Comment by bb88
16 hours ago
> I don't see circuit-as-code taking off with humans anytime soon
I don't agree with this. Circuits aren't really anything more complex than anything else humanity has had to figure out. Most knowledge in this area seems solvable.
Maxwell's equations have been known for a century.
For whatever reason, Software Engineering and Hardware Engineering even though they rely upon the same fundamental physics, are so very different? And apparently can't be reconciled? No. I don't believe it.
> For whatever reason, Software Engineering and Hardware Engineering even though they rely upon the same fundamental physics
They are completely different. Software is pure mathematics: you know exactly what goes in, you know exactly what operations it is going to do, and you know exactly what will come out. There are no surprises here, it's just a mechanical translation. If you want to, you can even prove that your code is doing the right thing.
Hardware is physical. Your components don't neatly follow mathematical models - the model is just a rough approximation. Everything interacts with everything else: a signal in one trace will impact a signal in the next trace over - or even on the other side of the board. Your PCB will behave differently if you hold your hand above it - without even touching it. Worst of all, most of your components are black boxes, and you don't have accurate models describing them! What good are Maxwell's equations if there's no way you're ever going to solve them?
You can make a reasonable estimate of how a PCB is going to behave, and you can occasionally do a reasonably-close simulation of some part of your circuit-to-be in isolation. But you need to physically manufacture it to find out whether it behaves the same in practice, and it takes weeks of time and thousands of dollars to manufacture a single prototype. You can't "move fast and break things". You can't afford to do the usual "hit a bug, change tiny thing, recompile, check" cycle you're used to from software programming, and some fancy tooling isn't going to change that reality.
PCB layout is as much art and black magic as it is science. I'm not sure why you dismiss the complexity so easily, this definitely is not just a matter of applying Maxwell's equations.
Layout is a puzzle, especially with particularly high density layouts, but some of this is ameliorated by high layer count and fine trace/space boards becoming cheaper. Definitely not black magic. RF layout is black magic, let's not steal their thunder here.
High speed PCBs are RF. At high enough frequencies, traces become waveguides, and the result cannot be predicted analytically. Simulation is your only light in this mess.
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> For whatever reason, Software Engineering and Hardware Engineering even though they rely upon the same fundamental physics
Software engineering isn't a thing besides being an ego title.
Software is "ship now, patch later"
Hardware is engineered, it must be correctly designed from the beginning and cannot be easily modified in the field
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