> For the complete documentation index, see [llms.txt](https://longer-vision-robot.gitbook.io/arduino-full-stack/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://longer-vision-robot.gitbook.io/arduino-full-stack/03_led_sensors/024_led_lightcup.md).

# 3.6 LED Light Cup

## Hardware Wiring

![LED Light Cup](/files/-LCFEAJofLnDoNVIieCO)

## Sketch

The code can be found at [Examples\_Arduino - sensor-kit-for-arduino - \_024\_LED\_LightCup - \_024\_LED\_LightCup.ino](https://github.com/LongerVisionRobot/Examples_Arduino/blob/master/sensor-kit-for-arduino/_024_LED_LightCup/_024_LED_LightCup.ino).

```
int LedPinA = 5;
int LedPinB = 6;
int ButtonPinA = 7;
int ButtonPinB = 4;
int buttonStateA = 0; 
int buttonStateB = 0;
int brightness   = 0;

void setup() 
{
    pinMode(LedPinA, OUTPUT); 
    pinMode(LedPinB, OUTPUT);  
    pinMode(ButtonPinA, INPUT); 
    pinMode(ButtonPinB, INPUT);     
}

void loop() 
{
  buttonStateA = digitalRead(ButtonPinA);
  if (buttonStateA == HIGH && brightness != 255)
  { 
   brightness ++;
  } 

   buttonStateB = digitalRead(ButtonPinB);
   if (buttonStateB == HIGH && brightness != 0)
  { 
   brightness --;
  } 
    analogWrite(LedPinA, brightness);        // A turns dark slowly
    analogWrite(LedPinB, 255 - brightness);  // B turns bright slowly
    delay(25);
}
```