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| assume cs:code
stack segment
db 128 dup(0)
stack ends
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, 3bh
jne int9ret
mov ax, 0b800h
mov es, ax
mov bx, 1
mov cx, 2000
s:
inc byte ptr es:[bx]
add bx, 2
loop s
int9ret:
pop es
pop cx
pop bx
pop ax
iret
int9end:
nop
code ends
end start
|
