Alessandro Pasotti<\/a>.<\/p>\nFor the pong game, you just need to add a 1k ohm potentiometer to the previous schematic. Assemble the new circuit\u00a0as shown below:<\/p>\n
![\"pongping_bb\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/07\/pongping_bb.jpg?resize=700%2C544&quality=100&strip=all&ssl=1\")
<\/p>\n
Code<\/h2>\n
Then, upload the following code to your Arduino board:<\/p>\n
\/* \n * Play pong on an 8x8 matrix - project from itopen.it\n *\/\n \n#include "LedControl.h"\n#include "Timer.h"\n \n#define POTPIN A5 \/\/ Potentiometer\n#define PADSIZE 3\n#define BALL_DELAY 200\n#define GAME_DELAY 10\n#define BOUNCE_VERTICAL 1\n#define BOUNCE_HORIZONTAL -1\n#define NEW_GAME_ANIMATION_SPEED 50\n#define HIT_NONE 0\n#define HIT_CENTER 1\n#define HIT_LEFT 2\n#define HIT_RIGHT 3\n \n\/\/#define DEBUG 1\n \nbyte sad[] = {\nB00000000,\nB01000100,\nB00010000,\nB00010000,\nB00000000,\nB00111000,\nB01000100,\nB00000000\n};\n \nbyte smile[] = {\nB00000000,\nB01000100,\nB00010000,\nB00010000,\nB00010000,\nB01000100,\nB00111000,\nB00000000\n};\n \nTimer timer;\n \nLedControl lc = LedControl(12,11,10,1);\n \nbyte direction; \/\/ Wind rose, 0 is north\nint xball;\nint yball;\nint yball_prev;\nbyte xpad;\nint ball_timer;\n \nvoid setSprite(byte *sprite){\n for(int r = 0; r < 8; r++){\n lc.setRow(0, r, sprite[r]);\n }\n}\n \nvoid newGame() {\n lc.clearDisplay(0);\n \/\/ initial position\n xball = random(1, 7);\n yball = 1;\n direction = random(3, 6); \/\/ Go south\n for(int r = 0; r < 8; r++){\n for(int c = 0; c < 8; c++){\n lc.setLed(0, r, c, HIGH);\n delay(NEW_GAME_ANIMATION_SPEED);\n }\n }\n setSprite(smile);\n delay(1500);\n lc.clearDisplay(0);\n}\n \nvoid setPad() {\n xpad = map(analogRead(POTPIN), 0, 1020, 8 - PADSIZE, 0);\n}\n \nvoid debug(const char* desc){\n#ifdef DEBUG\n Serial.print(desc);\n Serial.print(" XY: ");\n Serial.print(xball);\n Serial.print(", ");\n Serial.print(yball);\n Serial.print(" XPAD: ");\n Serial.print(xpad);\n Serial.print(" DIR: ");\n Serial.println(direction);\n#endif\n}\n \nint checkBounce() {\n if(!xball || !yball || xball == 7 || yball == 6){\n int bounce = (yball == 0 || yball == 6) ? BOUNCE_HORIZONTAL : BOUNCE_VERTICAL;\n#ifdef DEBUG\n debug(bounce == BOUNCE_HORIZONTAL ? "HORIZONTAL" : "VERTICAL");\n#endif\n return bounce;\n }\n return 0;\n}\n \nint getHit() {\n if(yball != 6 || xball < xpad || xball > xpad + PADSIZE){\n return HIT_NONE;\n }\n if(xball == xpad + PADSIZE \/ 2){\n return HIT_CENTER;\n }\n return xball < xpad + PADSIZE \/ 2 ? HIT_LEFT : HIT_RIGHT;\n}\n \nbool checkLoose() {\n return yball == 6 && getHit() == HIT_NONE;\n}\n \nvoid moveBall() {\n debug("MOVE");\n int bounce = checkBounce();\n if(bounce) {\n switch(direction){\n case 0:\n direction = 4;\n break;\n case 1:\n direction = (bounce == BOUNCE_VERTICAL) ? 7 : 3;\n break;\n case 2:\n direction = 6;\n break;\n case 6:\n direction = 2;\n break;\n case 7:\n direction = (bounce == BOUNCE_VERTICAL) ? 1 : 5;\n break;\n case 5:\n direction = (bounce == BOUNCE_VERTICAL) ? 3 : 7;\n break;\n case 3:\n direction = (bounce == BOUNCE_VERTICAL) ? 5 : 1;\n break;\n case 4:\n direction = 0;\n break;\n }\n debug("->");\n }\n \n \/\/ Check hit: modify direction is left or right\n switch(getHit()){\n case HIT_LEFT:\n if(direction == 0){\n direction = 7;\n } else if (direction == 1){\n direction = 0;\n }\n break;\n case HIT_RIGHT:\n if(direction == 0){\n direction = 1;\n } else if(direction == 7){\n direction = 0;\n }\n break;\n }\n \n \/\/ Check orthogonal directions and borders ...