Click the image above to take you to the live simulator. As it runs, the wires dynamically change color on a cycle-by-cycle basis as the logic states of each wire update.
It makes my head spin to think that the CPU from the first real computer I used, the Apple II, is now simulateable at the mask level as a browser plug-in. Nothing to install, and it’s Open-licensed. How far we have come…a little more than a decade ago, completing a project like this would have resulted in a couple PhDs being awarded, or regarded as trade secret by some big EDA vendor. This is just unreal…but very cool!