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  Title:    Convert Data                          Flags: O D I T S Z A P C
                                                         ═════════════════
  Syntax:   CBW                                               -none-
            CWD
            CWDE (80386/486 Only)
            CDQ  (80386/486 Only)
 
  See also: MOVSX, MOVZX
 
  Description:
 
     CBW converts a signed byte in AL to a signed word in AX by
     extending the sign bit of AL into all bits of AH.
 
     CWD converts the signed word in AX to a signed word in the DX:AX
     register pair by extending the sign bit of AX into all bits of DX.
 
     CWDE converts a signed word in AX to a signed doubleword in EAX
     by extending the sign bit of AX into all bits of EAX.
 
     CDQ converts the signed doubleword in EAX to a signed quadword in
     the EDX:EAX register pair by extending the sign bit of EAX into
     all bits of EDX.
                                    -♦-