SNIP_CLASSIC_DEM_SECTION_7_11_2_4_Access_event_related_data

7.11.2.4 Access event related data This section defines the APIs, to get access to the event related data (refer to chapter 7.7.7.1 and chapter 7.7.7.3) stored with the DTCs in the event memory of the Dem via diagnostics. Furthermore, access to WWH-OBD relevant PIDs stored in a freeze frame is made available. Details concerning freeze frame handling can be found in ISO-14229-1[2] and ISO 27145-3[22]. Example for the mapping of a PID to a DID: PID $04 –> DID 0xF404 Note: The data returned include the DTCSnapshotRecordNumberOfIdentifiers (Num of DIDs) as defined by ISO-14229-1[2] for the response message to service 0x19 0x05. [SWS_Dem_01268] ⌈If the API Dem_SelectFreezeFrameData is called, the Dem shall use the DTC selected by Dem_SelectDTC and the RecordNumber as a target for the following API calls: • Dem_GetNextFreezeFrameData • Dem_GetSizeOfFreezeFrameSelection ⌋ [SWS_Dem_01269] ⌈The API Dem_SelectFreezeFrameData triggers the Dem internal Freeze Frame selection process on the event memory assigned to the ClientId. The Dem shall provide the result of the selection process in the return value of the API calls following the Dem_SelectFreezeFrameData call, see [SWS_Dem_01268].⌋ [SWS_Dem_01270] Upstream requirements: SRS_BSW_00369 ⌈If any of the APIs requiring a Dem_SelectFreezeFrameData (see [SWS_Dem_01268]) are called without a prior call to Dem_SelectFreezeFrameData, the Dem shall report the Det error DET_E_WRONG_CONDITION.⌋ [SWS_Dem_01271] Upstream requirements: SRS_BSW_00369 ⌈If any of the APIs requiring a Dem_SelectFreezeFrameData is called without a prior call to Dem_SelectFreezeFrameData, the Dem shall report the Det error DEM_E_WRONG_CONDITION.⌋ [SWS_Dem_00071] ⌈The function Dem_GetNextFreezeFrameData shall copy the specific data identifiers (DIDs) of the freezeframe record selected by the API Dem_SelectFreezeFrameData for the specified ClientId to the destination buffer provided by the DestBuffer parameter. The Dem shall transmit these data as a complete record with the Buffer format.⌋ For Buffer format see figure 7.48. [SWS_Dem_00576] ⌈If the RecordNumber selected by the API Dem_SelectFreezeFrameData is set to 0x00, Dem_GetNextFreezeFrameData shall provide the event/DTC specific OBD equivalent freeze frame record.⌋ Note: Retrieving record 0x00 with Dem_SelectFreezeFrameData and Dem_GetNextFreezeFrameData is only supported if the Dem module supports OBD (refer to DemOBDSupport) Data #N Data #1 1st DID Nth DID ... Byte 2..3 Byte 4..j Byte j..k Byte k..(k+2) Byte (k+2)..n requested freeze frame record Data element #N Data element #1 ... RecordNum Num of DIDs Byte 0 Byte 1 calculated (e.g. 1), or configured (e.g. first value from list) Figure 7.48: Buffer format used by Dem_GetNextFreezeFrameData Note: The data returned include the DTCSnapshotRecordNumber (RecordNum) and DTCSnapshotRecordNumberOfIdentifiers (Num of DIDs) as defined by ISO-14229- 1[2] for the response message to service 0x19 0x04. In contradiction to the Dcm PIDstructure handling, the DIDstructure is handled within the Dem module. Therefore, the Dem returns already full freeze frame records according to the response layout. This results in an optimized Dem/Dcm interface. [SWS_Dem_00630] ⌈If a single DTC is selected and the API Dem_SelectFreezeFrameData is called with a valid RecordNumber which is not stored, Dem_GetNextFreezeFrameData shall return E_OK and BufSize 0 (empty buffer).⌋ [SWS_Dem_00074] Upstream requirements: RS_Diag_04205 ⌈The function Dem_GetSizeOfFreezeFrameSelection shall return the size of the requested freeze frame record(s) by Dem_SelectFreezeFrameData for the specified ClientId, which represents the number of user data bytes, including any freeze frame headerinformation (according to the format defined in [SWS_Dem_00071]).⌋ Note: If the record number value 0xFF is requested, the Dem considers the size of all stored freeze frame records according to [SWS_Dem_00074]. [SWS_Dem_01389] Requested size for not configured snapshot records Upstream requirements: RS_Diag_04205 ⌈If Dem_GetSizeOfFreezeFrameSelection is called and the selected freeze frame record number is not configured, the Dem shall return DEM_NO_SUCH_ELEMENT.⌋ [SWS_Dem_01348] Select freeze frame data for single DTCs only Upstream requirements: RS_Diag_04244 ⌈In case the function Dem_SelectFreezeFrameData is called and the DTC selected by Dem_SelectDTC is not a single DTC but a group of DTC, the Dem shall return DEM_WRONG_DTC.⌋ [SWS_Dem_01349] Select extended data record for single DTCs only Upstream requirements: RS_Diag_04245 ⌈In case the function Dem_SelectExtendedDataRecord is called and the DTC selected by Dem_SelectDTC is not a single DTC but a group of DTC, the Dem shall return DEM_WRONG_DTC.⌋ [SWS_Dem_01272] ⌈If the API Dem_SelectExtendedDataRecord is called, the Dem shall use the DTC selected by Dem_SelectDTC and the ExtendedDataNumber as a target for the following API calls: • Dem_GetNextExtendedDataRecord • Dem_GetSizeOfExtendedDataRecordSelection ⌋ [SWS_Dem_01273] ⌈The API Dem_SelectExtendedDataRecord triggers the Dem internal extended data record selection process on the event memory assigned to the ClientId. The Dem shall provide the result of the selection process in the return value of the API calls following the Dem_SelectExtendedDataRecord, see [SWS_Dem_01272].⌋ [SWS_Dem_01274] Upstream requirements: SRS_BSW_00369 ⌈If any of the APIs requiring a Dem_SelectExtendedDataRecord (see [SWS_Dem_01272]) are called without a prior call to Dem_SelectExtendedDataRecord, the Dem shall report the Det error DEM_E_WRONG_CONDITION.⌋ [SWS_Dem_00075] ⌈The API Dem_GetNextExtendedDataRecord shall copy the complete data of the requested extended data record by Dem_SelectExtendedDataRecord API for the specified ClientId to the destination buffer (DestBuffer). The function shall transmit these data as a complete record with the Buffer format. The extended data record number is placed as the first byte in the copied data.⌋ For Buffer format see figure 7.49. Data element #n Data element #1 … Extended Data Record Buffer ExtendedData RecordNumber Byte n Byte 0 Byte 1 Figure 7.49: Buffer format used by Dem_GetNextExtendedDataRecord