The terminal can already capture debug messages from an application.  Be sure the customer is using the RETAILMSG macro. An OS with full debug capability is too large to fit into the partition allocated for the device.  If there is a specific driver that they need then we need to build the debug version special.  This is not typical, though.

Their application is in Java.  Will RETAILMSG work in Java too or is it just for C?

I hope someone else knows the answer to that question, I don't

To debug their application?  Or are they trying to get system level debug messages displayed?

Primarily to debug their application.  But system level debug logs could also help them to see what is happening in their application. Thanks