Code:
lookup2 led_chk, [%0000000000,%0000000001, %0000000011, %0000000111, %0000001111, %0000011111, _
%0000111111, %0001111111, %0011111111, %0111111111, %1111111111], LED
could be :

Code:
LED = $FF : LED = LED >> (9 - led_chk)