On 6/14/07, jamesp@intertex.net <jamesp@intertex.net> wrote:

>  If the external AND gate has one GPIO connected to each input, and
>  assuming it's a 6 input AND gate, ALL pins would have to be HIGH for
>  the output to go HIGH. If there are any unused inputs on the AND gate,
>  ie an 8 input AND gate, pull each of them HIGH with a 10K or so ohm
>  resistor.

That makes sense.

However, each GPIO goes to one AND-input (and one red LED) each, and
from the same input it goes through the cable in question to test, and
the opposite end of the cable goes to the second AND-input. The
AND-output goes to a green LED.

This means as soon as one GPIO goes high, one AND-input and one red
LED goes high, and if the cable is functional, the other end makes the
second AND-input high, making the output high, making the green LED
lit.

I'm not sure if I'm making sense, but I hope so.


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