Hi..
 >> What is LSB?
 >  JK> Least Significant Byte
 > Least Significant Bit
 >>  JK>     xchg ah, al
 >>  JK>     in al, 50h     ; MSB of timer 0
 >>  JK>     xchg ah, al
 >>
 >> And MSB?
 >  JK> Most Significant Byte
 > Most Significant Bit
In the context of the question thus placed, the B in MSB does, in fact, stand 
for BYTE. MSB is an abbreviation that has more than one meaning, and one must 
look at the context of it's use to decide which is appropriate.
In the example given, the code is retrieveing the 16-bit value of timer 0, 
which is done by reading the same I/O port twice, once to retrieve the least 
Signivigant BYTE, once to retrieve the most signivigant BYTE. the code then 
"reassembles" the two 8-bit bytes read back into one 16-bit word.
    Craig
--- FMail/386 1.0g
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