This past few months has been spent thinking about, and prototyping, ideas for the Operating System I want to write for the computer. But before talking about that, a summary of the other little pieces of hardware progress. Anyone who has viewed the video will be familiar with most of this.First up SPI. I have implemented a trivial SPI controller… Read more »
Physical construction of the MAXI09 PCB is now complete. A final, 3 hour, session with the soldering iron completed that task. Here is a picture of the top of the board: I have also found a solution to the problem of unwanted flux residue. After trying out various things including isopropyl alcohol, it seems that the best approach is good old… Read more »
Construction of the MAXI09 is continuing. With each part soldered onto the board comes a limited amount of testing with the monitor. Enough to exercise the very basic level of functionality, nothing more. Proper testing, and actually making the part do cool things, will come later. The first part added was the OPL2: Since this was previously prototyped on breadboard… Read more »
After a wait of only about a week and a half, I have now received five MAXI09 PCBs from Botech. Here they are in the wallet: I was surprised at how much they all weigh! And the bottom: As you can see, they look great. Especially noticeable is the silk screen which is beautifully crisp and clear. After doing some… Read more »
Two more bits of prototyping work have been completed recently. The first is the keyboard controller portion. Since the MAXI09 now includes a new Amiga 600 keyboard, and because this keyboard has many more connections then the old C64 one, I have mocked up the controller on breadboard. I was able to establish the pining on the 30 way flex… Read more »
I have been busy the last few weeks prototyping up the remaining untested parts of MAXI09. The first thing I wanted to do was to confirm the functioning of the AD8013 (PDF) video amplifiers. This did not go well at all. After attaching one to a SOIC-14 breakout adapter and plugging it into the circuit on the breadboard, I was… Read more »
Pretty much since I first started using it, about two years ago now, I have been struggling to “like” gEDA. To be fair, it has many positives. The schematic capture tool is not terrible to use. It is certainly quirky. The totally non standard keyboard shortcuts being just one example of this quirkiness. But it has, in my view, significant… Read more »
I have finally solved the issue with holding multiple FPGA designs inside a single configuration flash. It seems there is a special tool just for the purpose of creating complex program files (.pof files). The details are buried in this document. So this is great news, though since I only have one PLCC84 adapter made up I won’t be able… Read more »
My last post was full of text, and therefore not very approachable. This post will hopefully explain some of my thoughts in a clearer way, with the diagrams and schematics (hopefully) doing most of the talking. First up here is the current, work in progress, system overview: (I tried looking for some nice online tools for making these kinds of… Read more »
This blog post is concerned with planning and, unlike pretty much all my posts to date, is not concerned with things I’ve actually done. My new computer is coming together nicely, at least in my mind and in some rough plans. Here is a list of what I hope will be the main hardware features: 6809 based (naturally) 512KB of… Read more »