Candyman pink

C Code

// *********************
// * Ball bouncing program
// * By: Scrooge'Mc'Cat himself
// * At: Sep 1st 2025 7:25 PM
// *
// * NOTE:
// * When first running this program you may experience
// * quite a long delay. This is completely expected due to
// * the inefficiency of my MCU simulator and compiler code.
// * The program's code itself is fine. Trust me.
// *********************

#include stdout.asm

byte strlen(string text) {
    // Create a copy because the compiler is broken (sorry)
    string cpy = text;

// Keep on incrementing cpy until a 0 is reached
    while (*cpy) {
      cpy = cpy + 1;
    }

// cpy is end of string, text is start, so length = end - start
    return cpy - text;
}

void main() {
  // Customizable features
  string ballText = "DVD"; // The text of the ball (I know, not really a ball...)
  string trailChar = " ";     // The trail the "ball" leaves behind (only first char is accounted for, set to space for no trail.

byte ballTextLen = strlen(ballText);

// Position of the ball
  byte x = 0;
  byte y = 0;

// Velocity of the ball (1 is 1, 2 is -1, other is at rest)
  byte vx = 1;
  byte vy = 1;

// The ball's previous position
  byte prevX = x;
  byte prevY = y;

// Someplace the program won't reach to store spaces (like an unsafe heap)
  word spaces = 32768;
  
  // Add spaces equal to the text
  byte i = 0;
  word ptr = spaces;  
  for (i = 0; i < ballTextLen; i = i + 1) {
    ptr = ptr + 1;
    *ptr = *trailChar;
  }

// Make sure it's null terminated
  ptr = ptr + 1;
  *ptr = 0;

while (1) { // Update loop
    // Update X-coordinate
    if (vx == 1)  { x =  x + 1; }
    if (vx == 2) { x = x - 1; }

// Update Y-coordinate
    if (vy == 1) { y = y + 1; }
    if (vy == 2) { y = y - 1; }

// Check for bounces, adjusting velocity accordingly
    if (y == 20) { vy = 2; }
    if (y == 0)   { vy = 1; }

if (x == 41) { vx = 2; }
    if (x == 0) { vx = 1; }

// Draw the ball
    moveCursor(x, y);
    print(ballText);

// Erase the previous render of the ball
    moveCursor(prevX, prevY);
    print(spaces);

// Update the previous position for the next "frame"
    prevX = x;
    prevY = y;
  }
}

Assembly

Memory

Output

Registers

General Purpose

AX: 0
BX: 0
CX: 0
DX: 0
EX: 0
FX: 0

FL

FL: 0

Instruction

IP: 0

Stack Pointer

SP: 0

Base Pointer

BP: 0