My Uniwell LX5600F displays the CID. It seems to be stuck and I can not perform any other functions. It will not register a transaction and will not operate in SP, Z or X mode.
How do I rectify the issue?

Terence Gentry, January 2013

I haven't worked with this model. CID usually refers to cash in drawer. Someone may have programmed the CID settings incorrectly. If you want an LX5600 operating or programming manual, one of the users has them listed here

http://the-checkout-tech.com/manuals/cashregisters/uniwell1.php

Registerman, February 2013