USB4 Specification Announced: Adopting Thunderbolt 3 Protocol for 40 Gbps USB • Hacker News Board

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

#51

Post by monocasa » Mon, Mar 04, 2019, 9:04 PM UTC

artiscode wrote: post #36

koala_man wrote: post #27

tl;dr: Intel made Thunderbolt 3 royalty free in 2018, so now it's essentially being adopted as USB4. I had to look up what the point of 40Gbps was, and the industry evangelization site https://thunderbolttechnology.net/ explains that it will allow driving one 5k display or two 4k displays, which is not possible with the 20Gbps offered by USB 3.2 or Thunderbolt 2. This also helps external GPUs, where TB2/USB3.2 is the…

Does 40Gbps mean two 4K displays daisy chained?

Yeah. One 4k60 screen is between five and six gbps.

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

#52

Post by wlesieutre » Mon, Mar 04, 2019, 9:04 PM UTC

walterbell wrote: post #25

jsgo wrote: post #19

Earlier quoted context omitted.

or port color. We've used blue and red at least, guess it is time for green (in which case, confusion for the Razer Blade users).

we use yellow for power/charging

Yellow IIRC means "provides power even when the computer is sleeping."

It'd be harder to do markings like this on USB-C ports though. They don't have a big visible chunk of plastic in the middle.

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

#53

Post by monocasa » Mon, Mar 04, 2019, 9:05 PM UTC

alacombe wrote: post #37

This is a poisoned gift, there was a twitter conversation posted a couple weeks ago about the cluterf*ck that thunderbolt is... quite a scary read :-/ https://twitter.com/whitequark/status/1097777102563074048

Honestly, most of this addresses that, by opening the spec and getting rid of royalties.

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

#54

Post by [deleted] » Mon, Mar 04, 2019, 9:05 PM UTC

mac01021 wrote: post #39

nintendo1889 wrote: post #34

I am starting to see computers with USB C on the host side. The future of one single connector to rule them all will be here soon. Wait a minute, we already had that, it was usb 2.0?!?!

I never saw anyone hooking up a monitor via USB 2.0

[deleted]

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

#55

Post by int_19h » Mon, Mar 04, 2019, 9:05 PM UTC

nintendo1889 wrote: post #34

I am starting to see computers with USB C on the host side. The future of one single connector to rule them all will be here soon. Wait a minute, we already had that, it was usb 2.0?!?!

For me the true killer feature of USB-C is charging everything. Finally, a single charger for the laptop, the tablet, the phone, the router etc.

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

#56

Post by DaiPlusPlus » Mon, Mar 04, 2019, 9:05 PM UTC

reaperducer wrote: post #41

mac01021 wrote: post #39

Earlier quoted context omitted.

I never saw anyone hooking up a monitor via USB 2.0

I've seen them for sale on Amazon and elsewhere. I always thought they'd be neat to throw in a supplemental kit bag for a second display on the go. I think some of the smaller ones were even bus powered.

Those are USB 3.0-based DisplayLink connectors.

Any supposed USB 2.0-based display connectors (I’ve never seen any, I’m just speculating) would have been some VNC-like contraption involving an emulated frame buffer on the host.

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

#57

Post by _wmd » Mon, Mar 04, 2019, 9:06 PM UTC

chrisseaton wrote: post #48

pkaye wrote: post #18

Earlier quoted context omitted.

I'm no means an expert but up to USB 2.0 there were 4 pins (2 for power and 2 differential signals for bidirectional data) With USB 3.0 they added 4 more signals for separate transmit/receive. Initially they used 8b/10b encoding and then switched to 128b/132b encoding. They also increased the signaling rate with each generation. Also in the USB 2.0 and earlier the higher level protocols were kind of inefficient with…

> With USB 3.0 they added 4 more signals for separate transmit/receive So is it not actually serial any more?

Transmit and receive previously shared pins, USB 3 split transmit and receive into separate pairs, which are still serial

edit: yikes, looks like USB C doubled the number of those separate pairs, for a total of 6 data pins (2x RX, 2x TX, 2x USB 2.0 RX/TX)

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

#58

Post by DaiPlusPlus » Mon, Mar 04, 2019, 9:06 PM UTC

781 wrote: post #22

MichailP wrote: post #9

Does this also mean that soon every computer will be making noise/radiating waves around 40GHz? Can someone with more depth in this area shine some light on this?

PCI Express is already working at those data rates.

Computer cases are electrically insulated.

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

#59

Post by gumby » Mon, Mar 04, 2019, 9:06 PM UTC

artiscode wrote: post #46

Honestly, I'm waiting for old USB(USB A, USB B) to be deprecated and USB C become the new universal USB. As in ATM machine, you get the drill. Current USB cable situation is a mess - my phone is USB C, but it came with a USB A to USB C cable. Good thing I can connect it to my 2017 MacbookPro using it's original USB C charging cable! However then I can't charge. Sometimes I use a USB C to female USB A dongle to use my…

> good USB C cables seem to be made out of gold

USB type C cables are active (they have silicon in them and handshake themselves with the host rather than simply being wire (possibly plus a resistor) as with old USB cables.)

Cost will come down as volume goes up. Currently the only way to buy a cheaper cable is to buy a noncompliant and possibly dangerous one.

> Life would become so much easier if everything was USB C to USB C

I would agree with the added caveat of "... and if you could tell by inspection what sort of cable you have: speed, power, and protocols supported -- and some way to verify conformance"

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

#60

Post by nintendo1889 » Mon, Mar 04, 2019, 9:06 PM UTC

DaiPlusPlus wrote: post #42

nintendo1889 wrote: post #34

I am starting to see computers with USB C on the host side. The future of one single connector to rule them all will be here soon. Wait a minute, we already had that, it was usb 2.0?!?!

USB-A/B for USB2.0 lacked the pin-count to provide compatibility with other connector standards by using a passive adaptor (except a few like PS/2). It also lacked the data bandwidth to encapsulate many other connector electrical protocols when using an active adapter except a few like RS-232 and 100mbps Ethernet. It also couldn’t deliver much power either - 500mA at 12V is only 2.5W - enough for a mouse or webcam.

True, I just realized that this is for display bandwidth. And also in the future, possibly for inexpensive 40gbps networking/video/gpu