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ACE: Apple Type-C Port Controller Secrets

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Re: ACE: Apple Type-C Port Controller Secrets

#61

Post by joshspankit »

breakfastduck wrote: post #47
bluejekyll wrote: post #41

Earlier quoted context omitted.

Yes, Apple seems to be very confused in this regard. They’ve committed to USB-C for all of their computers, but then are continuing to push lightning for all the other portable devices. It’s hard not to be annoyed at them about this. Enough to not buy Apple again? No, not yet, but I’d be lying if it’s not a reason why I’ve delayed purchasing a new device. It leaves a bad taste in my mouth, and makes me grumpy. So I’l…

I think they're keeping lightening to help their 'eco' brand. They just removed chargers from the iPhone box because 'everyone has one' - if they suddenly changed to USB-C on iPhone it would create a LOT of ewaste. I still think they should switch, but I reckon it's because they'd get accused of hypocrisy if they deprecated it.

They could just as easily spin it as “Now you can use the charger from your macbook, meaning only one cable!”

Or, if they want to get really wild: they can openly talk about the other usb-c devices that you might have.

Re: ACE: Apple Type-C Port Controller Secrets

#62

Post by throwaway9870 »

amelius wrote: post #44
xg15 wrote: post #27

Apart from the processors, I'm amazed/bewildered that USB is now complex enough, that the power component of it has its own serial communication protocol (USB-PD), which also has a vendor registry and is extensible with proprietary messages - and by the looks of it, is already in widespread use for all sorts of things that have nothing to do with power delivery. Isn't this sort of reinventing USB on top of USB?

And it still hasn't got error correction?

The problem is that with short haul serial links there is a very small operating range where error correction works. Basically the difference between a working link (very low BER) and a link where even ECC is broken (high BER) is quiet small and adding ECC overhead is deemed an overall loss. These links have quite different characteristics from long-haul links that are dominated by ISI. One way to see this is to look at a waterfall plot and note how steep it is on short interconnects. There is a very small range between working fine and completely broken.

Re: ACE: Apple Type-C Port Controller Secrets

#63

Post by eplanit »

swiley wrote: post #45
xg15 wrote: post #27

Apart from the processors, I'm amazed/bewildered that USB is now complex enough, that the power component of it has its own serial communication protocol (USB-PD), which also has a vendor registry and is extensible with proprietary messages - and by the looks of it, is already in widespread use for all sorts of things that have nothing to do with power delivery. Isn't this sort of reinventing USB on top of USB?

I remember thinking USB2.0 was over complicated, this is absolutely insane.

It was, and this is. You were right.

Re: ACE: Apple Type-C Port Controller Secrets

#64

Post by joshspankit »

meragrin_ wrote: post #57
Ellipsis753 wrote: post #52

Earlier quoted context omitted.

It does. (Checksums)

Aren't checksums for error detection and not error correction? As I understand it, error correction is having enough information to correct the error while error detection is only knowing an error has occurred.

reed-solomon is most likely used here. It’s the tech in CDs and ECC RAM. Checksums that also have enough data for recovery.

Re: ACE: Apple Type-C Port Controller Secrets

#65

Post by bluejekyll »

robin_reala wrote: post #43
bluejekyll wrote: post #41

Earlier quoted context omitted.

Yes, Apple seems to be very confused in this regard. They’ve committed to USB-C for all of their computers, but then are continuing to push lightning for all the other portable devices. It’s hard not to be annoyed at them about this. Enough to not buy Apple again? No, not yet, but I’d be lying if it’s not a reason why I’ve delayed purchasing a new device. It leaves a bad taste in my mouth, and makes me grumpy. So I’l…

Not for all their portable devices; the iPad Pros have been USB-C since 2018, and the iPad Air since September this year.

Ah, thanks. I actually totally forgot about. Maybe I should get one now (2 years later) to help spur them on.

Re: ACE: Apple Type-C Port Controller Secrets

#66

Post by bluejekyll »

eru wrote: post #46
bluejekyll wrote: post #41

Earlier quoted context omitted.

