10PRINT on All the Things

One line of code. Endless mazes. Every platform I can get my hands on.

The One-Liner That Started It All

In 1982, someone typed this into a Commodore 64:

10 PRINT CHR$(205.5+RND(1)); : GOTO 10

And a legend was born. This simple program randomly prints diagonal characters, creating an infinite maze pattern that fills the screen. It’s become the “Hello World” of generative art and a rite of passage for retro computing enthusiasts.

The original uses PETSCII characters 205 and 206 (diagonal lines that connect perfectly). The trick? Adding 0.5 to 205 and letting BASIC’s integer conversion randomly round up or down. Elegant. Minimal. Perfect.

The Quest

My mission: implement 10PRINT on every platform I can find. Vintage computers, graphing calculators, fantasy consoles, modern languages. If it computes, it can maze.

Each platform brings its own challenges. No PETSCII characters? Use ASCII slashes. No text mode? Draw lines. Only a 7-segment LED display? Get creative.

Vintage Computers

The original playground for 10PRINT. Each machine has its own quirks, character sets, and limitations.

Calculators

Who says calculators are just for math? These pocket computers can maze with the best of them.

Modern Languages

How fast can 10PRINT run on modern hardware? Let’s find out.

What’s Next?

The quest continues. On deck: ZX81, BBC Micro, and who knows what else. Got a machine you’d like to see running 10PRINT? Let me know.

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