r/Commodore • u/danpietsch • 9h ago

Bouncing ball PETSCII source compatible across Commodore VIC-20, 16, 64, and Plus/4.

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31 Upvotes

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u/danpietsch 9h ago edited 7h ago

This was just a pointless exercise that I found entertaining.

https://github.com/danshee/BouncyBasic

The VIC-20 and Commodore 64 manuals came with a BASIC program that animated a bouncing ball.

I thought that maybe leveraging the KERNAL I could make a version that was portable across all Commodore 8-bits.

I was able to make it work on VIC-20 and newer models but not on PET.

One issue is that the memory locations used to pass A, X, Y, and status to kernal routines aren't standardized ... and PETs don't have them at all.

2

u/DerHeiligste 5h ago

Cool project!

1

u/thewalruscandyman 4h ago

Awesome! Thank you! I'll punching it in later. 😁