Comment by eugene3306

4 years ago

just curious. Can USB3 work without D+ and D- ?

USB 3 and previous standards are completely separate connections and software stacks - the USB 1/2 D+/D- pair does not interact at all with SSRX/SSTX. You should be able to literally cut the D+/D- wires in an USB 3 cable and it should still work as a USB 3 cable.

  • I doubt any normal hosts will enumerate a USB device without the USB 2 data lines. PD will definitely not work. You might be able to get an alt mode running.

    • They probably would enumerate just fine, because the SuperSpeed enumeration is completely independent from the USB 2.x enumeration. USB-PD uses a separate pin/wire, not the USB 2.x D-/D+ pair, and you cannot get an alt mode running (except the special analog audio and debug accessory modes) if USB-PD doesn't work, since alt mode enumeration goes on top of USB-PD.

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