.MODEL SMALL
.CODE
org 100h
proses:
jmp start
oldX dw-1
oldY dw 0

start:
mov ah, 00
mov al, 13h
int 10h
mov ax, 0
int 33h
cmp ax, 0
mov ax, 1
int 33h
check_mouse_button:
mov ax, 3
int 33h
shr cx, 1
cmp bx, 1
jne xor_cursor
mov al, 1010b
jmp draw_pixel
xor_cursor:
cmp oldX, -1
je not_required
push cx
push dx
mov cx, oldX
mov dx, oldY
mov ah, 0dh
int 10h

xor al, 1111b
mov ah, 0ch
int 10h
pop dx
pop cx

not_required:
mov ah, 0dh
int 10h
xor al, 1111b
mov oldX, cx
mov oldY, dx
draw_pixel:
mov ah, 0ch
int 10h

check_esc_key:
mov dl, 255
mov ah, 6
int 21h
cmp al, 27
jne check_mouse_button
stop:
mov ax, 2
int 33h
mov ax, 3
int 10h
mov ah, 1
mov ch, 0
mov cl, 8
int 10h
mov dx, offset msg
mov ah, 9
int 21h
mov ah, 0
int 16h
ret
msg db " press any key.... $"
end proses