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Comment by computerbob | Hacker News Reader

What I have never figured out is why they don't color coordinate which side is up or down. Green is up, red is down. It would give a instant visual idea of which way to plug it in. Can't image it would cause the cost to go up.

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Red and green? http://en.wikipedia.org/wiki/Color_blindness

As a deuteranomalous trichromat (aka, what is popularly called "red-green colorblind"), yes, red and green are fine.

I've explained this in more detail before:

http://www.reddit.com/r/askscience/comments/1oomt1/how_are_r...

If I understand correctly, based on what you said and comparing it to the rainbows on wikipedia, a trichromat would be fine with red vs green, since they are distinguishable, but nearby colors to those (red -> orange, green -> blue) look more similar (different shades of the same color). And looking into it some more, a dichromat would be fine as well because the two colors would be distinguishable because green would be essentially dark and red would be light (i.e. "the dark side goes up" in the USB example).

> Green is up, red is down.

You do realize USB ports can be vertical, and usually are on (USB-enabled) wall outlets, displays and desktop computers right?

And that's the simple case of vertical (flipped 90 on the long axis compared to most laptops) with USB-enabled extension cords lying on the floor, you plug straight down.

So rotate in one direction for vertical for consistency, and color-code the plug for everything that could benefit from it. Matching red/green is far easier than "which side has that mostly-invisible black piece of plastic".

> So rotate in one direction for vertical for consistency

There is no consistency, your USB port may be on the left, right or back of your screen, what's the useful thing to standardize then? And it can jut out from a wall. And on a desktop tower, the USB port can be on the front or the back, and the user may install the machine so it is accessed from the left, the right or either.

Left/right/back of screen is still the same direction. If it's counter-clockwise from green-up, it's green-left everywhere, including walls. On anything parallel with the floor you're right - so color-code the plug.

Quite a few years ago when USB was new, a trip to the local hobby store with about $3 cash resulted in a green model builders "paint pen" which is pretty much what it sounds like, a felt tip pen that releases paint. The paint dries out inside the pen after a couple years. I would imagine depending on your local graffiti problem these might be banned even more severely than spray cans, although in a civilized area they should be available?

Anyway the next discovery is I charge my phone face down to protect the glass, so I have to plug in upside down. Rightside up and Upside down connectors are commercially available for PCBs because the manufacturers have no idea which side might be up in a finished product. So you've converted the problem from figuring out which side of a cable is up, to memorizing which devices you own that have to be flipped upside down. Of course a dot of the same color paint fixes that although it might look ugly on a phone if done sloppily enough.

A greater annoyance is should the USB charger input be on the top, bottom, right or left side of all phones? I think I've seen it all.

Google managed to colour-coöordinate their Glass charger, so that the wall plug is black-white the same way the cable is, but didn't have a good answer for how to do the device side of the plug.

See https://phandroid.s3.amazonaws.com/wp-content/uploads/2013/0...

In addition to the other issues with this, a standard orientation would require either the PCB the connector's mounted on to be orientated a certain way (potentially having a knockon effect for other design decisions in the device) or require a whole load of different PCB mounted USB connectors. Both would add cost which the manufacturers would much rather do without. In the cheapest devices, the orientation of the USB port would probably be the first thing to go out the window, making the whole exercise redundant.

What's needed is a robust connector with an easily visually determined orientation and the sort of power transmission capabilities that the new USB PD standard has.

Left and right puts a spanner in the works.

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