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M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

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Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#71
Apple seems to lack the connectivity options competing chips offer, as seen with the limit on external screens on some M1 models and these USB options. It's easy to underestimate the amount of work that external connectors need the chip to do in order to work optimally.

It makes sense, of course, as the M1 evolved from a mobile chip with at most one port (USB C if you're lucky) and not a lot of host traffic. I hope Apple fixes these issues soon, or at least acknowledges them. More likely than not Apple will just ignore the problem and tell their customers to buy Thunderbolt devices instead.

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#72

Earlier quoted context omitted.

Why bother reading the article when you can just slam out hot takes? > Cables used included a certified Thunderbolt 4 model, and the USB-C (data) cables provided with the cases. Again, each was verified by establishing SuperSpeed+ 10 Gb/s connections to an Intel Mac.

Because we all know unnamed brand / model “certified” cables with drives that are also unnamed brand / model could surely not be the problem? Edit: I did read the entire article. Like others have said here, it doesn’t match with my experience. But because nothing is clearly specified as to what’s used, the article is useless because nobody can compare to see if their setup is the same or different.

No post body was provided.

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#73
post #60

Earlier quoted context omitted.

FWIW it's actually 500MB theoretical (ideal), because USB uses a 8/10 encoding[0], until 3.1 Gen 2 which switches to a 128/132 encoding[1]. So you have a 5Gb/s physical signal, then a 25% encoding overhead, for a raw data throughput of 537MB/s. Once framing and protocol overhead are taken in account, mid-400s effective is probably a good result. [0] https://en.wikipedia.org/wiki/8b/10b_encoding [1] https://en.wikiped…

What sucks, however, is that you can transfer 1TB to a USB drive correctly, and then finally have a bit-error that spoils the entire transfer and might even corrupt your drive. Happened to me several times during testing on different machines and with different cables and drives (luckily no real data was lost, but USB is now sort of banned from my office for use with external harddrives). Any sane protocol would be a…

Are you sure it's a USB problem and not something else? Did you reduce all possible variables - ie how scientific were you in determining USB was the problem and not something else?

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#74
post #48

Earlier quoted context omitted.

> what in the world could "USB 3.1 Gen 2" possibly mean? Versions are free, why not simply name it "USB 3.2" and make the next one 3.3? USB 3.1 Gen 1 is the straight rebranding of USB 3.0, USB 3.1 Gen 2 is the "original" 3.1, which is 3.0 updated to a 10Gbps signalling rate (from 5), and a more efficient encoding (128/132, versus 8/10). But wait, there's worse! USB 3.2 Gen 1 is the same thing as USB 3.1 Gen 1 USB 3.2…

> USB 3.1 Gen 1 is the straight rebranding of USB 3.0 Why? To solve what exactly? In a sane world, it'd be major.minor, with nothing appended at the end. Allowing marketers to take over everything was such a terrible mistake. At this point I myself just don't differentiate USB versions beyond 3.0. 2.0 is the slow one, 3.0 is the fast one, anything newer is "so fast I won't ever saturate this much bandwidth anyway". T…

> Allowing marketers to take over everything was such a terrible mistake.

I think the USB naming is the result of not using marketers.

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#75
post #6

USB went from being the universal bus, to just being the universal connector. There are never any guarantees that your device (or cable!) actually supports the operation you’re trying

There never was a guarantee that a USB A or micro B port supported USB 2.0 either. There are still tons of keyboards and peripherals out there that run on USB 1.1 in your standard USB 2.0 ports.

The moment they added backwards compatibility, the USB confusion started. That's not a bad thing, the real problems are manufacturers being vague about what they do and do not support and the USB people renaming everything every other year.

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#76

Earlier quoted context omitted.

Because we all know unnamed brand / model “certified” cables with drives that are also unnamed brand / model could surely not be the problem? Edit: I did read the entire article. Like others have said here, it doesn’t match with my experience. But because nothing is clearly specified as to what’s used, the article is useless because nobody can compare to see if their setup is the same or different.

Quoted post unavailable.

Just because it works on an Intel Mac does not mean the cable isn’t the issue! Happy to demonstrate in a live video along with oscilloscope readings to prove it is in fact the cable to blame.

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#77

Apple seems to lack the connectivity options competing chips offer, as seen with the limit on external screens on some M1 models and these USB options. It's easy to underestimate the amount of work that external connectors need the chip to do in order to work optimally. It makes sense, of course, as the M1 evolved from a mobile chip with at most one port (USB C if you're lucky) and not a lot of host traffic. I hope A…

> as seen with the limit on external screens on some M1 models (…) I hope Apple fixes these issues soon

It’s only the base M1 used in the low-end devices that has limited support for external screens. A MBPro with M1 Max can drive 3x6k (DP1.4) plus 1x4k(HDMI2.0). That seems like more than enough for a laptop. Sounds to me like these issues have already been fixed.

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#78

The inability of the USB standards body to stick to a versioning scheme beggars belief: what in the world could "USB 3.1 Gen 2" possibly mean? Versions are free, why not simply name it "USB 3.2" and make the next one 3.3? "Gen 2" strikes me as the "Essay FINAL (final version 2).docx" of standards revisions.

I think the should really just use sha hashes of the standard document, to avoid all this version name issues.

Sadly this might be more user friendly then the current setup.

Even just a bit vector of the capabilities, expressed as a decimal or hex number, would be more comprehensible.

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#79

The inability of the USB standards body to stick to a versioning scheme beggars belief: what in the world could "USB 3.1 Gen 2" possibly mean? Versions are free, why not simply name it "USB 3.2" and make the next one 3.3? "Gen 2" strikes me as the "Essay FINAL (final version 2).docx" of standards revisions.

I think it would be fine IF the higher numbers were universal supersets of previous versions of USB. 'i don't care what this version is it's the highest" seems fair. At least the "universal" aspect applies over time.

It's the apples of the world who seem to be on divergent fork with superior and inferior types of functionality that really disrespect the "universal" moniker... While also ambiguating exactly which USB spec they are even implementing.

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#80
post #50
post #25

Earlier quoted context omitted.

There’s gotta be some lobbying or consulting firm hired by manufacturers that’s using the same strategy between the two standards. The consortiums don’t seem to realize that short-term profits are coming at their expense of their brand.

When you're the only game in town, brand doesn't matter so much.

display port?
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