>> 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
Wrong.  There is NO "Least Significant Bit" or "Most Significant Bit".
Those words only have significance when talking about the two bytes in a 
word, or the "LSW" and "MSW" (Most Significant Word and Least Significant 
Word) when talking about double words.
Bits are numbered, since there's usually 8 of them in a byte.
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