Handheld Remote control for awning,rear jacks.slides,etc.?

To the OP, if you think Cardinal has one installed and you don't have the remote you'll first need to verify if this true. You'll need to find the control box for the remote which is located behind a panel or cabinet near most of the systems wiring.

Most trailers that have the remote system are built by Lippert (LCI) so that's one thing to look for. If you can't find the control box then I'll bet your trailer doesn't have it.