In this video, Commodore Tutorials introduces screen RAM coin collection through a clever C64 maze game example. As players collect coins, a counter in the top right corner increases. When every coin disappears from the maze, an exit door appears so the player can finish the stage. This format not only makes learning fun, but also helps viewers connect game logic with on-screen action.
Understanding Character Graphics and Screen RAM
At the start, Commodore Tutorials reminds viewers that the C64’s screen is always a 40 by 25 character grid, regardless of the graphics. Each object, including every coin, is just a character in the set. When a player picks up a coin, the code replaces that coin’s screen code with a blank character, immediately making the coin vanish. Because every action relies on this grid, keeping track of screen RAM becomes second nature for effective C64 programming.
Character Collision in Action
Next, the tutorial explains how collision detection works. The code checks the player’s position against screen RAM, confirming if the player touches a wall, picks up a coin, or enters a door. This approach allows only the player sprite—not enemies—to collect coins. By separating sprite types, you can expand or tweak gameplay with less hassle. Commodore Tutorials gives practical advice for applying these checks across many games.
Updating the Coin Counter
When a coin disappears, the code increases the collected coins variable and updates the on-screen counter right away. To display the number, the tutorial shows how to add 48 to the variable, aligning the value with the right character code for digits. Afterward, the program writes this new value to the correct spot on the screen, so the counter always matches the player’s progress.
Drawing the Exit Door
After the player collects the final coin, the game updates the sprite to a happy face and draws a door using four characters at a fixed screen location. If the player enters this exit, the game resets, setting up a new round. Commodore Tutorials demonstrates how to control game flow, making these transitions smooth and logical.
See It in Action
With clear steps and real code, Commodore Tutorials demystifies screen RAM coin collection for C64 assembly. Because each part is connected to visible results, learning feels rewarding. For anyone ready to try character collision or game counters, this video delivers exactly what you need. Watch now and see these concepts in action—your next C64 game could be just a tutorial away.
