I am trying to make a pong program, but I am running into issues.

When I run this code, I get the paddles and the ball to output, but then there's white fuzz at the top of the screen, and nothing happens unless I hold down enter, then the ball moves very slowly. When the ball goes to the other side of the screen, the program stops.

Any ideas as to what is going on? I have the variables already set at the top of the program, so it's not the variables if that's what you're thinking.

I also have the project uploaded to GitHub if you want to try it out yourself, to troubleshoot better. https://github.com/Spyderdude2001/Pong

Thank you if you help out!

Code:
```void play(){     gfx_FillScreen(9);     gfx_Sprite(scoreErase,0,0);     ps(p1score,0,0);     gfx_Sprite(scoreErase,330,0);     ps(p2score,330,0);     do{         gfx_SetColor(gfx_white);         gfx_FillRectangle(ballx, bally, 4, 4);         gfx_FillRectangle(0,p1,5,20);         gfx_FillRectangle(316,p2,5,20);         delay(50);         if (ballx <= 6){             if (bally-3>=p1&&bally+3<=p1+19)                 yballdir = floor((p1-bally-8)/2);                 ballx = 6;             xballdir = 1;         }else{         score();         }         if (ballx >= 312){             if (bally-3>=p2&&bally+3<=p2+19)                 yballdir = floor((p2-bally-8)/2);                 ballx = 312;             xballdir = -1;         }else{         score();         }         if (bally<11 || bally>236)             yballdir = -yballdir;         ballx+=xballdir;         bally+=yballdir;         gfx_SetColor(gfx_black);         kb_Scan();         if (kb_Data == kb_7){             gfx_FillRectangle(0,p1,5,20);             p1-=5;         }         if (kb_Data == kb_1){             gfx_FillRectangle(0,p1,5,20);             p1+=5;         }         if (kb_Data == kb_3){             gfx_FillRectangle(316,p2,5,20);             p2+=5;         }         if (kb_Data == kb_9){             gfx_FillRectangle(316,p2,5,20);             p2-=5;         }         if (kb_Data == kb_Clear){             leave = 1;         }         if (p1<10)             p1=10;         if (p1>221)             p1 = 221;         if (p2<10);             p2=10;         if (p2>221)             p2 = 221;     }while(p1score<7 && p2score<7 || leave == 1);     ps("Press [CLEAR] for Main Menu",80,120);     ps("Press [ENTER] to Play Again",60,130);     delay(5000); }```
Well you didn't show the whole code and you are using global variables, so who knows.
Here is the entire code

Code:
```#include <stdbool.h> #include <stddef.h> #include <stdint.h> #include <tice.h> #include <math.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <keypadc.h> #include <graphx.h> #include "gfx/logo_gfx.h" void play(); void mainMenu(); void dispMainMenu(); void ps(); void score(); int setting = 0; uint8_t p1 = 10; uint8_t p2 = 10; uint8_t ballx = 7; uint8_t bally = 10; int xballdir = 1; int yballdir = 1; uint8_t p1score = 0; uint8_t p2score = 0; uint8_t leave = 0; uint8_t gmode = 1; uint8_t directionNum = 1; void main(void) {     uint8_t pick = 0;     gfx_Begin();     gfx_SetPalette(logo_gfx_pal, sizeof_logo_gfx_pal, 0);     dispMainMenu();     mainMenu();     gfx_End();     os_ClrHome(); } void mainMenu(){     uint8_t leave = 0;     while(leave==0){         kb_Scan();         if (kb_Data == kb_Clear)             leave=1;         if (kb_Data == kb_Enter)                 play();         }     } void play(){     gfx_FillScreen(9);     gfx_Sprite(scoreErase,0,0);     ps(p1score,0,0);     gfx_Sprite(scoreErase,330,0);     ps(p2score,330,0);     do{         gfx_SetColor(gfx_white);         gfx_FillRectangle(ballx, bally, 4, 4);         gfx_FillRectangle(0,p1,5,20);         gfx_FillRectangle(316,p2,5,20);         delay(50);         if (ballx <= 6){             if (bally-3>=p1&&bally+3<=p1+19)                 yballdir = floor((p1-bally-8)/2);                 ballx = 6;             xballdir = 1;         }else{         score();         }         if (ballx >= 312){             if (bally-3>=p2&&bally+3<=p2+19)                 yballdir = floor((p2-bally-8)/2);                 ballx = 312;             xballdir = -1;         }else{         score();         }         if (bally<11 || bally>236)             yballdir = -yballdir;         ballx+=xballdir;         bally+=yballdir;         gfx_SetColor(gfx_black);         kb_Scan();         if (kb_Data == kb_7){             gfx_FillRectangle(0,p1,5,20);             p1-=5;         }         if (kb_Data == kb_1){             gfx_FillRectangle(0,p1,5,20);             p1+=5;         }         if (kb_Data == kb_3){             gfx_FillRectangle(316,p2,5,20);             p2+=5;         }         if (kb_Data == kb_9){             gfx_FillRectangle(316,p2,5,20);             p2-=5;         }         if (kb_Data == kb_Clear){             leave = 1;         }         if (p1<10)             p1=10;         if (p1>221)             p1 = 221;         if (p2<10);             p2=10;         if (p2>221)             p2 = 221;     }while(p1score<7 && p2score<7 || leave == 1);     ps("Press [CLEAR] for Main Menu",80,120);     ps("Press [ENTER] to Play Again",60,130);     delay(5000); } void dispMainMenu(){     gfx_FillScreen(8);     ps("PONG",125,100);     ps("--------------",100,110);     ps("Press [CLEAR] to Exit",80,130);     ps("Press [ENTER] to Play",80,120);     ps("Press [MODE] for controls",75,140); } void ps(char *inputString, int8_t xValue, int8_t yValue){     gfx_PrintStringXY(inputString,xValue,yValue); } void score(){     uint8_t leave = 0;     if (ballx==6){         gfx_Sprite(scoreErase,0,0);         ps(p1score,0,0);     }     if (ballx==312){         gfx_Sprite(scoreErase,330,0);         ps(p2score,330,0);     }     while(leave == 0){         kb_Scan();         if (kb_Data == kb_Enter)             leave = 1;     }     gfx_SetColor (gfx_black);     gfx_FillRectangle (ballx, bally, 4, 4); } ```
B) not everything should be a global. You can pass values and structures of values between functions
Whats so bad about all my variables as global? And what do you mean by git? Is it the tracking software or something else?
Global variables have a number of issues. They can make it more difficult to debug a program and can be slower in some circumstances. In general, you only want to use globals for game state that persists between frames, and use local variables or function arguments for everything else.

Git is a version control system, and GitHub hosts Git repositories online - I've recently written a post about it. TL;DR, you shouldn't use GitHub as a generic file hosting service. If you want to share your code online with Git, use the commands in my post. If not, you might as well use a hosting service like Google Drive or Mediafire - none of the benefits of GitHub work if everything is in a zip file.
If you're only using a global variable locally, I think it becomes a waste of RAM. That's the only thing I had off the top of my head.

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