Re: gEDA-user: Fun challenge: cat-5 cable tester

[DJ Delorie <dj@xxxxxxxxxxx>]

> and I'm probably missing something blatantly obvious to everybody
> else,

It's not blatantly obvious, but I included R1-8 just to protect the
GPIO ports from shorts.  If the cable is shorted, you don't want to
have a Voh GPIO and a Vol GPIO tied together.

The resistors on the far end of the cable are significantly larger, so
that the effects of the protection resistors are minimal.

Example: R1-8 are 220 ohms each.  R9-16 are more like 10k ohms.


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