Event Aging
The process of aging resets status bit 3 – ConfirmedDTC when a sufficient amount of time has elapsed so that the cause for the error entry is assumedly not relevant anymore. This is often used as a trigger to also clear stored snapshots or extended data from the event memory. But I don't get the healing process. I couldn't find anything about it.
Aged counter Aging Counter The Dem module provides the ability to remove a specific event from the event memory, if its fault conditions are not fulfilled for a certain period of time (operation cycles). This process is called as "aging" or "unlearning". The usage of this feature requires the maintaining of an additional NVRAM block
Healing counter Available both in positive direction, counting up from 0 (healing not started), latching at 255; and in reverse counting down from the healing threshold (healing not started) to 0. The counter is incremented resp. decremented as soon as the healing conditions are fulfilled (at the end of a ‘passed’ tested operation cycle without failed result), irrespective of the status of the ‘ConfirmedDTC ‘ or ‘WarningIndicatorRequested’ status bit. The up-counting data element corresponds to ‘Cycles Tested Since Last Failed’. Both data elements are also calculated for events without indicator.
According to AUTOSAR DEM SWS Document :
Healing of diagnostic events The Dem module provides the ability to activate and deactivate indicators per event stored in the event memory. The process of deactivation is defined as healing of a diagnostic event.
Aging of diagnostic events The Dem module provides the ability to remove a specific event from the event memory, if its fault conditions are not fulfilled for a certain period of time (operation cycles).This process is called as "aging" or "unlearning".
Few points to notice ( According to my point of view ) :
1 - Each one of them has a separate counter and a separate threshold, When the counting value meets the provided threshold, corresponding action is being taken.
2 - Normally, healing comes before aging.
3 - Aging resets the confirmedDTC bit in the status byte of the DTC. Healing just means we have an operation cycle in which the event status byte never had the testFailedThisOperationCycle bit set before.
