Isn’t there a change in how USB is represented now? They should now have the max speed and power on the cable/adapter
Comment on The EU common charger : USB-C
MargotRobbie@lemmy.world 8 months ago
Since everyone here seems so confused by USB naming schemes, a short primer:
USB 3.0, 3.1, 3.2, and and USB4 are the major and minor revision number of the standard. You don’t have to worry about it if you are not implementing it yourself.
The Gen number indicates the supported transfer speed, Gen 1 is 5Gbps, Gen 2 is 10, Gen 3 is 20, regardless of the spec revision.
(USB 2.0 is 480mbps)
Dual lane (Gen ?x2) means you take the speed of the Gen number and multiply it by 2.
The only major difference between USB 3 and 4 is that USB4 uses Type C plug only, whereas USB 3 can use a variety of connectors.
All USB-PD compliant cable supports up to 100w of power delivery, only cables labeled as EPR (extended power range) supports up to 240w of power.
SnipingNinja@slrpnk.net 8 months ago
TheGrandNagus@lemmy.world 8 months ago
What the above user is saying is how it’s listed in specs and technical documents
What you are saying is how the USB IF recommends it be marketed. In theory, yours is the only one the average person should worry about
However in the real world it’s an absolute mess of OEMs advertising their ports as being one or the other naming schemes, or neither and just saying “USB”
Aceticon@lemmy.world 8 months ago
Also to add to this, the USB-C connector is perfectly compatible with the actual USB data protocol all the way back to the original USB (1.0) in low speed mode (with its mind-dazzling 1.5Mb/s speed) - all the required pins are still there as are the bits of electrical signalling necessary in the original USB protocol.
It’s just that USB-C adds more data lines and other things used in the more modern versions of the USB protocols (including for the newer power protocol - USB-PD, though maintaining backwards compatibility with the old power provision which was controlled via the USB data protocol itself) as well as support for the connector being flippable (works whatever way you plug it in) which is done by basically having the original lines appear twice, one on each side of the connector.
pajn@lemmy.blahaj.zone 8 months ago
Isn’t standard USB C cables only 3A (60W)? And 5A (100W) only if they identify themselves with a built in chip?
MargotRobbie@lemmy.world 8 months ago
Hence, the “USB-PD compliant” portion, which partly is that tiny controller chip.
You can technically have USB-C to C cables that are not PD compliant, but these are not the cables you want to be buying.
mikey@sh.itjust.works 8 months ago
Also, USB4 can optionally support PCIe tunneling, which is a fancy way of saying it supports plugging more advanced types of hardware in (like GPUs, high-speed network cards or NVMe SSDs) at speeds of up to 40Gbps.
And there is USB4 v2 (not kidding, that’s the name) which extends USB4 to up to 80Gbps, but there are no devices that support that yet.
Pinecone@lemmy.world 8 months ago
To make it even more confusing, USB 4 and its subsequent versions are basically adapting more and more Thunderbolt features.