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Ground up projects like this are fascinating! It’s also neat how “ground” has been deepening. It used to mean building mainframe from source. Then building a compiler. Now building from logic gates. How much deeper can you get? Building a mainframe out of Gödel numbers?
Liar. You used NAND gates and a clock.
Liar. You used NAND gates and a clock.
...a clock which can be made from a ring oscillator, consisting of an odd number of NAND gates wired as NOT gates.
(I've never built or simulated that, I'm just trying to imagine what could happen!)
Earlier quoted context omitted.
One curious idea my friends have entertained is to go one level even deeper and emulate the very transistors that make up the NAND gates on the web, too. It would certainly spell disaster for performance, but it's without-a-doubt interesting.
That would be fascinating! Do you know any resources that document the transistor to logic gate translation?
The electromechanical relay is a very simple device to understand, if you're willing to just believe that electromagnets produce magnetism (without understanding why the universe works according to Gauss's laws on the relationship between electric current and magnetism). It's a coil of wire where an electric current produces magnetism that physically pulls a switch open or closed.
Earlier quoted context omitted.
...a clock which can be made from a ring oscillator, consisting of an odd number of NAND gates wired as NOT gates.
How do we know that that will converge to a single constant period of oscillation? Could you have a few different-sized square waves continue to cycle through the circuit? (I've never built or simulated that, I'm just trying to imagine what could happen!)
No.
Cool project. It reminds me of a theoretical issue. As the project page says, this system is clearly Turing equivalent. Since it runs software, it even implements a _universal_ Turing machine. But the design uses only (synchronic) sequential logic [1] and Wikipedia seems to suggest that automata theory considers sequential logic only equivalent to finite state machines. Not Turing machines. Isn't that clearly a major…
Real-world computers are equivalent to linear bounded automata, not true Turing machines, because they have finite memory. This technicality is mostly ignored because a computer with a large finite memory is a decent enough approximation to a Turing machine for practical purposes. But, for example, the halting problem is decidable for linear bounded automata — because there are only finitely many states, every comput…
Yet we know this doesn't happen in practice.
[0] https://en.wikipedia.org/wiki/One-instruction_set_computer
Earlier quoted context omitted.
How do we know that that will converge to a single constant period of oscillation? Could you have a few different-sized square waves continue to cycle through the circuit? (I've never built or simulated that, I'm just trying to imagine what could happen!)
>Could you have a few different-sized square waves continue to cycle through the circuit? No.