Currently for a BB interface you cannot tell easily if it has been modified since last reading and when the data was recorded. Up to now this does not pose a problem since we had one strict main loop and everything was executed linear but in two situations you really need that data:

• A long running concurrent task breaks the linearity and thus there are likely cycles where no new data is available
• If data is accessed with a remote BB connection (for example from within RCSoftX) the timing constraints do not hold any longer and no association between the in-Fawkes runtime and the external process runtime can be made.

To avoid working on old data (or working at all because if no data has changed you are likely to get the same results anyway) a flag is necessary if new data is available and a time stamp helps weighting the data properly (for example if there are additional data sources with fresher data).

This should be implemented at base interface level to provide global flags. I can't see a specific need for per-data-field flags and time stamps as we had in RCSoftX.