I would like some help why the monitor flickers when the parallel port cable is plugged in with the control box powered up? It stops when you pull out the cable. Also it sometimes trips the E-stop, with or without machine operation.

I suspect you have a grounding issue. Ensure that grounding on the machine is done as it should. Noise travels on the cables and could cause limit switch to trigger unexpected!

There are many threads on this issue! See below thread for one!

http://www.machsupport.com/forum/index.php/topic,22676.0.html

I'm sure it will help! Good luck!

CD