• TWeaK@lemm.ee
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    1 year ago

    you can store a single bit with a pair of not gates to make a flip flop

    Isn’t it a pair of NAND gates? You can make anything with NAND gates.

    Like this:

    • candybrie@lemmy.world
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      1 year ago

      You can also do it with NOT gates. The driver needs to overpower the gates to change the bit and then it acts like a D flip flop rather than an RS flip flop like NAND gates will. But that’s generally how they’re actually made. SRAM generally looks like this: The side transistors are called access transistors; they’re there so you can selectively read/write, but aren’t needed to store the bit.

    • kautau@lemmy.world
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      1 year ago

      So here’s some bad math. 160 crabs per NAND gate / byte. Doom’s original file size is roughly 2.39MB (I couldn’t find an actual source for this but it’s touted all over the web).

      So 2390000 bytes * 160 crabs is 382400000 crabs.

      So you can run doom on 382.4 million crabs

      Edit: store, not run

      • TWeaK@lemm.ee
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        1 year ago

        They’ve got diagrams of OR and AND gates with the crabs.

        I feel like they would need a NOT gate to do anything meaningful, which obviously isn’t possible. You can’t have zero crabs going in with crabs coming out. Without a NOT gate I don’t think they can do much in the way of traditional computing - you probably can’t run Doom on any number of crabs (although I’d love to be proven wrong).

    • MonkderZweite@feddit.ch
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      1 year ago

      Bistable multivibrator? Must be possible in simpler, no?

      Couldn’t you just move a crab to represent the changed state?