This program provides BASIC programs with access to the program loader (LOAD)
by passing parameters via the system parameter area (SYSPARM).

;BASLOAD.ASM
;----------------------------------------------------------------------------
;
;Inputs:
;  FILE SPEC 1 - A string (len <= 80) with the complete name, including
;  path, of the file to be loaded and executed.
;  Example: 'MAINMENU.EXE' or 'C:\FORMAT.COM'
;  PARAMETER 1  - A string (len <= 80) with the command line parameters
;  to be passed to the program specified in FILE SPEC 1.
;  Example: '' or 'A:'
;  FILE SPEC 2  - Same as 1.
;  PARAMETER 2  - Same as 1.
;
;Outputs:
;  This program gives control to LOAD.
;----------------------------------------------------------------------------




CODE SEGMENT 'CODE'
ASSUME CS:CODE


PUBLIC BASLOAD ;make known to BASIC at link time
BASLOAD PROC FAR

;prologue
PUSH BP ;save BP
MOV BP,SP ;set base for parm list
PUSH DS ;DS -> basic work area
PUSH ES ;ES -> basic work area
MOV DX,'dk' ;interrupt verification switch
INT 77H ;get seg address of sysparm area in AX
MOV ES,AX ;ES -> sysparm area
CLD ;set direction for all moves

;move file spec 1 to sysparm
MOV BX,SS:[BP+12] ;get addr of string descriptor
MOV CX,DS:[BX] ;get length of string into CX
MOV SI,DS:[BX+2] ;get addr of string into SI
MOV DI,0 ;offset into sysparm
REP MOVSB ;move string
MOV BYTE PTR ES:[DI],0 ;make it asciiz string

;move parameter 1 to sysparm
MOV BX,SS:[BP+10] ;get addr of string descriptor
MOV CX,DS:[BX] ;get length of string into CX
MOV SI,DS:[BX+2] ;get addr of string into SI
MOV DI,81 ;offset into sysparm
INC CL ;adjust for cr to be added at end
MOV BYTE PTR ES:[DI],CL ;1st byte is length of string
DEC CL ;re-adjust for move operation
INC DI
REP MOVSB ;move string
MOV BYTE PTR ES:[DI],13 ;add cr to end

;move file spec 2 to sysparm
MOV BX,SS:[BP+8] ;get addr of string descriptor
MOV CX,DS:[BX] ;get length of string into CX
MOV SI,DS:[BX+2] ;get addr of string into SI
MOV DI,163 ;offset into sysparm
REP MOVSB ;move string
MOV BYTE PTR ES:[DI],0 ;make it asciiz string

;move parameter 2 to sysparm
MOV BX,SS:[BP+6] ;get addr of string descriptor
MOV CX,DS:[BX] ;get length of string into CX
MOV SI,DS:[BX+2] ;get addr of string into SI
MOV DI,244 ;offset into sysparm
INC CL ;adjust for cr to be added at end
MOV BYTE PTR ES:[DI],CL ;1st byte is length of string
DEC CL ;re-adjust for move operation
INC DI
REP MOVSB ;move string
MOV BYTE PTR ES:[DI],13 ;add cr to end

;exit to BASIC
POP ES
POP DS
POP BP
RET 8

BASLOAD ENDP

CODE ENDS
END BASLOAD

Designed By Blogger Templates | Templatelib & Distributed By Blogspot Templates