// X-Pong by Hari Wiguna, 2015 // Original idea by Don Lamb // Arduino Pins int btnLeft = 13; int btnRight = 4; int led0 = 5; int led7 = led0 + 7; // Game variables int ballPosition = 0; int ballDirection = 0; int prevBallPosition = 0; int ballDelay = 100; int debounceDelay = 200; // Make code easier to read int IsPressed = LOW; void setup() { Serial.begin(9600); pinMode(btnLeft, INPUT_PULLUP); pinMode(btnRight, INPUT_PULLUP); for (int x = 0; x <= 7; x++) pinMode(led0 + x, OUTPUT); } void loop() { if (ballDirection == 0) WaitForServe(); else { DrawBall(); DelayBall(); if ((ballPosition == 0) && (ballDirection == -1)) WaitForPlayer(btnLeft, +1, 0); if ((ballPosition == 7) && (ballDirection == +1)) WaitForPlayer(btnRight, -1, 7); else { MoveBall(); } } } void DelayBall() { unsigned long timeout = millis() + ballDelay; while (millis() < timeout) { if ((ballPosition != 0 ) && (digitalRead(btnLeft) == IsPressed)) { GameOver(0); break; } if ((ballPosition != 7) && (digitalRead(btnRight) == IsPressed)) { GameOver(7); break; } } } void WaitForServe() { while (true) { if (digitalRead(btnLeft) == IsPressed) { ballPosition = 0; ballDirection = +1; break; } if (digitalRead(btnRight) == IsPressed) { ballPosition = 7; ballDirection = -1; break; } } delay(200); } void SetLED(int which, int state) { int pin = led7 - which; if (pin >= led0 && pin <= led7) digitalWrite(pin, state); } void GameOver(int which) { for (int n = 0; n < 4; n++) { SetLED(which, HIGH); delay(100); SetLED(which, LOW); delay(100); } ballDirection = 0; ballDelay = 200; } void MoveBall() { prevBallPosition = ballPosition; ballPosition = ballPosition + ballDirection; } void DrawBall() { SetLED(prevBallPosition, LOW); SetLED(ballPosition, HIGH); } void WaitForPlayer(int buttonPin, int ballDir, int gameOverPin) { ballDirection = 0; unsigned long timeout = millis() + 1000L; while (millis() < timeout) { if (digitalRead(buttonPin) == IsPressed) { delay(debounceDelay); // allow button to flutter ballDirection = ballDir; ballDelay = ballDelay - 5; break; } } if (ballDirection == 0) GameOver(gameOverPin); }