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' This example uses the StringAddress routine to pass a Basic string to
' an assembly-language program. The StringLength routine is used to
' determine the length of the string.
 
' Note: To run this program, you must compile the following code and link
' it with the assembled MASM program (shown below in remarks) and the
' appropriate run-time library (VBDCL10.LIB).
 
' To try this example:
' 1. Choose New Project from the File menu
' 2. Copy the code example below to the code window
' 3. Press F5 to run the example
 
 DEFINT A-Z
 
 CLS                                 ' Clear the screen
' Create a variable-length string.
 Message1$ = "This string was sent to MASM for printing."
 CALL PrintMessage1(Message1$)       ' Pass it to MASM to be printed
 
' ; *************************PrintMessage1************************
' ;   This MASM procedure prints a string passed to it by Basic.
'
'             .model      medium, basic       ;Use same model as Basic
' ;Define external (BASIC library) procedures
'             extrn   StringAddress: far
'             extrn   StringLength: far
'
'             .code
' ;Define procedure with one word argument
' PrintMessage1  proc     uses ds,  descriptor
'
'             mov     ax, descriptor          ;Find length of string.
'             push        ax
'             call        StringLength
'             push        ax                  ;Save length on stack.
'
'             mov         ax, descriptor      ;Go find out the
'             push    ax                      ;address of the string
'             CALL    StringAddress           ;data.
'
'             mov         ds, dx              ;Address of string.l.
'             mov         dx, ax
'             mov     bx, 01                  ;Handle of printer
'             pop     cx                      ;Length of string
'             mov     ah, 40h                 ;Have MS-DOS print it
'             int         21h
'             ret
' PrintMessage1   endp
'
'             end