Important Notice

The pages on this site contain documentation for very old MS-DOS software, purely for historical purposes. If you're looking for up-to-date documentation, particularly for programming, you should not rely on the information found here, as it will be woefully out of date.

 ◄Map►                                       ◄Up► ◄Contents► ◄Index► ◄Back►
────────────────────────────────────────────────────────────────────────────
 
;* LoadPtr - Macro to load far address into segment:register pair, or
;* near address into register.
;*
;* Params:  sgmnt - Segment to be loaded with segment address
;*          reg - Register to be loaded with offset address
;*          pointer - Pointer to address
;*
;* Shows:   Instructions - lds     les
;*          Directives - MACRO     IF        IFIDNI     ELSE
;*                       ELSE      IFENDIF   .ERR       ENDM
;*          Operators - < >       ;;
 
LoadPtr MACRO sgmnt, reg, pointer       ;; Macro definition
    IF @DataSize                        ;; If far pointer, and
        IFIDNI <sgmnt>, <ds>            ;;   if 1st argument is DS,
            lds reg, pointer            ;;   load DS:reg with far address
        ELSEIFIDNI <sgmnt>, <es>        ;;   or if 1st argument is ES,
            les reg, pointer            ;;   load ES:reg with far address
        ELSE                            ;; Generate error if not DS or ES
            .ERR <First argument must be DS or ES>
        ENDIF
    ELSE                                ;; If near pointer,
        IFIDNI <sgmnt>, <es>            ;;   and if segment is ES,
            push ds                     ;;   ensure ES points to
            pop  es                     ;;   same segment as DS
        ENDIF
        mov reg, pointer                ;; Then load reg with near address
    ENDIF
ENDM
                                    -♦-