Screens frozen during flight

[CaptainOver]

Doing a long flight last night, switching in and out of external views to admire the scenery and I eventually noticed that the GTNXi had stopped updating (both devices on the 310) and I had far overshot my turn.  I could hear sounds when I clicked the knob/menu button, but the touchscreens didn't respond - and even stayed lit when I toggled the avionics master in desperation.  Sounds like it maybe lost its connection to the back-end?
Are there any logs/debug info I can grab or view if this happens again?