All hail PCBWay!

Yes, this is a sponsored post. I’m not going to be bashful about it, in fact I’m proud! I have a sponsor: it’s PCBWay. They – as you have guessed I’m sure – make PCBs. From quick-turn, low volume prototyping to small(ish) production runs.

Their support includes the usual 2-layer affair, but multi-layer and rigid-flex designs aren’t beyond their capabilities. They can manufacture buried and blind vias, even laser-vias if that’s what you fancy.

Pretty nice, but just that wouldn’t be all that outstanding: there are many companies doing that. PCBWay however also do CNC machining, 3D printing, make SMT stencils for you, even buy and put the components on your circuit boards.

In one word: they are your one-stop prototyping shop. They are mine.


The other day I felt nostalgic and wondered over to the great site, originally to look for Commodore 64 material. Then, I thought, what the hell! and typed ‘cray’ into the search box. Lo and behold, a lot of hits! There are manuals, a CD image with some marketing or teaching material on it, but among them, two interesting CD images:

Both are UNICOS install images. I’ll have to see if they are complete and what version (and for what machine) they are, but I wanted to share the news: it appears that there is now a publicly available OS image (maybe even two) for my simulator.

Cray update

Recently I’ve noticed that the C compiler hung on the simulator. I’ve tracked the problem down and fixed it. The online version as well as the latest sources should have it fixed and working.

For the curious, I’ve written up a small story on the reasons and the fixes.

More retro-computing

I ventured into the past again, this time by reviving an old ZX81 computer. The short project included expanding the original memory to 16k and to correctly output video from the old dinosaur.

You can read about the adventure and download the design files in case you want to replicate my work from here.


Well, that’s a mouth-full. It stands for ‘Vintage Computer Festival, Pacific North-West‘. It’s happening this weekend, and I’m presenting the Cray work I’ve been doing. Which reminded me that I should also update this page with direct links to all the random babbling I’ve done about this project over the years.

First off, all the articles about the Cray XMP and COS restoration work:

  1. Prelude
  2. A New Hope
  3. The Hunt for the Red Bootcode
  4. The Return of the Cray
  5. The Matrix
  6. First update
  7. Needle in the Hay-stack
  8. A Brave New World
  9. Multiple Platforms
  10. Jobs
  11. Parallels
  12. Turbo

The second series is about the newer, J90 (and YMP-el) simulation work, running UNICOS:

  1. A Bridge too Far
  2. That Obscure Object of Desire
  3. Exploring the CD
  4. A New Simulator, part 1
  5. A New Simulator, part 2
  6. A New Simulator, part 3
  7. The UNICOS file-system
  8. Oldies but goodies
  9. A debug session
  10. To SSH and beyond

You can download the latest version of the simulator (including source code).

However if you’ve read all the above (as I’m sure you just did), you’ll know that the download page doesn’t actually contain functional UNICOS images: I don’t have the rights to distribute them. Because of that, I’ve put the simulator on-line, so – while you still can’t run it yourself – you can experience the full glory of a late 20th century supercomputer.

To anyone coming here because they ran into my exhibit on the VCF PNW, thank you again! For everyone else, still thank you for dropping by my page and enjoy!

The Return of the Cray files

Good news everyone!

A very nice gentlemen – who decided to remain anonymous – contacted Chris and me, saying he has some X-MP tapes we might be interested in. As it turned out he has an absolute treasure chest of material, in fact much more than ‘just’ a collection of X-MP tapes.

This gave me a reason to re-start my work on the Cray simulator project, in fact I’ve decided to start a new series. If you’re interested, check it out here.