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>> OK, so if I'm understanding this right... The 74126 (go look it up)
>> contains 4 "buffers" - gates who's output is logically equal to their
>> input. But each gate also has an "enable" pin. When the enable pin is
>> high, the gate works like normal. When the enable pin goes low, it's
>> like the output pin isn't connected to anything any more.
>
> Yes exactly.
>
>> And it seems that this allows you to connect several outputs together,
>> forming a kind of wired-OR configuration, provided that at all times
>> only one gate is "enabled".
>
> Yep, you could make a simple address decoder logic circuit (ie have a 2
> bit binary input to select which of the 4 buffers to enable) - that way
> you would guarantee only 1 would be active at a time. If you were to
> connect a 2-bit counter to the 2-bit address lines you would then have a
> 4-bit parallel to serial converter :-)
I was thinking more about routing bundles of signals from place to
place. The "obvious" thing to do is use logic gates to combine the
signals, but I guess using these weird 3-state systems allows you to
save a few logic gates (and hence ICs, wiring, and ripple time).
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