> 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 :-)

Post a reply to this message