);
  pinMode(buttonPin, INPUT);
}

void loop(){
  int buttonInput = digitalRead(buttonPin);
  if(buttonInput == HIGH)
  {
    for(int t_high=0; t_high<=255; t_high++)
    {
      analogWrite(ledPin, t_high);
      delay(4);
    }
  }else {
    analogWrite(ledPin, 0);
  }
}

/* Make the LED Dice */

const int led[6] = { 3, 5, 6, 9, 10, 11 };
const int buttonPin = 2;

void setup()
{
  for(int x=0;x<=5;x++)
  {
    pinMode(led[x], OUTPUT);
  }
  pinMode(buttonPin, INPUT);
}

void loop() 
{
  int buttonInput = digitalRead(buttonPin);
  if(buttonInput == HIGH) 
  { 
    for(int x=0;x<=5;x++) 
    {  
      for(int x=0;x<=5;x++) 
      {
        digitalWrite(led[x], LOW);
      }

      digitalWrite(led[x], HIGH);
      buttonInput = digitalRead(buttonPin);
      if(buttonInput == LOW) break;

      delay(50);
      }
    }
 }