XCHG             Exchange Registers                  Flags: not altered
 
XCHG destination,source
 
          Logic:    destination <--> source
 
    XCHG switches the contents of its operands, which may be either bytes
    or words.
 
  --------------------------------------------------------------------------
   Operands                  Clocks   Transfers  Bytes   Example
                           byte(word)
   accumulator, reg16          3          -        1     XCHG AX,SI
   memory, register       17(25) + EA     2       2-4    LOCK XCHG SEMPHOR, DX
   register, register          4          -        2     XCHG CL,DL
  --------------------------------------------------------------------------
 
       Notes:         Used in conjunction with the LOCK prefix, this
                      instruction is particularly useful when implementing
                      semaphores to control shared resources.

Seealso:


 MOV 
 PUSH 
 POP 
 XLAT 
 EA