stack segment
db 128 dup (0)
stack ends
assume cs:code
code segment
start:
mov ax,stack
mov ss,ax
mov sp,128
push cs
pop ds
mov ax,0
mov es,ax
mov si,offset int9
mov di,204h
mov cx,offset int9end-offset int9
cld
rep movsb
push es:[9*4]
pop es:[200h]
push es:[9*4+2]
pop es:[202h]
cli
mov word ptr es:[9*4],204h
mov word ptr es:[9*4+2],0
sti
mov ax,4c00h
int 21h
int9:
push ax
push bx
push cx
push es
in al,60h
pushf
call dword ptr cs:[200h]
cmp al,9Eh ;1
jne int9ret
mov ax,0b800h
mov es,ax
mov bx,0 ;2
mov cx,2000
s:
mov byte ptr es:[bx],'A' ;3
add bx,2
loop s
int9ret:
pop es
pop cx
pop bx
pop ax
iret
int9end:
nop
code ends
end start |
