News for hackers. Stuff that matters.

A comment on M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2. Parent comment

Re:M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2 by grishka on Monday April 18, 2022 @10:07AM (#31070778)
I have some Android phones that have a USB-C port but only support 2.0 speeds (as per the macOS system info USB tree thing). Which version is that then? I've always assumed that the physical layer of the protocol and the connectors themselves were separate specs and you could have USB protocol running over any kind of arbitrarily shaped connector. And no protocol over a USB(-A) connector, because those are de-facto low-power DC outlets now, among other things.
[ Parent | on HN ]
Re:M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2 by kevin_thibedeau on Monday April 18, 2022 @12:16PM (#31072719)
The USB-C connector has a dedicated legacy USB 2 pair that is always available. This is the same as an upgraded (usually blue) USB-A connector with the addition of mirrored pins.
[ Parent | on HN ]
Re:M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2 by coryrc on Monday April 18, 2022 @12:25PM (#31072840)
It's 3.1 or newer, full speed device.

Why normal people should care about the spec version is weird to me.

The spec does specify the connectors for using the USB logo and claiming compliance. But if you don't care about compliance then use whatever connector you wish!

[ Parent | on HN ]
Re:M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2 by ta988 on Monday April 18, 2022 @11:02AM (#31071613)
Note that in my experience MacOS (M1) is pretty bad with USB devices, I have a lot of things that just don't work properly on the Mac but work on Windows and Linux (ebook reader and phones for example).
[ Parent | on HN ]
Re:M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2 by giantrobot on Monday April 18, 2022 @10:37AM (#31071229)
Very likely the Android device doesn't advertise any particular USB spec. If anything it might have a logo for the minimum spec it supports. You can put USB controllers in a device and not worry about any USB-IF if you don't use any USB branding on the box, IIRC any licenses owed are covered in the price of the ICs.

The logical connection in USB doesn't care about the physical connection. Your phone could just have some soldered leads for all the protocol cares.

[ Parent | on HN ]
Re:M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2 by notatoad on Monday April 18, 2022 @03:14PM (#31075133)
I think that version is called "we don't give a fuck about what the USB-IF thinks"
[ Parent | on HN ]
Re:M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2 by Dylan16807 on Monday April 18, 2022 @04:35PM (#31076151)
I'm pretty sure 2.0 C cables are entirely legal by the standard.

Unlike charge-only cables...

[ Parent | on HN ]