>         mov old_lite,al         ; Set flag.
 > ;        mov ax,1000h            ; Turn video on.
 > ;        mov bx,0F12h
 > ;        int 10h
 > ;        jmp exit
 SL>  I understand the code before. But why you commented out
 SL> these instructions.  I really want to make of use of int in
 SL> the handler. i guess you got problem  too :-)
Yes, a problem; I run an old Hercules monochrome. ;-)  The commented 
code is for VGA/EGA. Uncomment the commented, and comment the uncomented 
block of code following it. There are four blocks of video code total, 
look a bit more carefully at it and it should become clear. My appologies 
for the confusion.
Another way to use interrupts is to hook int 28h;  when DOS isn't tooo 
busy, it calls int 28. Basically you'll have an int28 ISR setting a flag
within the code/data space of your main ISR.
--- timEd 1.01
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