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Comment by zellyn | Hacker News Reader

Well, it's not just a simple plug: "The plug itself incorporates a processor which detects the plug's orientation and routes the electrical signals to the correct pins." -- http://en.wikipedia.org/wiki/Lightning_(connector)

Depressingly... "Official Lightning connectors contain an authentication chip that makes it difficult for third-party manufacturers to produce compatible accessories without being approved by Apple."

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All that's true (FULL DISCLOSURE: I work at Apple), but the physical plug that Lightning uses is fantastic. Nothing in there seems to be particularly dependent on the state of technology in 2012.

I mean, USB is better than the physically identical but electrically distinct PS/2 ports, but that's not setting the bar particularly high.

FULL DISCLOSURE: I work at Apple

Unless you got your message vetted through PR, you're in danger of termination now. (Completely not joking. It's happened before.)

USB (a relatively novel rectangular connector) is physically identical to PS/2 (a historically standard round mini DIN connector)? This sort of reasoning is completely alien to me, which is probably why I'll never be as rich as Jobs.

USB connectors don't have any intelligence, they're just a way to connect a few wires together. In that sense, they work exactly like PS/2, AT keyboard connectors, Atari 2600 joysticks, and headphones. The only differences are the shapes and locations of the individual connections.

The lightning connector isn't passive, it contains some active circuitry, so it's not nearly as simple.

Edit: seems I misread the meaning.

A physical connector has an electro-mechanical function, and the PHY layer has an electronic function. Regardless the technology, both are always required.

So, lightning located some (small) part of the PHY in the connector rather than in the client or host (where it would likely be cheaper). Apple could have merely cross-wired the pins on each side of the connector to achieve a reversible design and thus eliminated this excess complexity.

I suspect the design is motivated by IP/counterfeit protection. I do not believe any of that benefits the end user at all.

Right, that was confusing. What I was trying to say is that USB was an improvement on PS2, where the mouse and keyboard ports were identical to the user.

That's how I read that sentence the first time, too, but you can parse that sentence so it's true:

Two USB ports which are electrically identical are superior to two PS/2 ports, one for keyboard and one for mouse, which are electrically different.

IIRC, PS/2 mouse and keyboard ports are electrically identical, and the reason that they can't be used interchangeably is that addressing for PS/2 devices is hardcoded at the software level, i.e. the BIOS always expects a keyboard connected to a specific port and a mouse connected to the other.

If you're willing to sacrifice half of the conductors, you can make it such that, for example, conductor 1 is always on the left.

You could make USB this way easily with 4 conductors on each side whose order is correct regardless of which side of the cable is up. There'd be 8 total conductors on the connector.

I'm actually surprised this isn't the method that Apple decided to go with considering that it is simpler and presumably requires fewer additional parts.

Apple focuses on superficial simplicity. The complexity of the implementation, if hidden, is irrelevant. For example, the Mighty Mouse[1] using capacitive sensors instead of just having two buttons.

[1] https://en.wikipedia.org/wiki/Apple_Mighty_Mouse

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