5 years ago, I made a derivative of SAP-1 (mainly inspired by Ben Eater) on breadboard with few improvement and called it MSAP-1 (https://github.com/mehrantsi/MSAP-1) I made my own very primitive Assembly language and a simple Arduino programmer (https://github.com/mehrantsi/8-bit_CPU_Programmer) where I could load my programs onto MSAP-1 and even Debug them (https://github.com/mehrantsi/8-bit_CPU_Debugger).

After that I started worked on the second version of it (https://github.com/mehrantsi/MSAP-2) by adding Stack, Interrupts and etc. with the goal of having a very primitive OS running on the second version, but changes in life meant I didn't have time to work on it as much, but I was progressing.

Since 2 years ago, I had this little test of mine to see which one can understand MSAP-1, My own Assembly, the programs I wrote and ultimately if they would understand MSAP-2. none of the models could really understand the whole stack and initial models were quite bad at understanding hardware and electronics in general. Until Fable 5...

Same prompt to Fable and it's the first model that understood the full stack and my intentions for the second version that is in progress. I asked it to create a simulator which it did (not one shotted ofc) and I managed to finalize the design using that. Then together with Fable I created an OS using my own Assembly (https://github.com/mehrantsi/MOS-1) and loaded it there and it all works!

It's all quite fascinating how much better at electronics Fable is compared to the predecessors!

Simulator for MSAP-1: https://msap1.mehran.dk

Simulator for MSAP-1: https://msap2.mehran.dk