Commodore GEOS Resource Centre

Stylized globe showing western hemisphere with the name GEOS superimposed.

I was once a GEOS power user. My setup had a 1541, 1581, JiffyDOS, a 1764 RAM expansion unit (expanded up to 512Kb), a 20Mb hard drive for long-term storage, and the SuperCPU from Creative Micro Designs which allowed the C64 to run at twenty times its regular speed. With the Perfect Print LQ system and a 24-pin printer, my documents looked so good that you could hardly tell that I was using outdated hardware. I kept that system running as my everyday computer until I got my first iMac at the end of 1999.

I used to be the main GEOS contact for the Usenet newsgroup comp.sys.cbm which meant I'd get emails from around the world from users with questions. I heard from total novices looking to get started and experienced programmers trying to navigate the memory map of the GEOS Kernal. But after a while, the questions stopped coming. The world had moved on.

With the release of the C64 Ultimate (C64U), there's been a renewed interest in GEOS. While there are already excellent GEOS resources online, I've decided to add my own perspective to the conversation with beginner-friendly guides and historical documentation that preserves both the software and the everyday experience. I was there, and I can tell you what I saw.

I don't use GEOS every day anymore and I've forgotten nearly everything I used to know, but I've started refamiliarizing myself with the GEOS ecosystem. I'll write about everything I learn (and relearn) here. I guess I'm back in the answer business.

Feel free to drop me a line if I can once again "be of help".

Contents

Getting Started with GEOS
Surviving your first half hour with GEOS 2.0 on the Commodore 64 Ultimate, based on my first look at the operating system in 25 years. It did not go exactly as planned.
Customizing GEOS
A minimal setup is less than ideal. Here's how you can set up a reasonable custom GEOS installation using only the C64U, "The Very Second" file collection, and an optional joystick.
The GEOS User Experience
COMING SOON! GEOS can feel a little strange to a modern user. Many of the conventions we take for granted hadn't been standardized yet. Let's look at some of the differences.