The current code will scan frequencies, select a cell and camps on it.
No SIM is inserted. Paging requests and Immediate assginments can be seen.
When inserting a SIM card (uncomment it in app_mobile.c), location update
is triggered after selecting a cell. The RACH request is sent, an
Immediate assignment is received, the dedicated mode is requested.
Nothing happens then, because no confirm / abort of layer 2 is received.