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USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

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Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#221

Post by kkarakk »

stordoff wrote: post #219
notJim wrote: post #159

Earlier quoted context omitted.

It's not fast enough. USB cannot drive a 4k monitor at 60hz. You can use the physical interface to do it, but this uses Thunderbolt. This means that the dream of a one-cable-for-everything setup is not here yet, unless you use a Thunderbolt dock, which multiplexes the USB stuff in with the monitor signal. A thunderbolt dock costs around 10x more than a simple USB dock.

To be honest, I'm not really sure why this is necessary. I don't see why couldn't have two interfaces - one simple/moderate-speed one for most use cases, and a fast one (which could incorporate the slower one) for when it's needed. Trying to cram everything into one interface seems to introduce too many compromises (I no longer know what the port does) and a lot of complexity.

the point is you shouldn't have to know what the port does, it should seamlessly interconnect. you shouldn't have to be thinking about wires etc. it's like how bluetooth somewhat seamlessly interconnects across generations of bluetooth. that's how all standards should be

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#222

Post by jabl »

gumby wrote: post #207
dcbadacd wrote: post #175

Earlier quoted context omitted.

There's also the Nintendo Switch issue

That was due to non-compliance on Nintendo's part, hardly a USB Type C issue.

If the spec is so complex even a relatively big and stable corp like Nintendo can't get it right, well, maybe the spec is (partly) to blame?

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#223

Post by tempestn »

p1mrx wrote: post #220
userbinator wrote: post #177

Earlier quoted context omitted.

The only way you can make a specification like USB "universal" is for parts of it to be optional. No one is going to build a USB mouse with a 40Gbit link speed, for example.

What if it's a high DPI gaming mouse?

Even if there were some hypothetical mouse that needed that kind of speed (there isn't[1]), it's irrelevant to your parent's actual point.

[1] https://www.howtogeek.com/193866/are-there-any-benefits-from...

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#224

Post by [deleted] »

mjevans wrote: post #142
sneak wrote: post #127

Earlier quoted context omitted.

Why is that? You can't do that from looking at a file with an unknown extension. Physical connector technology and signaling protocol are entirely different things. I'd be fine with literally everything using the same physical connector, but knowing that I can't and shouldn't plug my 5VDC battery-charger into a 110VAC outlet. I still have speakers that are connected by stripping a lampcord pair with my teeth, pushing…

Pick any random USB-C cable. Can you tell by looking at it what speeds it supports? Is it USB-3 or USB-2? How about the power delivery aspect, how much power is it cable of transferring? You might be able to tell some of those things from modern cables, if they're bragging about a speed factor, but otherwise it isn't clear.

[deleted]

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#225

Post by sneak »

mjevans wrote: post #142
sneak wrote: post #127

Earlier quoted context omitted.

Why is that? You can't do that from looking at a file with an unknown extension. Physical connector technology and signaling protocol are entirely different things. I'd be fine with literally everything using the same physical connector, but knowing that I can't and shouldn't plug my 5VDC battery-charger into a 110VAC outlet. I still have speakers that are connected by stripping a lampcord pair with my teeth, pushing…

Pick any random USB-C cable. Can you tell by looking at it what speeds it supports? Is it USB-3 or USB-2? How about the power delivery aspect, how much power is it cable of transferring? You might be able to tell some of those things from modern cables, if they're bragging about a speed factor, but otherwise it isn't clear.

Pick any random cable, regardless of what’s on the ends.

Yes, I can determine what it is used for, because I bought it for a purpose. What you are describing is the same issue with barrel-style AC or DC wall warts, and those powered the world for a few decades just fine.

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#226

Post by johncolanduoni »

WhitneyLand wrote: post #210
_wmd wrote: post #195

Earlier quoted context omitted.

If only it were just about cost, comprehensiveness might be a better way to look at it. I really don't want my laptop's keyboard and trackpad to require clocks to drive my clicks and keystrokes at 40Gbps, that's just going to murder batteries and bank accounts for no reason whatsoever. So you're left with a choice in this wonderful alternative non-optional world: some expensive temperature controlled oscillator with…

Not sure you're countering my argument at all because I of course agree we can't just blindly do things that make systems impractical to buy or use. If fact I would certainly be all for a few basic well thought out combinations as mentioned: >> one thing with nothing optional (or at least a very small number of combinations) The problem is, that's not what USB-C/USB-3 whatever is. It's permutations must be in the mil…

What are the degrees of freedom in the spec that are resulting in millions of permutations of optional features?

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#227

Post by throwaway2048 »

jsgo wrote: post #14
penagwin wrote: post #8

Here's an idea, let's make different connector shapes depending on the cable/connector's capabilities, lets do one for connectors that support display, one for power, one for thunderbolt, that way they're easy for the average consumer to identify! Oh wait that's the issue USB was supposed to solve in the first place....

My hope is that Type-C is going to be all of those things so that in the future, I only need one kind of cable (until the inevitable new plug that supplants it, but hopefully universally used as well). Currently, I have to pay attention to a USB3 Type-C cable vs a Thunderbolt 3 cable as there is a difference (I was shopping for a long TB3 cable and was unable to find one. Instead, seems the longer ones tend to be USB…

Its not going to happen in the future either, There is never going to be a desktop motherboard that delivers full spec (100W) USB3 power delivery to say, 6 ports at once, or a laptop even capable of delivering to 1.

The USB spec is too ambitious and its inevitable that some use cases are mutually incompatible.

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#228

Post by johncolanduoni »

jabl wrote: post #222
gumby wrote: post #207

Earlier quoted context omitted.

That was due to non-compliance on Nintendo's part, hardly a USB Type C issue.

If the spec is so complex even a relatively big and stable corp like Nintendo can't get it right, well, maybe the spec is (partly) to blame?

Are there any widely used hardware specs that a "big and stable" corp hasn't gotten wrong in some implementation? Back when Ethernet was a lot simpler than it is now there were plenty of big players who couldn't even manage to provide unique MAC addresses. Is IEEE754 being too complex to blame for Intel's FDIV bug?

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#229

Post by xorfish »

WhitneyLand wrote: post #124

What's optional? That's the most important thing to know is what's optional in the spec. That could make it great or a major pain. I'm referring to how many features the specification defines as "optional" for manufactures and that the USB organization requires for logos. This is why even USB-C is a nightmare. Consider a USB-C cable or device port. It could be charge only, data only, monitor support. There are even m…

USB-A can be 1.1, 2.0, 3.0, 3.1 Gen 1, 3.1 Gen 2.

Same for USB-C. It is just a standardized connector with a defined pinout.

If you force the standard to always provide 15 watt, then how will you do that on phones or a raspberry pi or other low power devices? If you force SuperSpeed or SuperSpeed+ over the connector then you won't see it on budget or midrange phones.

It makes perfect sense to differentiate between the supported protocols and the connector itself. Otherwise you would need a ton of different connectors that you may never need on your device.

Re: USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB

#230

Post by wongarsu »

p1mrx wrote: post #220
userbinator wrote: post #177

Earlier quoted context omitted.

The only way you can make a specification like USB "universal" is for parts of it to be optional. No one is going to build a USB mouse with a 40Gbit link speed, for example.

What if it's a high DPI gaming mouse?

Back-of-the-envelope calculation: if you send a 100 byte status update 100,000 times per second, that's just 80 Mbits/s.

To saturate a 40Gbit/s link you could send a 1kB update every 200 nanoseconds (that's 5MHz), assuming perfect efficiency.

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