OP 17 Lights on Buttons

Hello all!

Here's my problem: I finally got my OP17 to work and I have to use 3 colours on my buttons for varius operations (green, red and red flashing).I used function key K4. In General menu I gave it an adress PLC_1 DB1 DBX5.0. In Area Pointers I put down LED assignment Address DB1 DBW4.0, Lenght 1, Aquisition Address 1.0. Ofcourse in PLC program under DB1 on address number 4.0 I put down Type: Word, Initial value W#16#0.

Everything works fine when I put in PLC program address DB1 DBX5.0 for some function(red light is on when function is performing). Same thing happens for address DB1 DBX5.1 only red light is flashing....

My problem is : where is the green light and how do I get it? In OP17 manual it clearly says it's possible. Please advise.