Simple CTU

I've got a SLC 500 with no program in it other than a rung with I:1/0 (XIC) going to a counter (C5:0).

Input I:1/0 is wired and working (online it goes green with button pushed), but the counter will not count up.

C5:0, CTU, Preset 100, ACC 0.

Even tried a OSR with the C5:0

What can I possibly be doing wrong with such a simple circuit?

Thanks!

Never mind, it works if I keep that logic on ladder 2 and not ladder 3, I must be missing something about ladders...

If you wish to place logic in a program other than program 2 you must place a JSR to that program in a scanned program. (Program 2 is the only program which is automatically scanned.)