Their is one that will show you how many boxes you have programmed, but it has been a couple of years since I had to buy some more RTU's and can't remember the commands. If I have more time today, I'll look around some more.

Mike Jones
"A people that values its privileges above its principles soon loses both."
- Dwight D. Eisenhower (1890-1969), Inaugural Address, January 20, 1953