Paper prototypes:

Red LED flashlight:

 

LED streetlight

 

LED Wallet Light

 

LED / Photodiode IR transceiver

 

Device with LED notification on side

 

LED Pong

 

LED Bike Spoke Persistence of Vision Display

 

Desktop 3d POV display

 

LED-lit projector

 

 

Cup that lights up upon needing refill (checks force sensor for 1/3 full state)

 

Project - Pong on a LED matrix display

 

I implemented a working single player variant of Pong on a LED matrix display

This involved soldering 35 LEDs into a 7x5 matrix.

I wired the 7 columns to port B and the ground lines for each row to pins on ports C and D 

I used code to turn on each row in sequence, while changing the column bits each time.  I had a software framebuffer and updated the paddle/ball position every 100ms.

 

Initial testing (Space Invader!)

 

 

 

/*

  Pong v. 0.01

  Sam D'Amico

  EE47 Lab 2

 */

 

#define WIDTH 7

#define HEIGHT 5

 

// The setup() method runs once, when the sketch starts

 

void setup()   {                

  // initialize the LED pin as an output:

  pinMode(21, INPUT);

  pinMode(20, INPUT);  

  pinMode(19, INPUT);  

  DDRB = 0xFF;

  DDRD = 0xFF;

  DDRC = 0xFF;

  //DDRF = 0x00;

  // initialize the button pin as an input

  //pinMode(buttonPin, INPUT);

}

 

char display[HEIGHT][WIDTH] = {{0,0,0,0,0,0,0},

                               {0,0,0,0,0,0,0},

                               {0,0,0,0,0,0,0},

                               {0,0,0,0,0,0,0},

                               {0,0,0,0,0,0,0}};

 

char paddleX = 0, paddleY=0;

char ballX = 3, ballY = 3;

char ballVx = 1, ballVy = 1;

char lost = 0;

 

void movePaddle()

{

  static long now = 0;

  if((now+100) < millis())

  {

    display[paddleY][0] = 0;

    display[paddleY+1][0] = 0;

    if(paddleY > 0)

    {

      if(!digitalRead(21)) 

        paddleY--;

    } else paddleY = 0;

    if(paddleY < (HEIGHT-2))

    {

      if(!digitalRead(20))

        paddleY++;

    } else paddleY = 3;

    display[paddleY][0] = 1;

    display[paddleY+1][0] = 1;

    now = millis();

  }

}

 

void moveBall()

{

  static long now = 0;

  if((now+100) < millis())

  {

    display[ballY][ballX] = 0;

    ballX += ballVx;

    ballY += ballVy;

    if(ballX == (WIDTH-1)) ballVx*=-1;

    if(ballX == 0)

      if(ballY == paddleY || ballY == (paddleY+1)) ballVx*=-1;

      else {

        lost = 1;

        return;

      }

    if(ballY == (HEIGHT-1)) ballVy*=-1;

    if(ballY == 0) ballVy*=-1;

    display[ballY][ballX] = 1;

 

    now = millis();

  }

}

 

// the loop() method runs over and over again,

// as long as the Arduino has power

 

void loop()                     

{

  // Start with all LEDs off, but the first row on (D0 low)

  PORTB = 0x00;

  PORTD = 0b1111110;

  PORTC = 0xFF;

  // draw the contents of the framebuffer

  for(int i=0;i<HEIGHT;i++)

  {

    PORTB = 0x00;

    for(int j=0;j<WIDTH;j++)

    {

      // this could be faster if I just used one byte and sent it straight to the port, but array access is easy

      PORTB |= (display[i][j] << j);

    }

     // give time to render each row with basically no flicker

    delay(1);

    // since the row control is split between D0-3 and C6 (pin 9)

    if(i < HEIGHT-2)

      PORTD = ~(2 << i);

    else {

      PORTD = 0xFF;

      digitalWrite(9, LOW);

    }

  }

 

  // Reset the game if you press the start button after losing

  if(!digitalRead(19))

  {

   lost = 0; 

   ballX = 3;

   ballY = 3;

   ballVx = 1;

   ballVy = 1;

   //delay(10000);

 }

 

  // Move the ball and paddle otherwise

  if(!lost)

  {

    moveBall();

    movePaddle();

  }

 

}