11 ms·

Thought experiment: grab a random “standard” USB C cable and answer a few questions: - will it charge my MacBook Pro 16” and deliver the full 100W? - will it

Thought experiment: grab a random “standard” USB C cable and answer a few questions: - will it charge my MacBook Pro 16” and deliver the full 100W? - will it supply data and if so, at what speed? - can it deliver power and video over USB C and work with my portable secondary display?

sovnade 4y ago
the problem is that there is no "standard" usb-c cable. there's usb 3.0, usb 3.1, usb 3.2, usb 3.2 gen 2, usb-c thunderbolt, etc. this is a major problem they need to figure out imo. edit: or move to a new major version (usb 4.0) and make all new cables do all of that so if you get a 4.0 cable, you know you can use it for everything at once. i have no idea if this is currently the plan or not.
- scarface74 4y ago
  Obligatory: https://xkcd.com/927/ https://xkcd.com/927/
  - sovnade 4y ago
    hah, i didn't say it was a simple problem to solve :)
- Vt71fcAqt7 4y ago
  >or move to a new major version (usb 4.0) They're already at USB4 version 2.0
seba_dos1 4y ago
> - will it charge my MacBook Pro 16” and deliver the full 100W? If it's e-marked, then yes. > - will it supply data and if so, at what speed? > - can it deliver power and video over USB C and work with my portable secondary display? If it's not just a USB 2.0 cable, then yes.
- scarface74 4y ago
  These aren’t rhetorical questions. I didn’t start looking into USB until two years ago when I got a work MacBook. Before then, it had been almost a decade and a half since I had a Mac. - the USB C cable that came with the x86 Macs and most USB C charging cables are power only and don’t support data - many USB C cables that do support data only support data at USB2 speeds and don’t support video over USB - I think some cables can support video over USB C. But only support data at lower speeds than 10Gbps.
  - megous 4y ago
    Yeah, no. There are no non-data Type-C cable assemblies. If you have a C-C cable without at least USB 2.0 data signals wired through, it's not standards compliant: https://megous.com/dl/tmp/6e4e502cb9f6e709.png https://megous.com/dl/tmp/6e4e502cb9f6e709.png
    - scarface74 4y ago
      The USB C cable that comes with the MacBook Pro only supports charging https://www.macintoshhowto.com/hardware/why-your-usb-c-cable-may-not-work-to-connect-your-macbooks-together.html https://www.macintoshhowto.com/hardware/why-your-usb-c-cable...
      - seba_dos1 4y ago
        It only pretends to be a USB-C cable then.
        seba_dos1 4y ago
        Actually, scratch that (can't edit anymore) - looking closer at what you linked to, this appears to be a perfectly fine, data-capable USB 2.0 cable. It's just not a fully featured cable capable of Thunderbolt, and connecting two Macbooks is a feature that relies on Thunderbolt and doesn't work over USB. So, it's just like I said in my initial reply. Really, unless you need to get the highest bandwidth available from latest USB standards, it's not that complicated at all. In most non-Thunderbolt cases, all you need to know is whether your cable is USB 2.0 only or not - and Thunderbolt cables tend to be obviously marked as such.
altairprime 4y ago
There are four different versions and a wide variety of power choices that each “USB C” cable is permitted to make. So the answer to your question is “it depends”, since 100W support is optional in USB-C cables. (Note: If you change “USB C” cable to “Thunderbolt 3” cable, those choices are all zeroed out. So the answer to that modified question is “yes”, since 100W support is mandatory in Thunderbolt 3 cables.) This will get better over the next year for certified cables that print USB-compliant logos on them, with the end of SuperSpeed branding: https://news.ycombinator.com/item?id=33034530 https://news.ycombinator.com/item?id=33034530 > Branding for certified USB Type-C cables is also being updated. Rather than simply listing their data transfer speeds, cables will also (for the most part) have to list the charging wattage they’re capable of carrying. So a cable can’t just be branded as being a 40Gbps cable as with last year’s guidelines, it’ll now also have to list a charging speed like 60W or 240W. But I’ve never seen the USB logos printed on a cable before, so it remains to be seen whether the reduction in complexity to Gbps/W only is sufficient to persuade cable makers to certify their cables or not.

