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 »
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 »
After getting the FPGA test rig up and running, the next stage was to attach it to the 6809 SBC. This was critical if I am to incorporate one into the core of my next computer. To start with I utilised the 7 segment displays as an output latch. Since I had 16 bits of display (four seven segments) I… Read more »
In the end I ordered some additional PLCC sockets from the UK and was surprised and happy that they arrived in only a couple of days. Soldering the sockets was easy, considering the board lacks a solder mask. Possibly the use of some liquid flux helped. I was happy with the result although it is not quite perfect: The next… Read more »
When working with solderless breadboard, one of the concerns is how to power it. Ideally I would have a nice bench PSU but, being cheap, I makedo without one. In the past I have stumbled around with various solutions, including using the power pins on a USB serial breakout board, using an AVR programmer header just for the purpose of… Read more »
This blog post is a bit unusual because all I’m able to write about are problems. In short I made up my FLEX6000 dev board but could not get it to function. Here it is in all of its glory: As you can see, I didn’t bother to fully populate it. The route cause of the problem, I suspect, is… Read more »
This last few months has been a bit “scrappy” on the projects front. I’ve not made as much progress as I’d hoped but have started down several different fronts and have done a fair amount of reading. To learn about implementing a DMA controller, I initially started working on a new 6809 computer core on breadboard. In the end I… Read more »