Replying to a message of James Vahn to Rejean Lambert:
 JV> page of ports are always on the 8MHz bus, and port 4Fh is
 JV> always unused, so a stable form of jmp $+2.
 
I think it would be highly unwise to rely on this being true forever. Any 
unused port is free for use by any hardware device, unless it is reserved by 
the CPU or system board manufacturer. In the latter case, it would be 
suicidal to use the port to force a delay (remember, this is exactly what 
happened when IBM decided to use the interrupt vectors Intel had reserved for 
CPU use.. take a look at Ralf Brown's interrupt list to see the debacle that 
exists today).
--- FleetStreet 1.20 NR
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