Example of Passing Array of Long Integers from Basic to MASM (49386)

SUMMARY

The two programs shown below demonstrate how a Microsoft Basic program passes an array of long (4-byte) integers to assembly language.

This information about interlanguage calling applies to QuickBasic versions 4.00, 4.00b, and 4.50 for MS-DOS, to Microsoft Basic Compiler versions 6.00 and 6.00b for MS-DOS and MS OS/2, and to Microsoft Basic Professional Development System (PDS) versions 7.00 and 7.10 for MS-DOS and MS OS/2.

MORE INFORMATION

For more information about passing other types of parameters between Basic and MASM, search in the Microsoft Knowledge Base using the following word:

BAS2MASM

Code Example

The following Basic program is BLONG.BAS, which creates an array of long integers and passes it to assembly language by far reference:

DEFINT A-Z
   DECLARE SUB MasmSub (BYVAL segment, BYVAL offset, BYVAL number)

   'REM $DYNAMIC     'Can be either STATIC (the default) or DYNAMIC
   DIM l&(1 TO 10)   'Remove comment to define array DYNAMICally

   CLS
   PRINT "Calling assembly routine to fill array elements..."
   CALL MasmSub(VARSEG(l&(1)), VARPTR(l&(1)), 10)
   PRINT "Values in array:"
   FOR i% = 1 TO 10
       PRINT l&(i);
   NEXT
   END

The following program is ALONG.ASM, which receives an array of long integers and fills each array element with a 1:

.MODEL MEDIUM
.CODE
        PUBLIC MasmSub
MasmSub PROC
        push bp
        mov bp,sp
        mov es,[bp+10]   ; get segment of array
        mov bx,[bp+8]    ; get offset of array
        mov cx,[bp+6]    ; get length of array
        mov al,1
next:   mov es:[bx], al  ; put one in the array element
        add bx, 4        ; increment counter to next array element
        loop next        ; loop to assign next array element
        pop bp
        ret 6
MasmSub ENDP
        END

To demonstrate these programs from an .EXE program, compile and link as follows:

BC BLONG.BAS;
MASM ALONG.ASM;
LINK BLONG ALONG;

BLONG.EXE produces the following output:

Calling assembly routine to fill array elements...
Values in array: 1 1 1 1 1 1 1 1 1 1