code · retro
Matrix Math on a Commodore 64
Matrix fundamentals from the ground up. Definitions, the operations that matter, plain Python, numpy for comparison, and a complete BASIC program on a …
commodore · c64
The SID Chip Is a Reservoir Computer
Reservoir computing says don’t train the dynamics, just train the readout. I used the SID’s analog filter as the dynamics and one ridge …
code · retro
WOZMON, Eight CPUs, and a Paper Tape
Eight CPUs from the 1970s and 1980s, sharing one 64K bus, an Apple-1 style monitor on the front, and a paper tape station. Open it in your browser and …
code · retro
Forty-Three Quintillion on a Commodore 64
Where the famous 43 quintillion comes from, why a C64 can’t print it the easy way, and a tiny multi-precision multiplier in BASIC that gets …
retro · Timex
Fixing a Timex Sinclair 2068 and Porting the Bond Maze
I picked up a boxed Timex Sinclair 2068 that wouldn’t boot. An oscilloscope, a BackBit tester, and a fresh Z80 later, it was running. Then I …
code · retro
Biological Processing Units and a Commodore 64
The fruit fly has a brain structure that acts like a hash function. I built it in Python, matched the 2017 paper’s MNIST results against a …
code · How-To
Breaking Enigma with Index of Coincidence on a Commodore 64
The Bombe needs a crib. What if you don’t have one? Index of coincidence measures how much an output looks like real language vs random noise. …
code · How-To
The Wallis Product for Pi on the C64
John Wallis found an infinite product for pi in 1655. Multiply enough fractions together and pi falls out. We run it on the C64 in BASIC and assembly, …
code · How-To
Enigma Ring Settings on the Commodore 64
Ring settings multiply Enigma’s keyspace by 17,576. We add them to our C64 emulator, see why brute force alone can’t keep up, and set the …
code · How-To
Breaking Enigma on the Commodore 64
The Commodore 64 searches nearly six million Enigma M3 configurations to find the one that matches a known plaintext crib. First the concept, then …
code · How-To
Enigma Emulator on the Commodore 64
A working Enigma M3 emulator on the Commodore 64. First in BASIC for clarity, then in 6502 assembly for speed. Eight rotors with dual notches, …
code · Getting Started
10 PRINT on the Apple II
Bringing 10PRINT to the Apple II with Applesoft BASIC and Lo-Res graphics, exploring both text-mode and graphical approaches to this iconic one-liner.
retro · Enigma
The Math Behind Enigma
Why German cryptographers believed Enigma was unbreakable, and why Allied codebreakers ultimately proved them wrong.
code · Getting Started
Sorting Algorithms Visualized on the Commodore 64
Visualizing sorting algorithms in real-time on the Commodore 64 using PETSCII characters. Three classic algorithms rendered as animated bar charts in …
AI · programming
First Principles: Why You Must Learn Before You Prompt
Vibe coding with AI feels productive until it isn’t. Dorothy Vaughan’s team didn’t just operate the IBM—they understood the math …
history · programming
Dorothy Vaughan: Adapt or Become Obsolete
When IBM machines threatened to make her job obsolete, Dorothy Vaughan didn’t retreat—she learned FORTRAN and taught her entire team. Her story …
code · Getting Started
Three Maze Generators on the Commodore 64
Exploring three different maze generation algorithms on the Commodore 64: Depth-First Search, Randomized Prim’s, and the classic 1981 algorithm …
code · How-To
16-bit Unsigned AND on Commodore 64
Implementing 16-bit unsigned AND operations in Commodore BASIC using two’s complement to work around the signed integer limitation.
code · Getting Started
The Best Book Cover of All Time
Celebrating the gloriously absurd cover of ‘FORTH on the Atari’—possibly the greatest unintentionally funny book cover ever created.
code · Getting Started
10 PRINT for the KIM-1
Implementing 10PRINT on a KIM-1 clone (PAL-II) in both Microsoft BASIC and 6502 assembly, displaying the maze on the 7-segment LED display.