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 Example Passing Numerics from Basic to MASM by Far Reference - Q49385
 
 The two programs below demonstrate how a Basic program can
 pass standard numeric types to assembly language routines.
 
 The following Basic program is BNUMFAR.BAS, which passes standard
 numeric types to assembly language routines:
 
 Code Example
 ------------
 
 DECLARE SUB Numint(SEG i%)
 DECLARE SUB Numlong(SEG lng&)
 DECLARE SUB Numsng(SEG s!)
 DECLARE SUB Numdbl(SEG d#)
 
 i% = 2
 lng& = 4
 s! = 3.4
 d# = 5.6
 
 CLS
 PRINT "         BEFORE","AFTER"
 PRINT "Integer: ";i%,,
 CALL Numint(i%)
 PRINT i%
 
 PRINT "Long   : ";HEX$(lng&),,
 CALL Numlong(lng&)
 PRINT HEX$(lng&)
 
 PRINT "Single : ";s!,
 CALL Numsng(s!)
 PRINT s!
 
 PRINT USING "Double : ##.####            ";d#,
 CALL Numdbl(d#)
 PRINT USING "##.####"; d#
 END
 
 The following program is ANUMFAR.ASM, which accepts standard numerics
 by far reference and alters their values:
 
 .MODEL MEDIUM, BASIC
 .CODE
         PUBLIC Numint, Numlong, Numsng, Numdbl
 Numint  PROC
         push bp
         mov bp, sp        ; Set stack frame.
         push es
         mov es, [bp+8]    ; Get seg.
         mov bx, [bp+6]    ; Get offset.
         mov ax, es:[bx]   ; Get actual integer.
         shl ax, 1         ; Multiply by 2.
         mov es:[bx], ax   ; Put back new value.
         pop es
         pop bp
         ret 4
 Numint  ENDP
 Numlong PROC
         push bp
         mov bp, sp        ; Set stack frame.
         push es
         mov es, [bp+8]    ; Get seg.
         mov bx, [bp+6]    ; Get offset.
         mov cx, es:[bx]   ; Get actual long.
         mov ax, es:[bx+2] ; Switch high and low words.
         mov es:[bx+2], cx ; Put back new value.
         mov es:[bx], ax
         pop es
         pop bp
         ret 4
 Numlong ENDP
 
 Numsng  PROC
         push bp
         mov bp, sp        ; Set stack frame.
         push es
         mov es, [bp+8]    ; Get seg.
         mov bx, [bp+6]    ; Get offset.
         mov ax, es:[bx+2] ; Get actual single.
         or ah, 80h        ; Set sign bit.
         mov es:[bx+2], ax ; Put back new value.
         pop es
         pop bp
         ret 4
 Numsng  ENDP
 
 Numdbl  PROC
         push bp
         mov bp, sp         ; Set stack frame.
         push es
         mov es, [bp+8]     ; Get seg.
         mov bx, [bp+6]     ; Get offset.
         mov ax, es:[bx+6]  ; Get actual double.
         or ah, 80h         ; Set sign bit.
         mov es:[bx+6], ax  ; Put back new value.
         pop es
         pop bp
         ret 4
 Numdbl  ENDP
         END
 
 To demonstrate these programs from an .EXE program, compile and link
 as follows:
 
    BC /O BNUMFAR.BAS;
    MASM ANUMFAR.ASM;
    LINK BNUMFAR ANUMFAR;
 
 BNUMFAR.EXE produces the following output:
 
           BEFORE    AFTER
 Integer:   2         4
 Long   :  4         40000
 Single :   3.4      -3.4
 Double :   5.6000   -5.6000