Set your board in "lab" mode (boot flag 0x400) and the RTP will stay
in memory after the problem occurs. Then you can attach the target
shell ('rtp attach' command with the shell in command mode, i.e. with
the "[vxWorks *]#" prompt. If you see the "->" prompt type 'cmd' to
switch the the command mode) to this RTP and use commands like 'ti',
'tt', and 'd' to debug.
The Error Detection & Reporting (ED&R) facility, if configured in,
might also provide you with useful information (dump the log with the
'edrShow' command from the target shell. The ED&R log should hold the
information regarding the exception.
Alternatively if your user-side code is compiled with the -g option
and the RTP is launched from Workbench you should get a dialog when
the RTP fails and I think you should be able to debug from there in
the Workbench environment.
Hope this helps,