Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

USB Cheat Sheet (2022)

fabiensanglard.net

Post reply on HN
Print view View original

41–50 of 89 posts

Re: USB Cheat Sheet (2022)

#42

Post by altairprime »

DHowett wrote: post #10

Excellent article. If I could offer one correction, it would be that SBU (as specified by the USB 3.0 Promoter Group[1]) means "Sideband Use" rather than "Secondary Bus". On some devices, it is used to carry UART; on others, audio. [1]: https://www.usb.org/sites/default/files/USB%20Type-C%20Spec%... (pdf)

Their email address is under the Contact link in the header :)

Re: USB Cheat Sheet (2022)

#44

Post by altairprime »

pxeboot wrote: post #30

I still don't understand why MacBooks support USB4/Thunderbolt 4/5, but NOT USB 3.2 Gen 2x2. So you can get 20-40Gb/s speeds with more expensive external disks, but only 10Gb/s with the cheaper, more commonly available ones that advertise 20Gb/s.

I believe it’s that MacBooks support Thunderbolt primarily and USB only where absolutely necessary beyond what’s coded into one of the TB specs; and I assume TB doesn’t define 3.2x2x2 as part of any TB spec <=5?

Re: USB Cheat Sheet (2022)

#45

Post by jasongill »

floxy wrote: post #43

I don't know what short-distance data communications will be like in 2050, but we know it will be called USB.

USB-G 4.6 SuperSpeed Plus, but the cables will still just be used for charging your random electronics and won't even work for that half the time.

Re: USB Cheat Sheet (2022)

#47

Post by brigade »

sgjohnson wrote: post #32
maxloh wrote: post #11

I once heard that the USB naming is misleading by design so that vendors could still sell older generations accessories they had in stock. The USB-IF just rebrands the old ones to make them sound current. Imagine the following naming: USB 3.0 / USB 3.1 Gen 1 / USB 3.2 Gen 1 -> USB 3 5Gbps USB 3.1 / USB 3.1 Gen 2 / USB 3.2 Gen 2 -> USB 3 10Gbps USB 3.2 Gen 2x2 -> USB 3 20Gbps Isn't that much clearer? I think USB 4 is…

> I think USB 4 is finally going to the right direction. USB 4 is actually going into an even worse direction. USB 4 = Thunderbolt 4, except everything is optional. e.g. USB 4 might not even support DP Alt mode. Thunderbolt 4 always will.

Even backwards compatibility is optional in USB4. There are USB4 devices (SSDs at least) that will not function when connected to USB 3 ports.

Re: USB Cheat Sheet (2022)

#49

Post by QuantumNomad_ »

maxloh wrote: post #11

I once heard that the USB naming is misleading by design so that vendors could still sell older generations accessories they had in stock. The USB-IF just rebrands the old ones to make them sound current. Imagine the following naming: USB 3.0 / USB 3.1 Gen 1 / USB 3.2 Gen 1 -> USB 3 5Gbps USB 3.1 / USB 3.1 Gen 2 / USB 3.2 Gen 2 -> USB 3 10Gbps USB 3.2 Gen 2x2 -> USB 3 20Gbps Isn't that much clearer? I think USB 4 is…

I have a USB hub that I bought recently, that has very nice markings on it that are almost like you say :)

I connects via USB4 to the host, and has the following markings on its ports:

- Power in/USB 10Gbps

- USB 10Gbps

- USB 10Gbps

- 8K HDMI

Pretty happy with this one so far.

Post reply on HN