The CP/M, short for Control Program/Monitor, was one of the first operating systems of the personal computer revolution. It was launched in 1974, and it celebrates 50 years this year. It was ported and made available for many 8-bit machines with different CPUs and was related to running productivity software. If you ever used CP/M, then, well, I hate to say it, but you’re old. I had a brief encounter with CP/M when I was 14 or 15 years old; I can’t remember exactly.…

The C128 is a fascinating and unusual machine. It was the last 8-bit Commodore machine before the Amiga and co-existed with the C64 series for a while. They sold ~8 million units worldwide (vs ~17 million C64). I never owned one, but I fondly remember playing with one at my friend’s place and seeing them in computer shops. It’s fully 99.8% backward compatible with its predecessor in C64 mode, but in native C128 mode it takes advantage of its 128 KB RAM, higher clocked 2 MHz 6510 variant (the 8502), and the improved VIC-IIe graphics chip.…

Filipe Cruz (aka psenough) invited me to Inércia 2023, a local Demoscene event organized by the Associação Inércia that took place in the infamous Incrível Almadense. I’ve done my fair share of bouncing ball assembly demos in the 80s and others more recently, but I don’t qualify as a demoscener, not even by the lowest standards. Still, I promptly accepted the invitation. I participated in a panel that discussed the struggles and strategies of organizing community events.…

The ingenuity of combining open-source and open hardware in retro computing is a force of creativity and marvel these days. One of the conundrums with running old computers nowadays is how you display video. I love CRT monitors; I’m a proud owner of a classic 1084S that I use with my C128DCR, but they’re not easy to find in good condition, are expensive, and are increasingly prone to failure with passing years.…

Last year, I decided that I was going to build a Commodore 64 from scratch. This is the blog documenting the project. It’s no secret that I love fiddling with retro computers, especially those I owned when I was a kid. When I revisit ancient technologies and hardware that were part of my younger years, I’m overwhelmed with that warm nostalgia feeling. But it’s not only that. Understanding how old computers work is also educational and helps me look at the modern world with a wiser perspective.…