JV>Since a write is needed, it must be an unused port, and it appears 4Fh
JV>is a good candidate.
A better location is 0EDh.  In fact, it is used within the BIOS code of the 
company that I work for between back-to-back OUT/IN instructions to ensure 
that the hardware has had a chance to process the OUT prior to the IN 
instruction.
Location 0EDh is a read-only location so writing to it has no effect.
 * KingQWK 1.05 # [PK] * May Your Next Leap, Be The Leap Home.
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