Yes, Apple seems to be very confused in this regard. They’ve committed to USB-C for all of their computers, but then are continuing to push lightning for all the other portable devices. It’s hard not to be annoyed at them about this. Enough to not buy Apple again? No, not yet, but I’d be lying if it’s not a reason why I’ve delayed purchasing a new device. It leaves a bad taste in my mouth, and makes me grumpy. So I’l…

I can charge my Switch on random USB-C power sources. (No clue whether it's as effective as the included charger, but certainly works well enough.)

That’s good to hear? I think I was seeing issues with that on some of my chargers, maybe I need to double check the power ratings on the bricks.

Re: ACE: Apple Type-C Port Controller Secrets

#67

Post by s_gourichon »

lmilcin wrote: post #9
bb123 wrote: post #7

Earlier quoted context omitted.

This fascinates me. Is there a website anywhere that is collecting these sorts of use cases? It seems truly mind blowing something as simple as an electric toothbrush would have a processor in it.

Nothing mind blowing. Processor is cheaper than building analog circuitry. Think about your toothbrush. All important timing parameters are configured digitally and you can easily change it. You can technically do the same with resonators but it would take much more board space, be less precise, require inductors which you want to avoid in the circuit, etc.

> important timing parameter

You can also, well, use a regular toothbrush. What is actually important in a toothbrush has nothing to do with electronics.

Re: ACE: Apple Type-C Port Controller Secrets

#68

Post by alexhutcheson »

lmilcin wrote: post #8
ChuckNorris89 wrote: post #4

Earlier quoted context omitted.

Pretty much every microSD card has had an ARM cpu core in it since forever. The Bluetooth radio chip in your phone and the RF chip in your car's key fob already have multicore CPUs inside. Even your optical mouse has a multicore CPU in it to handle image processing and translate the optical feed into motion packaged into USB HID frames. Your fast phone charger has a CPU in it to monitor and negociate power delivery t…

I am right now making backlight with RGB LEDs for my monitors. It is going to have Cortex-M4 ARM in it. I put into just about everything I build these days regardless of how small it is.

Is there a specific dev board with a Cortex-M4 that you like to use, or does it vary by project?

Re: ACE: Apple Type-C Port Controller Secrets

#69

Post by mhh__ »

frederikvs wrote: post #24
Roritharr wrote: post #2

Once again i'm amazed what ALSO has a processor in it. I'm wondering if at some point I'll just see it as normal that nearly every device, no matter how static it may seem, has more processing power than my first computer.

Another thing to consider : more and more single-use items also have processors and electronics in them. At what point will disposable electronics have more processing power than, say, the Apollo flight computer? A couple of examples that I've noticed : There's a sports good store near here where they attach some form of RFID tag to each item (including individual protein bars), to automate the scanning. That means t…

> At what point will disposable electronics have more processing power than, say, the Apollo flight computer?

Already way way way way past that point. There's an article that does the rounds on here about it, but I can't remember the name.

Re: ACE: Apple Type-C Port Controller Secrets

#70

Post by cesarb »

xg15 wrote: post #27

Apart from the processors, I'm amazed/bewildered that USB is now complex enough, that the power component of it has its own serial communication protocol (USB-PD), which also has a vendor registry and is extensible with proprietary messages - and by the looks of it, is already in widespread use for all sorts of things that have nothing to do with power delivery. Isn't this sort of reinventing USB on top of USB?

> Isn't this sort of reinventing USB on top of USB?

It's not on top of USB, it's a completely independent side-channel. And it cannot be on top of USB, since its second main use (besides negotiating the voltage and current in the main power pins) is to negotiate the alternate modes used for the pins which normally carry USB (not only the USB 3.x pins, but also the USB 2 pins in the VirtualLink alternate mode). You could think as USB-PD being below USB, except that it's also not true since you can use USB-C without USB-PD (using only the resistors in the CC pins to detect cable orientation and maximum current).

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