\n if((direction == 0 && xball == 0) || (direction == 4 && xball == 7)){\n direction++;\n }\n if(direction == 0 && xball == 7){\n direction = 7;\n }\n if(direction == 4 && xball == 0){\n direction = 3;\n }\n if(direction == 2 && yball == 0){\n direction = 3;\n }\n if(direction == 2 && yball == 6){\n direction = 1;\n }\n if(direction == 6 && yball == 0){\n direction = 5;\n }\n if(direction == 6 && yball == 6){\n direction = 7;\n }\n \n \/\/ "Corner" case\n if(xball == 0 && yball == 0){\n direction = 3;\n }\n if(xball == 0 && yball == 6){\n direction = 1;\n }\n if(xball == 7 && yball == 6){\n direction = 7;\n }\n if(xball == 7 && yball == 0){\n direction = 5;\n }\n \n yball_prev = yball;\n if(2 < direction && direction < 6) {\n yball++;\n } else if(direction != 6 && direction != 2) {\n yball--;\n }\n if(0 < direction && direction < 4) {\n xball++;\n } else if(direction != 0 && direction != 4) {\n xball--;\n }\n xball = max(0, min(7, xball));\n yball = max(0, min(6, yball));\n debug("AFTER MOVE");\n}\n \nvoid gameOver() {\n setSprite(sad);\n delay(1500);\n lc.clearDisplay(0);\n}\n \nvoid drawGame() {\n if(yball_prev != yball){\n lc.setRow(0, yball_prev, 0);\n }\n lc.setRow(0, yball, byte(1 << (xball)));\n byte padmap = byte(0xFF >> (8 - PADSIZE) << xpad) ;\n#ifdef DEBUG\n \/\/Serial.println(padmap, BIN);\n#endif\n lc.setRow(0, 7, padmap);\n}\n \nvoid setup() {\n \/\/ The MAX72XX is in power-saving mode on startup,\n \/\/ we have to do a wakeup call\n pinMode(POTPIN, INPUT);\n \n lc.shutdown(0,false);\n \/\/ Set the brightness to a medium values\n lc.setIntensity(0, 8);\n \/\/ and clear the display\n lc.clearDisplay(0);\n randomSeed(analogRead(0));\n#ifdef DEBUG\n Serial.begin(9600);\n Serial.println("Pong");\n#endif\n newGame();\n ball_timer = timer.every(BALL_DELAY, moveBall);\n}\n \nvoid loop() {\n timer.update();\n \/\/ Move pad\n setPad();\n#ifdef DEBUG\n Serial.println(xpad);\n#endif\n \/\/ Update screen\n drawGame();\n if(checkLoose()) {\n debug("LOOSE");\n gameOver();\n newGame();\n }\n delay(GAME_DELAY);\n}\n<\/code><\/pre>\n\tView raw code<\/a><\/p>\nDemonstration<\/h2>\n
Here’s the final demonstration of me playing the pong game. Have fun!<\/p>\n
![\"gif_game_f\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/07\/gif_game_f.gif?resize=480%2C270&quality=100&strip=all&ssl=1\")
<\/p>\n
Wrapping up<\/h2>\n
Have you ever used the dot matrix in your Arduino Projects?<\/p>\n
Let me know by leaving a comment below.<\/p>\n
If you like this post probably you might like my next ones (click here to subscribe my blog<\/a>). Thanks for reading,<\/p>\nRui<\/p>\n","protected":false},"excerpt":{"rendered":"
The dot matrix that we\u2019re going to use in this\u00a0guide is a 8×8 matrix which means that it has 8 columns and 8 rows, so it contains a total of … <\/p>\n
CONTINUE READING \u00bb<\/a><\/p>\n","protected":false},"author":1,"featured_media":24518,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[267,2,302,269,264,10],"tags":[],"class_list":["post-24473","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-arduino-project","category-arduino","category-0-guide","category-guide-project","category-project","category-a-tutorials"],"aioseo_notices":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/07\/featured-image-1.jpg?fit=850%2C482&quality=100&strip=all&ssl=1","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/posts\/24473","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/comments?post=24473"}],"version-history":[{"count":0,"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/posts\/24473\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/media\/24518"}],"wp:attachment":[{"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/media?parent=24473"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/categories?post=24473"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/randomnerdtutorials.com\/wp-json\/wp\/v2\/tags?post=24473"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/07\/featured-image-1.jpg?resize=700%2C397&quality=100&strip=all&ssl=1\")
<\/p>\n![\"dotmatrixphoto\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/07\/dotmatrixphoto.jpg?resize=900%2C367&quality=100&strip=all&ssl=1\")
<\/p>\n![](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/10\/header-200.png?w=1200&quality=100&strip=all&ssl=1\")
<\/a><\/p>\n![\"index\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/07\/index.jpg?resize=471%2C487&quality=100&strip=all&ssl=1\")
<\/p>\n![\"faces\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/07\/faces.jpg?resize=567%2C454&quality=100&strip=all&ssl=1\")
<\/p>\n![\"gif_face_final\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2016\/07\/gif_face_final.gif?resize=480%2C270&quality=100&strip=all&ssl=1\")
<\/p>\n