Working on a project at work.
A control interface to bridge between our system and a motion controller's architecture.
Motion controller uses an RS-232 based ascii interface that's text based.
With our serial interface it will send commands to the board, where the controller will mount and take input.
Our interface should have direct communication with the device, I don't believe any additional serial device is require since ours uses ASCII text based commands as well.
Some info
controller
http://www.copleycontrols.com/motion/pdf/SEM-ds.pdfhttp://www.copleycontrols.com/motion/pdf/Binary-Serial.pdf