USB-C


Letalis Sonus

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Additionally, the ability to plug it in upside down requires an extra IC directly next to the socket. It simply does not fit into this already totally crammed area and would require an extensive redesign. Just take a look at the "wonky chip".
 

Binky

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Wouldn't full USB-C support (rather than some sort of fallback/legacy mode) require additional hardware support in the SoC, too?

As is always the case with (low-volume) engineering, you're limited by upstream suppliers - and it's hard enough to buy small numbers of high-performance ARM processors at all, let alone ones with latest-and-greatest features.

Realistically, I can't see it being a problem. The miniUSB port on my Pandora still works exactly as I need it to!
 

Letalis Sonus

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Wouldn't full USB-C support (rather than some sort of fallback/legacy mode) require additional hardware support in the SoC, too?
USB-C only defines an "alternate mode" that does not specify what the data lines are being used for, this is being handled by vendor-defined messages on the configuration line. I'm pretty sure that functionality could just as well be part of the aforementioned extra-IC.
 

second exodous

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USB 3 pretty much maxes out the SD card speeds anyway, charging through USB c would be nice though.

Maybe after a few CPU board upgrades well get the Pyra 2 (or Pandora 3) and it will have C. By then C cables will be cheaper anyway.
 

Hellfleck

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I bought a couple of those a while ago : https://voltacharger.com/

they snap on magnetically and do not care about directions ;)

only downside is some of my gear has micro usb sockets which are worn out over time so sometimes the magnetic force from the cable is bigger than the socket friction and I pull the adapter out instead xD
 

Silent-Hunter

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I bought a couple of those a while ago : https://voltacharger.com/

they snap on magnetically and do not care about directions ;)

only downside is some of my gear has micro usb sockets which are worn out over time so sometimes the magnetic force from the cable is bigger than the socket friction and I pull the adapter out instead xD
I want one of those!
 

ible

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If you plug it in the wrong way then it will not fit and you will only have to turn it 90 degrees and try again.

that does beg the question -- why didn't they go all the way in user-friendliness and make it circular? i know power cords are simple enough to do this, but maybe for more complicated wirings that's impossible?

but i suppose down the wire, that's up next for obsoleting hardware in USB-D.
 

Letalis Sonus

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that does beg the question -- why didn't they go all the way in user-friendliness and make it circular?
And fuck all modern smartphone designs by making it way too thick to be useful? What do you think were they thinking about when designing this one?
 

T.T.

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Additionally, the ability to plug it in upside down requires an extra IC directly next to the socket. It simply does not fit into this already totally crammed area and would require an extensive redesign. Just take a look at the "wonky chip".
Being able to plug it in upside down doesn't require an extra IC, USB C simply has duplicates of each pin. One set of signals is on each side of the plug.
 

Letalis Sonus

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USB C simply has duplicates of each pin. One set of signals is on each side of the plug.
USB-C is not symmetrical, it does define an upper and a lower side - all pins are unique and are being dynamically rerouted. It explicitly defines four differential data lines even though the USB connection itself only uses two - this is very important once you add in the alternate mode, which makes all four differential data lines available for whatever purpose you need them - HDMI/MHL, DisplayPort and Thunderbolt are all using the full set of differential data lines in a non-symmetrical fashion. Not to mention that each side has an additional sideband-use pin that is not identical to its mirrored pin on the other side (even though they are currently not used by the USB standard itself).

Even when you're not supporting any kind of alternate mode: Have fun trying to wire up an USB-C jack in a symmetrical fashion on a 2 layer PCB, this is not being covered by the jack itself. You can't wire up both configuration pins to a single line, either, the standard expects the plug to put V_CONN onto the opposite configuration line - doing so would disable all Power Delivery options and lock the port into an USB 2.0 fallback mode.
 
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ible

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Maybe modern smart phones should be a little thicker to accommodate a bigger battery.
 

DAP

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Being able to plug it in upside down doesn't require an extra IC, USB C simply has duplicates of each pin. One set of signals is on each side of the plug.
Unfortunately, it does require an additional IC. It is not just duplicate pins, it is duplicate wires as well. The USB C cable has four pairs of super speed differential pairs along with the USB High Speed differential pair. The USB High Speed differential pair DOES have duplicate pins, so if all you want is USB High Speed, you don't need the additional IC.
The USB Super Speed wires need to be impedance matched point to point connectons, and the system must figure out which two pairs are connected through, and connect only to those pairs that are connected through. This is what the extra IC does, Using some extra pins on the cable, it can figure out which two of the four pairs is connected through, and switch the USB Super Speed connection so that the TX pair and the Rx pair are each connected through in a point to point connection.
At 5 GHz, you would have a bad day if you tried to have multiple connector pins connected to the same signals.
 

second exodous

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I bought a couple of those a while ago : https://voltacharger.com/

they snap on magnetically and do not care about directions ;)

only downside is some of my gear has micro usb sockets which are worn out over time so sometimes the magnetic force from the cable is bigger than the socket friction and I pull the adapter out instead xD
These look nice. The ones I was looking at a while ago were cheap Chinese junk. The main advantage is you only need one cable for every device. My only worry would be the data transfer hit, if they even do data transfer.
 
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