Ace
A few months ago I found I had enough time on my hands to get on with something I 've been planning for 20+ years and that was to create a new Jupiter Ace. At one point I'd started porting the ROM to the Raspberry PI bits of it even run, but the problem was that the PI is quite a closed system finding out the details of the CPU and Graphics system is difficult and hidden behind a veil of secrecy and IP. The system I wanted to create would be simple and easy to understand at all levels. The first step was to find some schematics in a system I could get for free. Bodo Wenzel had done some nice ones here but in OrCAD which costs money. He did, however, provide images of the work so off I set with the free version of Eagle CAD. I downloaded the PDFs to get a good look. I translated the above eventually to Which is available in KiCad format here . Then built a cut down version to show the diagrams were correct. All the routing is done by FreeRouting because I'