Described is a mechanism for receiving new data at an auxiliary device
associated with a main computer system, and processing that new data
within the auxiliary device firmware to take some action. The receipt and
processing of the data is independent of whether the main computer system
is in a powered-up state (online) or powered-down state (offline). A
cache that maintains the user application data for offline navigation may
be updated with new data, either to change existing data in the cache or
add a new navigation path. The received data can be processed to perform
other actions, depending on the context of that data as determined by
auxiliary processing.