Talk:2497: Logic Gates

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As someone has just Transcripted basically almost all the fine detail I had planned to entable in the Explanation, I shall not now create repetition. Though I had a little more description to the NORXONDOR GOGONAX, in particular, to reference bidirectional (antiparallel) diode pairings (e.g. an LED assembly that glows a different hue depending upon the applied current bias) as probable inspiration, and that latched Flip-Flops surely inspired some part of the Frankensteinian gate-types, too. 00:08, 3 August 2021 (UTC)

(Also, surprised there was no direct "GONDOR" reference. Or maybe that's because it was too obvious?) 00:12, 3 August 2021 (UTC)

I was also missing a "GONDOR" reference, and all the X's also made me think XEHANORT. 03:49, 3 August 2021 (UTC)

...So, who's ready to draw up some truth tables? 01:22, 3 August 2021 (UTC)

I can't get the lines in the bitwise-operation example to align properly; the first one is indented a tad. Can someone please fix that? Thanks... BunsenH (talk) 04:11, 3 August 2021 (UTC)

The symbol for norx gate (1-input OR, two outputs) I'd read as a noninverting buffer to increase another gate's usable fan-out. Xand gort resembles the symbol for an op-amp. Given the subtraction that an op-amp does, the xand gort's truth table probably resembles that of the "implies" operator. Tepples (talk) 04:23, 3 August 2021 (UTC)

the "NORG XORT" is not equivalent to an XOR, as the symbol is round on the right. -- 06:39, 3 August 2021 (UTC)

Right, "NORG XORT" would be a XNAND with inverted inputs, though I don't know what the logic table from a XAND or XNAND gate would look like. If De Morgan applies to XAND/XOR the same way as with AND/OR, would a "NORG XORT" then be equivalent to a XOR ? 15:12, 3 August 2021 (UTC)

I think it is specifically a hybrid between XOR and NAND. The left edge is curved like OR, and the right edge curved like AND. I did spend some time thinking about XAND, though. One of my ideas was a >2-input AND that is only true if exactly 2 inputs are true. I wonder what qubit gates are like. 16:16, 3 August 2021 (UTC)
Logic Gates

It seems to me that their ought to be 16 possible logic gates. Although some would ignore one or both inputs. Algr (talk) 07:18, 3 August 2021 (UTC)

Yes. The 74181 4-bit arithmetic logic chip implements all 16 possible binary logic operations. See 07:34, 3 August 2021 (UTC)
It doesn't say the names of the various gates. On my list I made up a few, like "Only B" that only returns true if B is true and A isn't. Are their real names for this? Algr (talk) 18:57, 3 August 2021 (UTC)
I could suggest "Unless" (as in 'B unless A', or maybe to counterpart 'A unless B' with standard order of operands, 'A disallows B'). Though the partially composite construct '!A && B' would be easier to grasp by those already handling logic statements, I think. 19:24, 3 August 2021 (UTC) -- 23:02, 3 August 2021 (UTC)
So "Only B" is called "Converse nonimplication"?! Maybe I'm the only logical person. Algr (talk) 06:30, 4 August 2021 (UTC)
As Randall drew gates with two outputs, these would have 256 (16^2) possible functions 15:15, 3 August 2021 (UTC)
That couldn't logically be anything but two logic gates sharing the same input. Algr (talk)

there should be a category of comics where it starts out like a normal list and gets weirder and weirder like Trig Identities 18:53, 3 August 2021 (UTC)Bumpf

What, no IMPLIES gate? I actually used this once to implement a NOT operation in a database see search. Joem5636 (talk) 11:00, 4 August 2021 (UTC)

It appears to me that the new gate names are just taken from the letters of the original gate names: NAND, NOR, XOR,and GATE. They're just stuck together in ways that tickled the creator's fancy. 11:11, 4 August 2021 (UTC)