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by davrosthedalek 2533 days ago
You can make memory out of logic gates.
2 comments
accrual 2533 days ago
A flip-flop or latch is one way to store a single bit using just logic gates, using two NOR gates or two NAND gates. [0]

[0] https://en.wikibooks.org/wiki/Electronics/Flip_Flops

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zokier 2533 days ago
Adders belong to category of combinational logic, which by definition excludes memory. So OP is right, they do not yet demonstrate Turing Completeness. I imagine, but don't actually know, that they would be about as expressive as dfa, which are few steps below turing machines
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davrosthedalek 2533 days ago
He builds the adders from ANDs, ORs and NOTs. With these, you can also build flip-flops, which are memory. (Actually, it's enough to have only NAND (or NOR) to build all logic circuits, including memory)
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