Bi-Direction pins

All,

In IBIS model, how to model the Bi-direction pins?
The situation is that I have an output buffer that
contains an input buffer as well. There is only
one buffer can be actived at one time. So, I am
not so sure which buffer's model should I put
for the pin.

-- 
Best Regards,
			Vincent Chang
			
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*  Vincent Chang                         TI MSG ID: hui8              *
*  Design Automation                     mailto:vchang@memh.ti.com    *
*  Memory Products Design                http://www.memh.ti.com/~mcad *
*  Texas Instruments Inc. MS 657         Phone: (281) 274-3167        *
*  PO Box 1443, Houston, TX 77251        Fax:   (281) 274-2067        *
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