The day ALU pins expanded my brain
I remember sitting in the basement of the DCL building at UIUC one day working through an MP for my computer architecture class. We had been working up from logic gates up through subcomponents to a basic computer architecture - from multiplexers, gates, and decoders up to the ALU, program counter, clock, etc. The problem I was working on had something to do with connecting them all together such that the clock would tick, a new instruction would be loaded into memory, the program counter would be incremented, etc. The instruction had to come from the inputs from a combination of muliplexers, decoders, and so forth. These would be pins with high/low voltage, that would feed into these subcomponents to represent an instruction.
Now, keep in mind I had learned to code at a young age. I'd been writing BASIC and Java for years at this point. I was familiar with C and C++, and had a rudimentary understanding that C could be seen as an abstraction on top of assembly, and that assembly itself was an abstraction on top of machine code. Machine code being those 1s and 0s. But I'd spent most of my time way up high in the application layer, often in network-land as well.
As long as I live I will never forget the moment I realized that the pin inputs to the primitive CPU I had built, the pins that expected high voltage or low voltage, were really 1s and 0s. I remember sitting there dumbfounded as these two large bodies of knowledge in my head, previously unrelated, all of a sudden connected. And not only did they merely become related to one another, they became deeply connected, one nesting inside the other, or one on top of the other, depending on how you see it.
It felt like my brain literally expanded. It felt like my perspective increased drastically in a single moment. It wasn't like one day I understood both computer architecture and programming, and the next day I understood them both together. It was more when Neo could see the matrix. The visceral sense of clarity and altitude was palpable, literal. I remember looking around at the other people in the lab and nobody else seemed to notice me. But I felt like I had cracked a secret code of the universe.