begin quoting Tom Gal as of Sun, Sep 11, 2005 at 04:28:43PM -0700: > > I can think of three reasons. > > 1) the USB cable end is externally symmetric, usually without any > > orientation markings. > > 2) the USB chassis end (A connector) is externally symmetric > > I'm not really sure how to interpret that because the A connectors > (plug in to your comp or whatever USB Host) always have the USB symbol > facing up.
Not always. Sometimes one way is up, sometimes the other way, and sometimes the receptacles are "on edge". Some connectors aren't even labelled. > As for the other end the full size connectors have rounded > edges and the commonly used mini connectors are even more oddly > shaped. But very small, and hard to tell which way matches the receptacle. > Are you talking about not the cable but the ports themselves? Er, I'm trying to plug a cable into the port, so both. > I'm not saying it doesn't happen to me (impatiently trying to plug > something in while multitasking), but if you use any device enough to > run into the problem, it's likely if you look at the cable it's not a > problem. Except that it obviously *is*. Perhaps you're just the one balancing out the universe ... you guess 90% correctly, which offsets my 90% incorrectly rate, and the universe is happy with an average of 50%.... > > It would have been better to use hermaphroditic connectors, like the > > GR 874 RF connectors. > > I'm not sure what those are, but I'm guessing they didn't care power > on the same bus. Unlike many household appliances most embedded > devices are not built with extra circuitry to handle reversed > polarity. With DC, it's just a matter of a wheatstone bridge, innit? I'm glad to see that more systems are able to auto-crossover ethernet these days. It's so much nicer than having to worry about crossover cables or 'uplink' ports. -Stewart "Let the hardware handle the tedious and error-prone work" Stremler -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
