anelok: Y-Box draft update
edorfaus at xepher.net
Fri Jan 17 22:47:00 EST 2014
On 01/17/2014 11:32 AM, Werner Almesberger wrote:
> Nick found the grandmother of all stupid mistakes: the USB A connector
> was flipped, neatly connecting VBUS to GND and D+ to D-.
Oh yikes. That could have gotten bad in a hurry had you started
connecting things to it.
Indeed, thanks, Nick!
I did something similar not too long ago (except with wires instead of
traces), with an RTC chip and an FPGA that I was playing around with
connecting together. I was careless and connected the RTC's V+ to system
GND and vice versa, and was wondering why it wasn't responding on its
data interface, until I noticed the plastic smell (and figured out what
it was). That RTC chip was *hot*.
I got really lucky though - after it cooled down, it still worked, it
had just gotten reset/blanked out. (That annoyed me a little, since I
had been trying to read out the factory data in its NVRAM, just to see
if there was anything interesting in there - but I was of course glad
the chip wasn't broken worse.)
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