This is a quick update from my Restoring a ZX Spectrum+ Toastrack blog. RGB is not analog, we need more colors First, I found that the 6-way IDC analog RGB extender that I used with the RGB2HDMI adapter wasn’t detecting all the colors. Specifically I wasn’t seeing the half bright variant of the 3-bit 8 color palette. 6-way IDC analog RGB extender As you can see I only have 8 colors.…

I talk a lot about Commodore machines in this blog; they left a bigger dent in me growing up, but like most kids of my generation living in Portugal in the 80s, the first computers I played with were actually Sinclairs—first my friend’s ZX81 and then a ZX Spectrum 48K that my parents offered me. I have many memories of playing games like the Horace series, Manic Miner, Jetpac, or Chuckie Egg on my Spectrum.…

I’m on a roll upgrading the Amiga 1000. This time, I replaced the PSU fan. The Amiga 1000 PSU uses an ETRI Model 126LH metallic fan that is AC-powered 220/110V. These fans are pretty good, silent, reliable, and used in computers and industrial-grade equipment. However, they all suffer from a common problem: after long years of continuous use, the fan bearing starts developing an annoying grinding noise due to a lack of lubrication.…

On my last post “the first perfect computer” I mentioned that I wasn’t done with the A1000. I finally upgraded it with an internal RGB2HDMI adapter. For those unfamiliar with RGB2HDMI, it’s a brilliant and affordable open-source project that converts “digital” RGB video signals from vintage computers into crystal clear HDMI video with very low latency. At its core, there’s a combination of a RaspberryPi Zero running bare-metal code and a CPLD (complex programmable logic device) programmed to do level shifting and pixel sampling on the TTL RGB outputs from a vintage computer and feed the processed data into the Pi’s GPIO pins.…

This is a story about restoring and upgrading a Commodore Amiga 1000, the first model of the Amiga series. Many of you might be familiar with the popular Amiga 500 or later models, but the Commodore Amiga 1000 was actually the first model of the Amiga series produced. I consider the A1000 a significant piece of home computing history. Arguably one of the most important machines of the 16-bit revolution period, considered by many to be the first multimedia computer, it marked the beginning of Commodore’s last cycle, after the huge success of the C64, in the history of personal computing.…

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.…