Bob1984

Thanks for the replies, that looks very interesting I will give it a try tomorow

I have 14 bits, each is set when a particular fault occurs, the problem is once 1 fault occurs and the machine stops it then causes more "red herring" faults. I need to detect which fault happened first and report this as the reason the machine stopped. I can do it the long way:- A M100.0 AN M100.1 AN M100.2 etc... but this would result in 14 very similar networks, and what if my fault list grows to say 100? Is there a quicker/more efficient way of detecting which bit was set first?