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.

Modern and retro mix

One of my favorite peices of retro clone hardware is Bob Corsham’s KIM-1 Clone. I’ve featured it many places like the 6502 speed series.

I have the latest model of this board, and he made an interesting design choice. It actually has an FTDI chip on board and you use that via USB to connect via a modern computer with an FTDI driver. This is very convenient for working with a modern computer, but then eliminates the ability to use a real serial port.

Driving LEDs from the VIC-20 and KIM-1 USR ports. Binary counting in the real world with vintage hardware.

Exploring the elegant maze generator from Compute! magazine (December 1981). A line-by-line breakdown of how this classic BASIC algorithm works.

Writing code to validate Pilish text—prose where word lengths match the digits of Pi. Implementations in Julia and Commodore BASIC.

Evaluating vintage computers for NaNoWriMo 2022: VIC-20, Plus/4, Commodore 64, and PET. Word processing on 8-bit machines with SpeedScript and other tools.

Understanding the MOS paper tape format used by the KIM-1 and other 6502 systems. Breaking down the hex format line by line with checksum verification.

Optimizing 6502 memory transfers beyond the general-purpose approach. Testing on a 1MHz KIM-1 clone with precise timing measurements.

Testing real-world memory transfer speeds on 6502 machines. Inspired by Apple M2 marketing, let’s see what Commodore hardware can actually do.

Finding k-almost-primes using TinyBASIC on a KIM-1 clone. A look at the copyleft origins of TinyBASIC and Bill Gates’ infamous open letter.

Implementing 64-bit arithmetic in 6502 assembly to solve the wheat and chessboard problem. Handling numbers too large for standard calculators on 8-bit machines.

Computing and displaying the first 10 Fibonacci numbers on a KIM-1’s hex display. Learning 6502 assembly the hard way with pencil and paper.