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

pcgamer.com

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

#411

Post by musicale »

userbinator wrote: post #194
snakeyjake wrote: post #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…

There are also reversible USB plugs that are a single "tongue", inheriting that design from USB drives that don't have any plug to speak of but look more like a card-edge connector: https://www.pcgamer.com/youre-telling-me-we-could-have-had-r... https://2b.com.eg/en/2b-cv177-cable-usb-type-a-reversible-pl...

PCgamer:

> Incidentally, the late Steve Jobs deserves a tip-of-the-hat for helping USB become a long-lasting standard. 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). That came three years after USB 1.0 debuted, with a data rate of 12Mbps.

Also PCgamer:

> Given that it was a protocol designed to counter the typically Apple expense of sticking Firewire onto a motherboard, cost was the biggest reason for the eventual success of USB as a thing

Apple started building FireWire 400 into Macs when 12Mbps USB 1.0 was not really an equivalent. USB 2.0 didn't make the cut for the first generation iPod but was supported on subsequent models.

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

#412

Post by jdblair »

dylan604 wrote: post #215
jdblair wrote: post #197

I used to "bedazzle" my USB cables. Bedazzling is when you decorate something with little plastic reflective jewel stickers. I always put the jewel in the same side (the "top") so I could feel which way the cable should be oriented. Then I could be confident I had the orientation correct without looking. I called this USBedazzling. The other folks in the office didn't think it was a funny as I did.

what if the port was in the opposite orientation, or worse, vertically oriented?

I knew my own gear and how the ports were oriented.

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

#413

Post by rusk »

musicale wrote: post #411
userbinator wrote: post #194

Earlier quoted context omitted.

There are also reversible USB plugs that are a single "tongue", inheriting that design from USB drives that don't have any plug to speak of but look more like a card-edge connector: https://www.pcgamer.com/youre-telling-me-we-could-have-had-r... https://2b.com.eg/en/2b-cv177-cable-usb-type-a-reversible-pl...

PCgamer: > Incidentally, the late Steve Jobs deserves a tip-of-the-hat for helping USB become a long-lasting standard. 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). That came three years after USB 1.0 debuted, with a data rate of 12Mbps. Also PCgamer: > Given that it was a protocol…

> the first computer to ship with only USB ports

I remember presenting this in a project as an undergraduate and I was challenged by the lecturer that it would be highly unusual for a consumer device to ship without RS232 and I could only say “yeah”

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

#414

Post by rasz »

JoblessWonder wrote: post #247
dylan604 wrote: post #207

Earlier quoted context omitted.

>edit: Gah! you don't even have to do that just flip the flipping wires) Isn't that essentially what all ethernet cables do? it's not like this something never done before.

When was Auto MDI-X introduced? A quick google failed to get me an answer but I remember USB being available while I still needed a crossover cable to hook up 2 switches.

Together with 1Gbit ratification, so ~2000

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

#415

Post by Moru »

rzzzt wrote: post #200
stevage wrote: post #193

Earlier quoted context omitted.

Even having a bump on the rubber moulding as part of the standard would have solved the problem.

The USB symbol goes on top, IIRC. Edit: ninja'd by an enormous amount of people elsewhere in the thread, gah.

Vertically aligned motherboards are hard to judge what "up" is. Usually up is where the expansion boards are plugged in. But not all computer users know how a computer looks inside.

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

#416

Post by IshKebab »

nucleardog wrote: post #332
IshKebab wrote: post #223

Earlier quoted context omitted.

I used a Bluetooth analyser once that had a USB-C connector that only plugged in one way. It had a dedicated "wrong way around" LED to tell you to rotate it. Kind of hilarious. It's the only example I've ever seen though so not a real problem IMO. The cables issue is real, but I don't really see the alternative. Would everyone really be happier if all USB-C cables had to be expensive thick 40 Gb/s 100W cables? No.

Could they not have done… something else besides make everything visually identical? At least give us a fighting chance? In a perfect world require every port to have the supported modes displayed beside it, and every cable to have the supported modes etched on the metal connector or something? Lightning bolt for PD, little screen icon for video, something? It will fall apart as soon as cheap unlicensed electronics h…

They do try to get manufacturers to print symbols next to the ports, but that isn't really a full solution anyway. There are too many modes, and you have things like hubs to deal with.

I suspect the real answer is better software support to tell you why something isn't working.

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

#417

Post by gsich »

yborg wrote: post #131
gsich wrote: post #73

Earlier quoted context omitted.

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.

There are none. (besides 400V sockets)

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

#418

Post by oleg_antonyan »

> one of the greatest inventions of all time

Seriosly? Overcomplicated protocol to make it very hard to bit-bang and thus pay USB-IF for every chip, every logo. There was already 100mbit Ethernet at that time, just add power wires and use existing network stack in software, but how can you squish money from it?! Ofc they needed something new proprietary, overcomplicated, with terrible reliability. USB is the curse of modern hardware.

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

#419

Post by microtonal »

userbinator wrote: post #274
kybernetikos wrote: post #250

Earlier quoted context omitted.

Couldn't original USB have used TRRS? That's better than reversible - an infinite number of orientations are allowed.

That shorts together a lot of the contacts as you're plugging it in. There are of course various devices which somehow ended up using TRRS for USB, but unplugging/plugging those while powered is definitely not recommended: https://www.reddit.com/r/ErgoMechKeyboards/comments/rt083u/a... http://www.totekinternational.com/35mm-trrs-to-usb-a-male-ca... https://pinoutguide.com/PortableDevices/ipod_shuffle_pinout....

Most of this is just cheap design on part of the ergomech community. It's not that hard to add some protection. E.g. some keyboards use a Schottky diode on VCC for reverse polarity protection and ESD protection diodes to protect the data lines:

https://github.com/zsa/docs/blob/master/Ergodox%20V5-L.pdf

Of course the design requirements of USB would be different, since you'd always plug/yank the cable on a machine that is on, rather than protect against doing this accidentally sometime. Given that, it probably made more sense to completely avoid the issue.

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

#420

Post by kybernetikos »

userbinator wrote: post #274
kybernetikos wrote: post #250

Earlier quoted context omitted.

Couldn't original USB have used TRRS? That's better than reversible - an infinite number of orientations are allowed.

That shorts together a lot of the contacts as you're plugging it in. There are of course various devices which somehow ended up using TRRS for USB, but unplugging/plugging those while powered is definitely not recommended: https://www.reddit.com/r/ErgoMechKeyboards/comments/rt083u/a... http://www.totekinternational.com/35mm-trrs-to-usb-a-male-ca... https://pinoutguide.com/PortableDevices/ipod_shuffle_pinout....

I'm not an expert but couldn't you just make the tip live and not connect the rest until that's connected? Or have a switch for when the plug is fully inserted. I see that it's a problem for sure, but it seems easier than the problems they solved to make usb c reversible
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