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CALL             Call Procedure                      Flags: not altered

CALL procedure_name

          Logic:    if FAR CALL (inter-segment)
                        PUSH CS
                        CS . dest_seg
                    PUSH IP
                    IP . dest_offset

    CALL transfers control to a procedure that can either be within the
    current segment (a NEAR procedure) or outside it (a FAR procedure).
    The two types of CALLs result in different machine instructions, and
    the RET instruction that exits from the procedure must match the type
    of the CALL instruction (the potential for mismatch exists if the
    procedure and the CALL are assembled separately).

  --------------------------------------------------------------------------
   Operands                  Clocks   Transfers  Bytes   Example
                           byte(word)
   near-proc                 19(23)       1        3     CALL NEAR_PROC
   far-proc                  28(36)       2        5     CALL FAR_PROC
   memptr 16              21(29) + EA     2       2-4    CALL PROC_TABLE[SI]
   regptr 16                 16(24)       1        2     CALL AX
   memptr 32              37(57) + EA     4       2-4    CALL [BX].ROUTINE
  --------------------------------------------------------------------------

       Notes:         For an inter-segment procedure (procedure in a
                      different segment), the processor first pushes the
                      current value of CS onto the stack, then pushes the
                      current value of IP (which is pointing to the
                      instruction following the CALL instruction), then
                      transfers control to the procedure.

                      For an intra-segment procedure (procedure in the
                      same segment), the processor first pushes the
                      current value of IP (which is pointing to the
                      instruction following the CALL instruction) onto the
                      stack, then transfers control to the procedure.

                      CALL can also read the procedure address from a
                      register or memory location.  This form of CALL is
                      called an indirect CALL.