Lab Notes

Experiments with computing, electronics, and maker crafts.

Ladder on a Modern PC

December 21, 2022

One of my favorite home computer games from early childhood is Ladder for the Kaypro, an action platformer rendered entirely in text characters. Here’s how to play it on your modern PC.

Advent of Code on the MEGA65

December 4, 2022

Advent of Code, the annual non-competitive puzzle event for computer programmers, has begun for 2022. Here are a few tips for anyone who might want to try this year’s AoC on the MEGA65.

C projects with GNU Autotools in 2022

August 18, 2022

I’ve been a user of the GNU Build System (aka GNU Autotools) nearly all my life, as the installation mechanism for countless open source software packages. Only recently have I tried setting up a software project that uses it. I ended up with a new project template and a lightweight C module management system, with unit testing and mocks.

Using MEGA65's Matrix Mode

July 31, 2022

The MEGA65 has a powerful debugging facility built into it that would have been high fantasy for vintage computer programmers back in the day: the Matrix Mode debugger. Today in Lab Notes, we explore Matrix Mode’s capabilities to further help us with assembly language programming, continuing to use our Game of Life program as an example.

Using the MEGA65 Monitor to troubleshoot assembly programs

July 26, 2022

When we last attempted an assembly language program for the MEGA65, I described debugging techniques that involve inventing ways to visualize the memory and behavior of your program, often requiring adding code to the program temporarily to do so. Today I want to explore a feature of the MEGA65 that can help with this, the MEGA65 machine language monitor, using our Game of Life program as an example.

Game of Life on the MEGA65, in assembly language

July 23, 2022

Previously, we explored Conway’s Game of Life for the MEGA65 in BASIC. Let’s try it again, this time in assembly language, using the same BASIC timing code for comparison.

Game of Life on the MEGA65, in BASIC

July 20, 2022

Conway’s Game of Life is a classic math game that’s also a fun beginner’s programming project. With a grid of cells and a few simple rules, a flourishing biome of digital organisms comes to life. Let’s try building it for the MEGA65 using BASIC!

Adding a feature to the MEGA65

June 17, 2022

On every Commodore computer that has a Home key, I routinely hit Home when I mean to hit the Del key. The only way to move the cursor back to where I need it is with the arrow keys. With the MEGA65, I finally have the opportunity to do something about this, once and for all.

Welcome to the MEGA65

June 12, 2022

The MEGA65 is a new personal computer based on the Commodore 65, the unreleased 1991 sequel to the inimitable Commodore 64 and 128 home computers of the 1980’s. I’m so excited about mine, I wrote the MEGA65 Welcome Guide, a supplementary booklet for new owners.

MEGA65 BASIC fun: Balloon sprite

May 20, 2022

#mega65 BASIC fun! @JudgeDrokk invited me to answer @HeadingtonBard’s question about #mega65 BASIC, so here’s an attempt! 🧵