I have 5 cnc machines, and I simply want to know how many hours every day that each machine has run. I want to trend this info, and I also want to view it live.
I am trying to find the slickest way to do this inexpensively. I can easily get an open/closed signal (or 0V/5V) out of the machine, how can I get this info into a PC? I would like to stay away from parallel port, as we don't have many PC's with them anymore.
Is their a breakout board for USB or ethernet that could do this?
I have looked into dataloggers, but most seem overkill (or too expensive) for what I am trying to do.

Thanks!
Joe