In this Pong Game project, The dot matrix that we’re going to use in this guide is a 8×8 matrix which means that it has 8 columns and 8 rows, so it contains a total of 64 LEDs.
The MAX7219 chip makes it easier to control the dot matrix, by just using 3 digital pins of the Arduino board. You can control more than one matrix at a time. For that you just need to connect them to each other, as they have pins in both sides to extend the dot matrix.
Circuit Diagram
Components Required
8×8 Dot Matrix with MAX7219 - 1
Arduino UNO
Potentiometer 10K ohms
Jumper Wires
Installing the Arduino_Library
Download timer Libray
Download Led Control library
Subscribe and Download code.
In your Arduino IDE, to install the libraries go to Sketch > Include Library > Add .ZIP library… and select the library you’ve just downloaded.
After installing the required libraries, copy the following code to your Arduino IDE.
Subscribe and Download code.
Arduino Code
#include "LedControl.h"
#include "Timer.h"
#define POTPIN A5 // Potentiometer
#define PADSIZE 3
#define BALL_DELAY 200
#define GAME_DELAY 10
#define BOUNCE_VERTICAL 1
#define BOUNCE_HORIZONTAL -1
#define NEW_GAME_ANIMATION_SPEED 50
#define HIT_NONE 0
#define HIT_CENTER 1
#define HIT_LEFT 2
#define HIT_RIGHT 3
//#define DEBUG 1
byte sad[] = {
B00000000,
B01000100,
B00010000,
B00010000,
B00000000,
B00111000,
B01000100,
B00000000
};
byte smile[] = {
B00000000,
B01000100,
B00010000,
B00010000,
B00010000,
B01000100,
B00111000,
B00000000
};
Timer timer;
LedControl lc = LedControl(12,11,10,1);
byte direction; // Wind rose, 0 is north
int xball;
int yball;
int yball_prev;
byte xpad;
int ball_timer;
void setSprite(byte *sprite){
for(int r = 0; r < 8; r++){
lc.setRow(0, r, sprite[r]);
}
}
void newGame() {
lc.clearDisplay(0);
// initial position
xball = random(1, 7);
yball = 1;
direction = random(3, 6); // Go south
for(int r = 0; r < 8; r++){
for(int c = 0; c < 8; c++){
lc.setLed(0, r, c, HIGH);
delay(NEW_GAME_ANIMATION_SPEED);
}
}
setSprite(smile);
delay(1500);
lc.clearDisplay(0);
}
void setPad() {
xpad = map(analogRead(POTPIN), 0, 1020, 8 - PADSIZE, 0);
}
void debug(const char* desc){
#ifdef DEBUG
Serial.print(desc);
Serial.print(" XY: ");
Serial.print(xball);
Serial.print(", ");
Serial.print(yball);
Serial.print(" XPAD: ");
Serial.print(xpad);
Serial.print(" DIR: ");
Serial.println(direction);
}
int checkBounce() {
if(!xball || !yball || xball == 7 || yball == 6){
int bounce = (yball == 0 || yball == 6) ? BOUNCE_HORIZONTAL : BOUNCE_VERTICAL;
#ifdef DEBUG
debug(bounce == BOUNCE_HORIZONTAL ? "HORIZONTAL" : "VERTICAL");
return bounce;
}
return 0;
}
int getHit() {
if(yball != 6 || xball < xpad || xball > xpad + PADSIZE){
return HIT_NONE;
}
if(xball == xpad + PADSIZE / 2){
return HIT_CENTER;
}
return xball < xpad + PADSIZE / 2 ? HIT_LEFT : HIT_RIGHT;
}
bool checkLoose() {
return yball == 6 && getHit() == HIT_NONE;
}
void moveBall() {
debug("MOVE");
int bounce = checkBounce();
if(bounce) {
switch(direction){
case 0:
direction = 4;
break;
case 1:
direction = (bounce == BOUNCE_VERTICAL) ? 7 : 3;
break;
case 2:
direction = 6;
break;
case 6:
direction = 2;
break;
case 7:
direction = (bounce == BOUNCE_VERTICAL) ? 1 : 5;
break;
case 5:
direction = (bounce == BOUNCE_VERTICAL) ? 3 : 7;
break;
case 3:
direction = (bounce == BOUNCE_VERTICAL) ? 5 : 1;
break;
case 4:
direction = 0;
break;
}
debug("->");
}
// Check hit: modify direction is left or right
switch(getHit()){
case HIT_LEFT:
if(direction == 0){
direction = 7;
} else if (direction == 1){
direction = 0;
}
break;
case HIT_RIGHT:
if(direction == 0){
direction = 1;
} else if(direction == 7){
direction = 0;
}
break;
}
// Check orthogonal directions and borders ...
if((direction == 0 && xball == 0) || (direction == 4 && xball == 7)){
direction++;
}
if(direction == 0 && xball == 7){
direction = 7;
}
if(direction == 4 && xball == 0){
direction = 3;
}
if(direction == 2 && yball == 0){
direction = 3;
}
if(direction == 2 && yball == 6){
direction = 1;
}
if(direction == 6 && yball == 0){
direction = 5;
}
if(direction == 6 && yball == 6){
direction = 7;
}
// "Corner" case
if(xball == 0 && yball == 0){
direction = 3;
}
if(xball == 0 && yball == 6){
direction = 1;
}
if(xball == 7 && yball == 6){
direction = 7;
}
if(xball == 7 && yball == 0){
direction = 5;
}
yball_prev = yball;
if(2 < direction && direction < 6) {
yball++;
} else if(direction != 6 && direction != 2) {
yball--;
}
if(0 < direction && direction < 4) {
xball++;
} else if(direction != 0 && direction != 4) {
xball--;
}
xball = max(0, min(7, xball));
yball = max(0, min(6, yball));
debug("AFTER MOVE");
}
void gameOver() {
setSprite(sad);
delay(1500);
lc.clearDisplay(0);
}
void drawGame() {
if(yball_prev != yball){
lc.setRow(0, yball_prev, 0);
}
lc.setRow(0, yball, byte(1 << (xball)));
byte padmap = byte(0xFF >> (8 - PADSIZE) << xpad) ;
#ifdef DEBUG
//Serial.println(padmap, BIN);
lc.setRow(0, 7, padmap);
}
void setup() {
// The MAX72XX is in power-saving mode on startup,
// we have to do a wakeup call
pinMode(POTPIN, INPUT);
lc.shutdown(0,false);
// Set the brightness to a medium values
lc.setIntensity(0, 8);
// and clear the display
lc.clearDisplay(0);
randomSeed(analogRead(0));
#ifdef DEBUG
Serial.begin(9600);
Serial.println("Pong");
newGame();
ball_timer = timer.every(BALL_DELAY, moveBall);
}
void loop() {
timer.update();
// Move pad
setPad();
#ifdef DEBUG
Serial.println(xpad);
// Update screen
drawGame();
if(checkLoose()) {
debug("LOOSE");
gameOver();
newGame();
}
delay(GAME_DELAY);
}
Result
Here’s the final demonstration of me playing the pong game. Have fun!