J1939ParseSHM

Valid for: CANoe DE • CANoe4SW DE

Function Syntax

long J1939ParseSHM(pg* pgSHM, dword & sdmPgn, byte& sdmSourceAddress, byte& sdmDestinationAddress, byte& sequenceNumber, dword & crc):

Description

Provides data of the SDM message, which are contained in payload of the SHM message according to SAE J1939-76.

Parameters

pgSHM: SHM to parse. DLC of SHM shall be 8.
sdmPgn: Returns the PGN of the SDM.
sdmSourceAddress: Returns the source address of the SDM.
sdmDestinationAddress: Returns the destination address of the SDM.
sequenceNumber: Returns the sequence number of the Safety Data Group (SDG).
crc: Returns the SDM Data CRC.

Return Values

0: SHM is successfully parsed.
-1: DLC of a PG is not 8 bytes.

Example

on pg SHM
{
  long result;
  dword sdmPgn, crc;
  byte sdmSourceAddress, sdmDestinationAddress, sequenceNumber;

  result = J1939ParseSHM(this, sdmPgn, sdmSourceAddress, sdmDestinationAddress, sequenceNumber, crc);
  if (result < 0)
  {
    write("J1939ILParseSHM failed with error %i", result);
  }
  else
  {
    if ((sdmPgn == pgnOfConsumedMsg)
        && (sdmDestinationAddress == saOfConsumedMsg)
        && (sdmSourceAddress == daOfConsumedMsg))
    {
      // validate sequence number of SHM and store store CRC to validate it when SDM is received
    }
  }
}

J1939CalculateCrcOfSDM • J1939ParseSHM