SNIP_CLASSIC_DEM_SECTION_7_7_2_4_Event_displacement

7.7.2.4 Event displacement Event displacement means, that the most insignificant, already existing event memory entry is replaced by a new event memory entry, which needs to be stored. During displacement, the most insignificant entry gets lost. [SWS_Dem_00400] Upstream requirements: RS_Diag_04118 ⌈If the event retention want to allocate a new event memory entry and there is no free event memory entry available, the Dem module shall check according [SWS_Dem_00406] for allocated event memory entries to be displaced by the new event memory entry.⌋ Note: If the event memory size is configured to cover all possible events, no displacement will occur. [SWS_Dem_00401] Upstream requirements: RS_Diag_04118 ⌈The Dem module provides the configuration parameter DemEventDisplacementStrategy (refer to DemPrimaryMemory or DemUserDefinedMemory) defining whether the existing event memory entry can be displaced or not.⌋ [SWS_Dem_00402] Upstream requirements: RS_Diag_04118 ⌈If event displacement is disabled (DemEventDisplacementStrategy in DemPrimaryMemory or DemUserDefinedMemory selects DEM_DISPLACEMENT_NONE), the Dem module shall not displace existing event memory entries if the event memory is full.⌋ [SWS_Dem_00406] Upstream requirements: RS_Diag_04118 ⌈If event displacement is enabled (DemEventDisplacementStrategy selects DEM_DISPLACEMENT_FULL in DemPrimaryMemory or DemUserDefinedMemory or DEM_DISPLACEMENT_PRIO_OCC), the Dem module shall perform the following sequence by combination of the different displacement criteria: 1. Priority (refer [SWS_Dem_00403]) 2. Active/Passive status (configurable, only for DEM_DISPLACEMENT_FULL in DemPrimaryMemory or DemUserDefinedMemory) (refer [SWS_Dem_00404]) 3. Occurrence (refer [SWS_Dem_00405]) ⌋ Note: Priority needs to have Fuel system/Misfire over the rest (US/EU5) and Class A before B1,B2, C (Euro VI). [SWS_Dem_00403] Upstream requirements: RS_Diag_04118 ⌈If displacement strategy is DEM_DISPLACEMENT_FULL or DEM_DISPLACEMENT_PRIO_OCC (refer to DemPrimaryMemory or DemUserDefinedMemory), the Dem module shall displace lower prioritized events by higher prioritized events.⌋ [SWS_Dem_00404] Upstream requirements: RS_Diag_04118 ⌈If displacement strategy is DEM_DISPLACEMENT_FULL(refer to DemPrimaryMemory or DemUserDefinedMemory), the Dem module shall displace passive events preferably.⌋ For details see chapter 7.7.1.4. [SWS_Dem_00405] Upstream requirements: RS_Diag_04118 ⌈If displacement strategy is DEM_DISPLACEMENT_FULL or DEM_DISPLACEMENT_PRIO_OCC (refer to DemPrimaryMemory or DemUserDefinedMemory), the Dem module shall displace older stored events in the chronological order prior to newer stored events (refer [SWS_Dem_00412] and [SWS_Dem_00787]).⌋ [SWS_Dem_00407] Upstream requirements: RS_Diag_04118 ⌈If no event memory entry for displacement was identified, the Dem module shall discard the storage request.⌋ [SWS_Dem_00692] Upstream requirements: RS_Diag_04118, RS_Diag_04071 ⌈If an event is reported and an event memory entry with the same priority exists and the existing event is not tested in this operation cycle (TestNotCompletedThisOperationCycle bit == 1), the Dem shall displace the existing event with the reported event.⌋ [SWS_Dem_00693] Upstream requirements: RS_Diag_04178 ⌈During displacement, if an event is reported and an event memory entry with the same priority exists and the existing event is tested in this operation cycle (TestNotCompletedThisOperationCycle bit == 0), the Dem shall not displace the existing event with the reported event.⌋ [SWS_Dem_00695] Upstream requirements: RS_Diag_04195 ⌈If the configuration parameter DemOBDEventDisplacement is set to TRUE all emission related events with the following conditions shall not be considered during the displacement mechanism and shall not be displaced from error memory: Eventold is emission related AND (Eventold triggers MIL indicator OR (Eventold holds legislative Freeze Frame AND has equal or higher priority) OR Pending-DTC of Eventold==1)⌋ [SWS_Dem_00696] Upstream requirements: RS_Diag_04195 ⌈If the configuration parameter DemOBDEventDisplacement is set to FALSE, no special rules of displacement are applied to emission related events. In this case emission related events shall be displaced like every other event.⌋ [SWS_Dem_00408] Upstream requirements: RS_Diag_04118 ⌈If the event memory entry for displacement was identified, the Dem module shall remove this event memory entry from the event memory.⌋ Note: This removed event memory entry should now used for the pending storage trigger. [SWS_Dem_00409] Configurable reset of the confirmedDTC bit in case of displacement Upstream requirements: RS_Diag_04067, RS_Diag_04118 ⌈If an event memory entry was removed during displacement and the configuration parameter DemResetConfirmedBitOnOverflow is set to TRUE, the Dem module shall reset the UDS DTC status bit 3 to 0.⌋ [SWS_Dem_01395] Configurable reset of the pendingDTC bit in case of displacement Upstream requirements: RS_Diag_04067, RS_Diag_04118 ⌈If an event memory entry was removed during displacement and the configuration parameter DemResetPendingBitOnOverflow is set to TRUE, the Dem module shall reset the UDS DTC status bit 2 to 0.⌋ [SWS_Dem_01186] Upstream requirements: RS_Diag_04067, RS_Diag_04118 ⌈If an event memory entry was removed during displacement, the UDS status bit 5 shall be reset to 0 in case of DemStatusBitHandlingTestFailedSinceLastClear is set to DEM_STATUS_BIT_AGING_AND_DISPLACEMENT and DemResetConfirmedBitOnOverflow is set to true.⌋