Of course no one can help you with this because simply it is hardware dependent.
Are these lights memory mapped? If yes to which address? If no, to which port?
The basic idea behind toggling something on and off is to XOR the bit (or the port) it is connected to with 1 because x XOR 1 = !x
So, first start with initial state by masking off the bit (AND it with zero)
Then decide how you are going to perform the delay time between On and Off
Then write something like this
Mask Off
Loop
XOR with 1
Call Delay
XOR with 1
EndLoop
Walid Magd
Engwam@Hotmail.com