The past few months have been slow for MENTAL-1, but a few important milestones happened. Most importantly, I'm officially calling it finished. The MENTAL line of processors is most definitely not, but MENTAL-1 is. It's able to achieve stable operation at 3MHz, has working peripherals that were designed for it (the PS/2 keyboard input and the 40x2 character display output), and most importantly has a slick laser-cut case. I've included the most recent video I have of it in operation - it's one I created for showing the computer to a few different Reddit communities.
One of the best things to come from this project was being able to use it as a tool to teach others about building their own CPUs. At the Seattle Mini Maker Faire, I had a blast introducing the ideas behind how computer chips are made, how digital logic works, and how creating a large hand-wired project like this can be tedious but incredibly rewarding.
The CPU was running the simple "cat" program I had written, and visitors were able to stop by and type out any message they wanted. The new case on it helped keep my mind at ease when the younger crowd stopped by and wanted to get hands-on.
I was able to attend the Wenatchee Mini Maker Faire as well, which was much more relaxed but still a great time. It was a bit after the one in Seattle, so I had time to polish my presentation a bit.
It's been a blast sharing this with local communities.
So, what's the plan now? MENTAL-1 is finished. I've started work on MENTAL-2, which is fairly messy but much more compact. I'm currently working on an FPGA implementation as well.
I'll post proper schematics, the source code for my "cat" program, and my notes here in the coming months.