Very true. Do you think I can plug another Multiport Adapter into the first one's USB-C port?
Actually I just found the answer in the USB 3.1 spec:
"adaptors/cables with a type-C receptacle are not allowed."
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I think I found a way to connect the LED Cinema Display
- Thread starter kenbrinkman
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Very true. Do you think I can plug another Multiport Adapter into the first one's USB-C port?
Actually I just found the answer in the USB 3.1 spec:
"adaptors/cables with a type-C receptacle are not allowed."
ctyrider
macrumors 65816
As long as the USB-C port in the Multiport Adapter is standards-compliant - I don't see why you shouldn't be able to. But not sure what that actually solves. You still end up with a single USB-C port, which can be connected to a wall charger.. but you now have 2x HDMI and 2x USB-A ports.
Which spec are you referring to?
The USB 3.1 developer's specification on usb.org (the standards body), the section on Type-C 1.1. It also specifies a "charge only DFP" (downward facing port) which only source Vbus from the host receptacle, to create a receptacle for charging only. So that seems it is referenced.
Although it is talking about (mostly legacy) adapters, it doesn't seem to mention active hubs (unless I missed that part, it's been almost six months since I read the whole thing). So a large adapter could be an active hub, but putting the USB 2.0 port on something could make it considered a legacy adapter. I think the docks are considered "full featured devices" for the purposes of Type-C receptacles.
But again, not everyone needs to follow the standards!
shenan1982
macrumors 68040
Just because they don't smother the USB logo on a computer doesn't mean a company isn't complying with the standard... FYI
edit: to remove personally identifying information not relevant to the thread, plus response is to an ignored user so I can no longer see the responses.
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JackRegan
macrumors newbie
Blimey, with this amount of leads/adapters and cost, as a stop gap could you attach an Apple TV and air play to it ? At least you could use your lovely display until we start to see some more cables/hubs being released. I'm not sure if this would be an option as I don't own an ACD, its just a thought.
shenan1982
macrumors 68040
Not sure what you're looking at but the spec I'm seeing that the alliance having agreed to doesn't state that in order to comply with the spec it must have the logo for USB-C, nor does it address being printed on or embossed. Not sure what you're even talking about... pc and mac has been making laptops and desktops for years without usb logos... and countless phone manufacturers use the micro-usb spec without so much as a printed logo or anything.
- That wouldn't solve anything, as the Apple TV's only video output is HDMI - just like Apple's Multiport adapter.
And if anyone's interested, it has been confirmed that the USB-C port on the adapter is strictly for charging.
It's a huge mystery to me why Apple has chosen to build an HDMI adapter but not a Mini DisplayPort one. Surely, mDP is far more practical than HDMI, given that mDP can be converted to HDMI very easily...
Does anyone have a guess about their motivations?
ctyrider
macrumors 65816
I wondered about that too.. I think it's probably because there are still a lot of people out there who connect their laptops to TVs and Projectors (especially in business environments). Those don't typically have DP inputs; but just about everything has HDMI inputs.
You are right of course that mDP can be easily converted to HDMI, but that means another dongle on top of an already existing dongle.
Anyway it doesn't bother me that much that Multiport Adapter had HDMI, since it's a proper HDMI v1.4, and it can support the sane high resolutions as DP 1.2.
- Yes, you're probably right. Still, it seems to me a mDP one would have been a better choice. If they didn't want to make three adapters, then they should have just ditched the VGA and let VGA users use an extra adapter...
Not having a mDP severely limits your choices, and it's not like they could have been motivated by increased sales of their HDMI monitors as a result... Basically, you can't use a single Apple display with the MacBook currently while also having it connected to power.
- Though only at 30Hz for UHD. But that doesn't really matter too much, since the MacBook itself can't do more anyway...
ctyrider
macrumors 65816
I am pretty sure Apple doesn't care about compatibility with their LED Cinema displays, which they stopped selling some years ago 🙂
And when it comes to Thinderbolt Displays which they do sell - well, those won't work with either HDMI or mDP ports, so that makes no difference.
- All true. It just seems stupid to me to forgo a great standard like DisplayPort in favour of a far less flexible and less capable (if more widely used) one like HDMI.
"Thinderbolt". 😀
If HDMI 2.0 can do 4k and includes audio, what isn't capable about that? I agree though, it would make it much easier to keep using my Apple Display which is DisplayPort.
- The Multiport adapter isn't using HDMI 2.0...
But if you want to compare HDMI 2.0 with DisplayPort, it should be with DP 1.3, in which case DP is still far more capable than HDMI.
And more flexible, as mentioned, since you can do DP->HDMI but not HDMI->DP (barring active converters).
cmsj
macrumors regular
Realistically, I think you have to wait for a USB Type C dock to appear.
The reasons being:
1. The USB Type C port on the Apple Multiport Adapter is charge only, no data or video is available there (see https://support.apple.com/en-us/HT204360 )
2. USB's DisplayPort support does not pass through hubs, so you would need to be plugging a dock in. The dock may well also offer a hub, but it would have to be aware of the video stream and be splitting it off to a displayport/hdmi port.
The reasons being:
1. The USB Type C port on the Apple Multiport Adapter is charge only, no data or video is available there (see https://support.apple.com/en-us/HT204360 )
2. USB's DisplayPort support does not pass through hubs, so you would need to be plugging a dock in. The dock may well also offer a hub, but it would have to be aware of the video stream and be splitting it off to a displayport/hdmi port.