Num Lock , Caps Lock or Scroll Lock

Unknown

I just want to make a phun app, so, I am wondering , How may I turn off the Num Lock , Caps Lock and (or) Scroll Lock in assembly ? I'm useing tasm to compile . (if that should make any difference ).

Thanks. Ivar.

Unknown

: I just want to make a phun app, so, I am wondering , How may I turn off the Num Lock , Caps Lock and (or) Scroll Lock in assembly ? I'm useing tasm to compile . (if that should make any difference ).

: Thanks. Ivar.

at 0040h:0017h is the byte that holds the status of this (and other) keys.

with 0 the list significant bit, and 7 the most significant bit,

bit 4 set : scroll-lock is on

bit 5 set : num-lock is active

bit 6 set : caps-lock is active

check the following examples:

turn on scroll-lock:

mov bx,40h

mov ds,bx

or byte ptr [17h],10h ; (00010000 binary)

turn off num lock:

mov bx,40h

mov ds,bx

and byte ptr [17h],0DFh ; (11011111 binary)

if caps-lock is on, turn it off, if it is off, turn it on:

mov bx,40h

mov ds,bx

xor byte ptr [17h],40h ; (01000000 binary)

hope I helped

/Andreas