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USB inventor explains why the connector was not designed to be reversible (2019)

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Re: USB inventor explains why the connector was not designed to be reversible (2019)

#151
post #6

It didn't really need to go in either way. It just needed to not be rotationally symmetrical while only going in one way. Firewire only went in one way but it was never an issue because it's shape conveyed a clear orientation.

The fact that the inventor doesn't see this obvious fact honestly boggles the mind.

Re: USB inventor explains why the connector was not designed to be reversible (2019)

#152
post #83

I know everybody is still on the high from USB-C but I'm still going to go on the record it will be one of the biggest disasters in cable history. 1) There's going to be video-only cables; low-voltage only cables; etc and this time everything is usb-c so you can literally only tell which ables work by testing all of the dozen cables instead of the 1-2 USB-As you have. 2) The connector is symmetrical but the pins aren…

3) The most fragile part (the wafer in the center of the receptacle) is on the expensive-to-repair device, while the least fragile part is on the cheap-to-replace cable. HDMI makes this same mistake. With USB-A, at least the plastic part on the device is relatively robust, and with Lightning, both plug and socket were rather robust (albeit prone to debris incursion). With older pin-type connectors like VGA and DVI, t…

Im not sure this is true, the part in the cable is just tiny pins and far more vulnerable than the wafer. For years now I've dug woodchips and other junk out of my phones usb-c socket with paperclips and never came close to damage. It seems sufficiently recessed to prevent all but the most aggressive attack.

Edit: in fact, trying now it seems to be perfectly recessed that I can't even push on it from an angle with the connector, it has to go straight in a bit before it even touches, on any of my devices

Re: USB inventor explains why the connector was not designed to be reversible (2019)

#153
Fun fact: the Nokia 2780 Flip, despite using USB-C, only accepts the cable in one orientation. Put a cable in upside down, and nothing happens. Confirmed with the charger it comes with and one C–C cable that I already possessed.

(Additional fun fact: the box says it uses Micro-USB.)

Re: USB inventor explains why the connector was not designed to be reversible (2019)

#154
post #2

They didn't have to double the wiring, just add wiring to the other side of the connector. That is barely 2 cm of wiring, at most. Also, manufacturers could have made the connectors in a way that would clearly show which side is the top and which is the bottom. So none of the issues had to happen but lazy manufacturers and gullible inventors caused all of this on their own.

I bought a JBL headset which USB power cable is reversible, instead of a big plastic piece for half the plug, it has a thin strip of plastic, so the block of plastic of the port side can go in either side of the plug: https://images.nexusapp.co/assets/4a/75/a0/5733575.jpg But I guess it might just have two wires (+5V and ground) and no data wires (I can't check it now because I'm at work).

I had a USB cable with a reversible A plug, but after a few months/years it would stop charging (because the pins either wouldn't make contact with the A socket, or the wires snapped off the pins).

Re: USB inventor explains why the connector was not designed to be reversible (2019)

#155

I know everybody is still on the high from USB-C but I'm still going to go on the record it will be one of the biggest disasters in cable history. 1) There's going to be video-only cables; low-voltage only cables; etc and this time everything is usb-c so you can literally only tell which ables work by testing all of the dozen cables instead of the 1-2 USB-As you have. 2) The connector is symmetrical but the pins aren…

This could have been as well been a prediction 8 years ago, because in the mean time all of this happened.

regarding 1) look at this post from 2019: https://people.kernel.org/bleung/now-how-many-usb-c-to-usb-c... I imagine it only got worse in the mean time.

regarding 2) I have seen various posts in the past of devices that only work if the cables are connected in a specific orientation. Technical background is discussed here: https://acroname.com/blog/why-usb-c-connections-sometimes-do...

Re: USB inventor explains why the connector was not designed to be reversible (2019)

#156
post #38
post #30

Earlier quoted context omitted.

> There's going to be video-only cables From my understanding I think that is not technically possible because to pass video they need the data lines but maybe I'm mistaken? IIUC again even if it did work I think these would be non-compliant. People hell-bent on doing non-compliant things would do it irrespective of any design. > low-voltage only cables That's a given due to physical constraints (length, diameter: wo…

> From my understanding I think that is not technically possible because to pass video they need the data lines but maybe I'm mistaken? Counterexample: The Meta Quest link cables use a USB-C style connector but internally are very different from a regular cable.

They are regular (fiber optic) USB-C cables.

Re: USB inventor explains why the connector was not designed to be reversible (2019)

#157

> Making USB reversible to begin with would have necessitated twice as many wires and twice as many circuits, and would have doubled the cost. This is... not correct. You can make USB reversible with 1 extra pin and 1 extra wire. Grounds on pins 1 and 5, data on pins 2 and 4, and VCC on pin 3. Then have those pins on both sides of the plug and a socket with a single set of contacts on one side. That's BASICALLY what…

> Then you implement auto crossover detection, dwhich had been around for years

Mdi-x/auto crossover for ethernet was introduced in 1999, that is after USB (1996) was designed, not sure of the technique was known at that time

Re: USB inventor explains why the connector was not designed to be reversible (2019)

#158

Earlier quoted context omitted.

I've found a trick but have trouble explaining it to people - especially if they haven't build a computer before. The plastic bit inside of the plug usually goes on the side facing whatever board it's interfacing with. For example, looking straight on from the back of an ATX case, it's usually on the left side - where the motherboard mounts Front panel connectors are anarchy... but at least they're usually visible

Another trick is that the USB standard says the USB logo should be facing up, so you should always try it first with the logo facing up. Not every device follows that standard and not every device has a clear top/bottom, but this really cuts down on the proportion of failed attempts.

No way! I didn't know that was part of the standard! Very useful "trick" indeed, unless of course, the USB port is placed vertically...

Re: USB inventor explains why the connector was not designed to be reversible (2019)

#159

This page was difficult to read on my mobile due to ads. Here is a link to the source of the interview mentioned in the headline: https://text.npr.org/2019/06/21/734451600/ever-plugged-a-usb...

Install an ad blocker, friend! Firefox + uBlock Origin on Android, or 1Blocker on iOS.

You can also use Orion on iOS, it has built in ad-blocking or you can install Ublock Origin extension.

Re: USB inventor explains why the connector was not designed to be reversible (2019)

#160
post #136

Earlier quoted context omitted.

I've been using USB-C on basically every consumer electronics device I've used over nearly the past decade. Over the years I have accumulated: 1. A laptop with a USB-C power/data/DisplayPort port 2. A phone with a USB-C power/data port 3. Multiple USB power banks which use a single USB-C port for both charging and discharging 4. A smartwatch with a dock that uses USB-C 5. Multiple flashlights with USB-C charging 6. M…

I'm an Android user, and for your points 5, 6, 7, and 8 all of mine are USB-A to Micro USB (except for a flashlight bought this year which came with a USB-A to USB-C cable, and I use wraparound bluetooth headphones instead of earbuds and get the feeling those designs are just extremely rarely updated). No displayport or smartwatch here, and my power banks all came with A-to-micro or A-to-C cables (mostly the former)…

Yes, I have seen some products still using micro-B. I've generally just avoided them because I don't want to have to carry another type of cable, so maybe that's colored my perception a bit of how widespread USB-C usage is.

For the products you've purchased that came with an A-to-C cable, have you tried using them with a plain C-to-C cable? In my experience usually that will "just work". (Maybe there are some power banks out there that don't support outputting power through their USB-C port. If those exist I've managed to avoid them so far.)

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