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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)

#131
post #73
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.

Firewire ports can be inserted the wrong way, if the material cheapens out you are in bad luck. Wrong polarity will most likely kill the other device.

I can just imagine what the polarized wall sockets in your house must look like.

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

#133

> It was in 1998 that USB made some real headway, courtesy of the iMac G3, the first computer to ship with only USB ports for external devices (there were no serial or parallel ports). Um, no? The iMac had an Ethernet port, a phone jack for an internal modem, and TWO FIREWIRE PORTS. And Microphone and Speaker jacks.

The Firewire started with the iMac DV in grey.

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

#134
post #90

Earlier quoted context omitted.

It's amazing that it can take you 3 tries to plug in a USB cable which only has 2 correct ways it can be oriented.

The funniest part is that it still takes 3 tries even when you know what you just said.

Hofstadter's Law: It always takes longer than you expect, even when you take into account Hofstadter's Law.

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

#135
post #83

Earlier quoted context omitted.

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…

The worst connector for that problem is those ----ing antenna leads your laptop has for an M2 wifi card.

I broke the ring on a M.2 Wi-Fi card, but installed the cable onto it anyway. I think the part I bent off will probably rip off and get stuck in the cable the next time I take the connector off the card. Here's hoping I'll never have to do that...

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

#136
post #67

Earlier quoted context omitted.

I was responding to the "out for over a decade" part; how long they've been available doesn't mean much if they haven't been very common for consumer electronics for that long. Up until this year I've had only 1 such cable, my phone charger, that could get mixed up in any way... and that one couldn't be mixed up because I didn't have a second unused cable to mix it up with.

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) - there's a convention in that ecosystem that power flows from the A connector to the other end.

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

#137
post #96

Earlier quoted context omitted.

AFAIK there's no such thing as a standards compliant USB-C male to USB-C female extension cable. The very concept goes against the spec[1]. You have a point though; I'm sure there are abominations out there that abuse the USB spec in all sorts of interesting ways, they just haven't been something I've encountered in my years of using USB-C for everything. [1]: https://www.reddit.com/r/UsbCHardware/comments/10xj74r/wh…

Ah, good to know. I'm tempted to respond that this means the spec has failed to address an important use case. But I'm certainly not going to learn enough of the spec to back up that claim.

You're not wrong; it's an unfortunate limitation, even though there are solid technical reasons for it. As a sibling commenter pointed out, a standards-compliant alternative would basically just be a USB hub with a single USB-C port.

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

#138
post #90

Earlier quoted context omitted.

It's amazing that it can take you 3 tries to plug in a USB cable which only has 2 correct ways it can be oriented.

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

This gets you down from 3 tries to 2

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

#139

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…

I think this is a bit hyperbolic. Once you try to implement any standard in practice to billions of people & devices you're going to find the same constraints and similar trade-offs everywhere.

Manufacturers are going to cheap out, always. There's no way around the fact that goods can get on the market claiming a thing that it doesn't do (perfectly) in practice. Tech is littered with semi-compliance. I hate to kick the can down to 'let consumers figure it out' but there's hardly a realistic alternative, you just can't police ~10 billion cables sold a year across ~10 million retailers. I haven't heard of your first example anywhere actually happening, it sounds theoretical more than widespread in practice in 2023, 8 years into this USB-C thing.

As far as cables with different capabilities, what is the alternative here?

1. Physics of signaling demand certain capabilities require higher quality / more expensive cables. Zero chance you get people or manufacturers lined up around the idea of highest common denominator (e.g. 40gbps capable $30 cable when consumer wants a $3 charging cable), and that's sorta moot anyway because...

2. Standards evolve, and we're all tired of playing the game we've played for 50 years in tech of new physical connectors every few years.

It's either a) you have the same physical connector and different cables, or b) different physical connectors that briefly use the same cables before they become differentiated when standards evolve.

The reality is 'it works but not as good' (speed or charge-wise) is a superior tradeoff to 'I have to buy a totally different cable' in the high % of use cases where 'not as good' is possible, which is stuff like 'charge my phone' or 'plug my printer/audio device/whatever in'.

Honestly the only unforced errors I see with USB-C are consumer education related. USB versioning should be simple (3, 4, 5) not intentionally obtuse ("3.2 gen 2x2"), and something like iconography should be added to indicate premium cable capability (specific higher voltage & bandwidth capabilities) to avoid to play the plug in and try it game.

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

#140
> 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 Apple did with lightning.

Then you implement auto crossover detection, (edit: Gah! you don't even have to do that just flip the flipping wires) which had been around for years and is dirt cheap, in the hub. It would have been like, six, more transistors in the hub IC.

edit: I completely forgot that reversible USB 2.0 plugs already exist and use a simpler (and cheaper) method. They just tend not to be so reliable because of the thinner materials and the fact that they're not spec-compliant so they tend to be grey market jobs made for the lowest price possible.

Here is one: https://www.amazon.com/Tripp-Lite-Universal-Reversible-UR050...

No doubling of wires or circuits required, just a thin double-sided PCB.

Was the connector form-factor inherited from an earlier project and the players didn't want to design a new one?

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