sovnade 4y ago

the problem is that there is no "standard" usb-c cable. there's usb 3.0, usb 3.1, usb 3.2, usb 3.2 gen 2, usb-c thunderbolt, etc. this is a major problem they need to figure out imo. edit: or move to a new major version (usb 4.0) and make all new cables do all of that so if you get a 4.0 cable, you know you can use it for everything at once. i have no idea if this is currently the plan or not.

scarface74 4y ago
Obligatory: https://xkcd.com/927/ https://xkcd.com/927/
- sovnade 4y ago
  hah, i didn't say it was a simple problem to solve :)
Vt71fcAqt7 4y ago
>or move to a new major version (usb 4.0) They're already at USB4 version 2.0

seba_dos1 4y ago

> - will it charge my MacBook Pro 16” and deliver the full 100W? If it's e-marked, then yes. > - will it supply data and if so, at what speed? > - can it deliver power and video over USB C and work with my portable secondary display? If it's not just a USB 2.0 cable, then yes.

scarface74 4y ago
These aren’t rhetorical questions. I didn’t start looking into USB until two years ago when I got a work MacBook. Before then, it had been almost a decade and a half since I had a Mac. - the USB C cable that came with the x86 Macs and most USB C charging cables are power only and don’t support data - many USB C cables that do support data only support data at USB2 speeds and don’t support video over USB - I think some cables can support video over USB C. But only support data at lower speeds than 10Gbps.
- megous 4y ago
  Yeah, no. There are no non-data Type-C cable assemblies. If you have a C-C cable without at least USB 2.0 data signals wired through, it's not standards compliant: https://megous.com/dl/tmp/6e4e502cb9f6e709.png https://megous.com/dl/tmp/6e4e502cb9f6e709.png
  - scarface74 4y ago
    The USB C cable that comes with the MacBook Pro only supports charging https://www.macintoshhowto.com/hardware/why-your-usb-c-cable-may-not-work-to-connect-your-macbooks-together.html https://www.macintoshhowto.com/hardware/why-your-usb-c-cable...
    - seba_dos1 4y ago
      It only pretends to be a USB-C cable then.
      - seba_dos1 4y ago
        Actually, scratch that (can't edit anymore) - looking closer at what you linked to, this appears to be a perfectly fine, data-capable USB 2.0 cable. It's just not a fully featured cable capable of Thunderbolt, and connecting two Macbooks is a feature that relies on Thunderbolt and doesn't work over USB. So, it's just like I said in my initial reply. Really, unless you need to get the highest bandwidth available from latest USB standards, it's not that complicated at all. In most non-Thunderbolt cases, all you need to know is whether your cable is USB 2.0 only or not - and Thunderbolt cables tend to be obviously marked as such.

altairprime 4y ago

There are four different versions and a wide variety of power choices that each “USB C” cable is permitted to make. So the answer to your question is “it depends”, since 100W support is optional in USB-C cables. (Note: If you change “USB C” cable to “Thunderbolt 3” cable, those choices are all zeroed out. So the answer to that modified question is “yes”, since 100W support is mandatory in Thunderbolt 3 cables.) This will get better over the next year for certified cables that print USB-compliant logos on them, with the end of SuperSpeed branding: https://news.ycombinator.com/item?id=33034530 https://news.ycombinator.com/item?id=33034530 > Branding for certified USB Type-C cables is also being updated. Rather than simply listing their data transfer speeds, cables will also (for the most part) have to list the charging wattage they’re capable of carrying. So a cable can’t just be branded as being a 40Gbps cable as with last year’s guidelines, it’ll now also have to list a charging speed like 60W or 240W. But I’ve never seen the USB logos printed on a cable before, so it remains to be seen whether the reduction in complexity to Gbps/W only is sufficient to persuade cable makers to certify their cables or not.