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scarface74

Yes because USB C is so user friendly:

Grab a random USB C cable, now answer a few questions

- how much power can it deliver?

- how much data can it deliver?

- can it deliver video over USB?

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For any usb-c cable in my house, the answer to all those questions is, in order:

- enough to charge my airpods

So you have AirPods and no other Apple devices?

And people hoping that Apple’s move to USB C will mean USB3 speeds need to look no further than the latest low end iPad that has USB C. But transfers data at USB 2 speeds. The same happened on many low end to midrange Android phones.

On a low end iPad very few people have a need for any devices to connect to it via usb, even fewer than would benefit from usb3 speeds.

You mean an A14 iPad? That’s not exactly slow by any means and the newest A15s that come in the phones are not appreciably faster.

I didn't say it was slow. I said on low end iPads people dont typically have a need to connect things to its USB, certainly nothing that would have any benefit from USB 3.

A low end iPad with an A14 is hardware wise more capable and definitely more responsive than many low end consumer PCs that are sold today. For instance it is more than capable of editing music and video that you may want to transfer to or from a computer or an external hard drive.

> And people hoping that Apple’s move to USB C will mean USB3 speeds... than the latest low end iPad

Who is expecting anything out of the low end iPad for anything other than taking notes or watching videos? The new high-end iPads are thunderbolt and USB4.

But more importantly... so? What does this have to do with charging AirPods?

Basically no cables that are USB-C and more than 0.5 meters support charging AND video/high-speed. Unfortunately, I think people just have to accept that there's "data cables" and "PD cables" and "junk short cheap cables that don't do anything". You can spend like $150 buying multi-meter thunderbolt/USB-IF cables that support PD + full data and full video, or just buy two cables.

I have these

https://www.amazon.com/dp/B093YVRHMB?ref=ppx_pop_mob_ap_shar...

The low end iPads come with an A14. That’s not exactly a slouch and has the keyboard accessories

No, I've also got a MacBook. And in my life, this supposed flaw in USB-C just doesn't exist. I have yet to experience a USB-C cable that doesn't do what I expect it to. But perhaps that is because I don't have unreasonable expectations, like the shape of the hole I plug a wire into making data transfer speeds faster

Video over USB C is a standard and supported by Macs and high end iPads.

My favorite is USB-C devices that only charge with A to C cables, not C to C cables.

I forgot to mention those. Some devices don’t support USB PD and you have to use USB A to USB cables.

That's why my stupid flashlight won't charge on some chargers! Thank you, you've solved a mystery for me.

> won't charge on some chargers

To add more detail, USB-PD (power delivery) is a complex negotiated protocol. The charger is supposed to output some meager 5v power supply like a traditional USB A supply, and the device asks for some specific voltage, and the charger tells the device if it can do that, and then does it (up to 24v, iirc). PD Chargers are supposed to support any of the supported voltages, but many (eg. Apple MacBook Chargers) only support a subset of the voltages.

By spec USB-C chargers don't even provide 5V without a pulldown resistor on the CC lines. It's safe to connect two compliant USB-C charges together.

How does USB A deliver power differently such that it works with devices which don’t support USB PD?

With USB C, is the power delivery on a pin these devices don’t have? Then the pin USB A would use to send power isn’t present with USB C (either physically or on purpose)?

USB-C allows a certain pin to be used for PD negotiation. USB-A doesn't have this pin. USB-A to USB-C cables have a fixed resistor pulling this pin to signal which power requirements they support.

Badly designed devices do not negotiate power requirements and just start drawing power, which doesn't work with proper USB-C cables (which expect to negotiate first) but obviously works with USB-A to USB-C cables (which always support the same power requirements)

Thanks for the explanation. This explains all the weird behaviour of devices I have which don’t charge (or charge poorly) over USB C. This was so confusing because I assumed that they should work fine given that they have USB C ports, but no… I’ll have to keep some USB A to C cords around for years still.

I just bought a CalDigit element hub and had some hesitation because I thought “how long will I really need the USB A ports?” Evidently they will be handy for quite a while.

> How does USB A deliver power differently such that it works with devices which don’t support USB PD?

USB A devices (and by extension, USB A to USB C cables) always delivers power. USB C devices only deliver power once they see a specific resistor to ground on a control pin. If the device is missing that resistor (actually a pair of resistors, one for each side of the cable), a USB C device on the end of a USB C to USB C cable won't provide power.

(Preemptive nitpicking: actually, USB C devices provide a bit of power in that control pin, which is how they detect that resistor to ground; but that's separate from the main power pins.)

That is a design defect. The USB-C spec requires C-C charging so if it has a USB-C port and won't charge with a C-C cable it is defective. Return it and tell them why. I have done this a few times.

I've got two types of USB-C cables at home:

2m long 100W PD 5Gbit/s cables 40cm long TB3 cables

Super easy to find, super easy to remember. And all of them already have the new wattage/data rate labels.

Somehow I don’t think any of these are an issue for AirPods

What’s the use of a “universal cable” that doesn’t work everywhere even though it should?

The way I had it explained to me is that “Type C” is the form factor, and that’s what is meant by universal. Which actual USB standard is implemented by the client/host varies widely.

This leads to an immense amount of confusion because people are used to different form factors indicating compatibility.

And the corollary is: What is the advantage of a universal form factor if the wire protocols are different?

If the wire protocols are different, then an identical form factor is a hindrance, not an advantage.

I'd much rather have it this way than how it was before. Sure, there are headaches, but not more than in the thirty-adapter-bag before times, and now if you get a nice cable that supports thunderbolt/usb3.14159/etc. it really can do everything.

Of course. Simple solution to all people yelling and complaining their 2$ amazon usb cable is not top notch compared to 50$ apple one is - don't buy cheap crap.

There are good usb cables that handle it all, still cost fraction of apple ones due to simple effect of competition, and are more durable. But quality comes at a cost, just you don't need to pay apple profit margins.

I find the USB-C headaches worse. With a bag of cables if the cable fits[1] it works to the full capability of the device. If I'm traveling and forgot something I can expect that the cheapest gas station cable or a borrowed cable will work.

With USB-C I have to spend good money for every every cable in order to ensure that any cable I grab from my bag works. And these cables are going to be so thick that they are annoying to use with a mouse or keyboard.

I can rearrange my office and use a cheap 5 meter usb-A to B cable to get to where the printer is now (true story). If I want a 5 meter usb-C to C cable for data I need to spend over $300.

[1] excluding all the possibilities of chargers with incompatible DC barrel plugs, which is generally true of the time frames we're talking about

If you use a lot of wired devices I guess I can see that being a headache. I use wireless peripherals and make sure they're all usb-c, so when I travel I only need to remember one cable, maybe another as backup. These problems also improve as USB-C becomes more mass-manufactured. Case in point: now there's a 5 meter USB-IF certified usb-c power/ data cable at the top of the Amazon results for $19.

It’s worse than that though because what’s implemented by the host and client can be the same but the cable can be incompatible too.

usb-c is basically a standardized oval.

> The way I had it explained to me is that “Type C” is the form factor, and that’s what is meant by universal. Which actual USB standard is implemented by the client/host varies widely.

There's also a couple of universal USB standards: every client/host is supposed to implement USB 2.0, unless they're charging-only; and every client/host is supposed to implement simple power delivery (negotiated through resistor values) at 5V and at least 500mA (for a USB-A 2.0 to USB-C cable, other combinations are supposed to deliver more current).

- when was the last time I had to scrape pocket lint out of the gaps?

- am I due for another?

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