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0 pointscrote2mo ago0 comments

It still would't be right. Full-featured USB-C has 8x superspeed (tx1p, tx1n, rx1p, rx1n, tx2p, tx2n, rx2p, rx2n), 2x high-speed (dp, dn), 2x power (vbus, gnd), 2x SBU, 1x CC. That's 15 wires.

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2 comments · 1 top-level

adrian_b2mo ago· 1 in thread

A full-featured USB-C connector has 24 pins, as shown in a diagram in the parent article.

The "12-wire" count of the parent article refers only to the main wires, i.e. the 4 USB 2.0 wires + 4 differential pairs for USB 3 or 4.

Similarly, the "8-wire" count for Type A connectors refers only to the main wires, i.e. 4 USB 2.0 wires + 2 differential pairs for USB 3.

croteOP1mo ago

Yes, but not all of those 24 pins are used, and some of them are duplicated.

I also don't think you can make this "main wire" distinction: you shouldn't be counting the power wires if you only care about USB data in the Type A case, and you should arguably be counting the CC wire in the Type C case if you want to go for "strictly necessary to function", or the SBU wires if you want to go for "carries data at nontrivial speeds".

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