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I made a small game inspired by the first lessons in the course: http://nandgame.com/
Earlier quoted context omitted.
Thanks, that page is nice, but it too emphasizes that you also need a clock. That's essential and it was the point I was trying to make. For example, a thing that is usually glossed over in OS courses (in favor of, let's say, scheduling algorithms and such) is that you simply can't make preemptive multitasking out of pure code - and later when you ask yourself how is it that such a phenomenon is possible in the first…
Couldn't you in theory build a clock purely from nand gates? You create a cycle of nand gates where the output of one is tied to both inputs of the next. If the cycle have an uneven number of nand gates, each nand will oscillate with a period depending on the length of the cycle.
You can use NAND to make NOT.
The title of the course is misleading, as it suggests that NAND gates are the only required primitive, whereas the course later introduces DFF gates, without which you cannot escape the parallelism of chips.
And one thing that is said even less is why NAND? You can do it all with NOR gates as well if you want. The reason for NAND has to do with the switching speed, pMOS switches quicker in parallel (either transistor can get the current flowing) and nMOS switches quicker in series (either transistor can stop the current flowing); this is how a NAND gate is wired. NOR gates on the other hand have the worst of both. The fa…
The Apollo computer, which used bipolar instead of CMOS, indeed did use all NOR gates:
http://klabs.org/history/ech/agc_schematics/
http://mikestewart.hcoop.net/2015/09/21/interpreting-the-sch...
https://www.amazon.com/Code-Language-Computer-Hardware-Softw...
The title of the course is misleading, as it suggests that NAND gates are the only required primitive, whereas the course later introduces DFF gates, without which you cannot escape the parallelism of chips.
And one thing that is said even less is why NAND? You can do it all with NOR gates as well if you want. The reason for NAND has to do with the switching speed, pMOS switches quicker in parallel (either transistor can get the current flowing) and nMOS switches quicker in series (either transistor can stop the current flowing); this is how a NAND gate is wired. NOR gates on the other hand have the worst of both. The fa…
Earlier quoted context omitted.
Couldn't you in theory build a clock purely from nand gates? You create a cycle of nand gates where the output of one is tied to both inputs of the next. If the cycle have an uneven number of nand gates, each nand will oscillate with a period depending on the length of the cycle.
https://en.wikipedia.org/wiki/Ring_oscillator You can use NAND to make NOT.
Earlier quoted context omitted.
And one thing that is said even less is why NAND? You can do it all with NOR gates as well if you want. The reason for NAND has to do with the switching speed, pMOS switches quicker in parallel (either transistor can get the current flowing) and nMOS switches quicker in series (either transistor can stop the current flowing); this is how a NAND gate is wired. NOR gates on the other hand have the worst of both. The fa…
During my intro to computer engineering course, lectures touched on why NAND gates, and the conclusion was that you can build anything you need in a basic computer using NAND gates. It boils down to expense. A BOM (bill of materials) with fewer line items tends to be cheaper. This doesn't really hold in today's world of silicon prints, but at the start I think it was price that drove the decision.
If you would like to start at a slightly lower level, Charles Petzold has written a great book on the subject: https://www.amazon.com/Code-Language-Computer-Hardware-Softw...
If you would like to start at a slightly lower level, Charles Petzold has written a great book on the subject: https://www.amazon.com/Code-Language-Computer-Hardware-Softw...
... cleverly illustrated and eminently comprehensible story ... No matter what your level of technical savvy, CODE will charm you—and perhaps even awaken the technophile within.
Code doesn’t sound “slightly lower level”.