SAP Acquisition and Sampling

The way to set a basic SAP receive application is as follows:

• A receive channel must be obtained using the mxfModuleChannelGet() or mxfModuleChannelAllGet() functions using MXF_SCLASS_RX_CHANNEL subclass.
• If this is a sampling application, the sampling buffer must be allocated using the mxfRxSamplingBufferAlloc() function or allocated internally using the mxfRxSamplingBufferGet() function.
• If this is a queuing application then use the mxfRxAcqBufferGet() to get the buffer handle allocated.
• A RX Virtual Link must be created using mxfA664VlCreate() with the VL parameters stored in a MXF_A664_VL_PARAM structure.
• A RX COM port must be created using mxfA664PortCreate() with the port parameters stored in a MXF_A664_PORT_PARAM structure. The portParam.portType must be set to MXF_A664_PORT_TYPE_SAP. The portParam.mode must be set to MXF_A664_PORT_MODE_QUEUING for acquisition or MXF_A664_PORT_MODE_SAMPLING for sampling.
• For a sampling application, the sampling kill time can be set with the mxfRxSamplingKilltimeSet() function to allow the invalidation of the last reception if the data is too old. Starting and reading the sampled data can be performed with mxfRxSamplingStart() and mxfA664RxSamplingRead().
• For a queuing application, the acquisition must be started using the mxfRxAcqStart() function. The mxfA664RxAcqRead() function is then used to read the messages from the buffer and place them in the record structure.

The MXF_A664_DATAREC structure must be used for reading an ARINC 664 message with queuing type.

Example

ar664_aperiodicSap.c
The snippet below demonstrates the basic steps needed to setup a SAP Receive application.

#define DATARECS_BUFFER_SIZE_MAX      64*1024

#define DST_IP_ADRS                "10.0.0.222"
#define DST_UDP_PORT                     5678

HMXF_SERVER server = 0;
HMXF_PORT portRx = 0;
HMXF_VL vlRx = 0;
HMXF_BUFFER rxBuffer = 0;
HMXF_MODULE  module = 0;
HMXF_DEVICE  device = 0;
HMXF_CHANNEL phyChn = 0;
MXF_A664_DATAREC*  rxRec = NULL;
MXF_A664_VL_PARAM vlParam;
MXF_A664_PORT_PARAM portParam;
uint32 dstIpAdrs = 0;
uint64 usedBytes, freeBytes;
uint64 msgCount = 0;
uint32 recordIdx, dataIdx;
uint32 vlid = 100;
uint32 rc;
uint64 count = 0;
MXF_A664_DATAREC* recPtr;
uint64 recordIdx, dataIdx;
uint64 status, msgsCount, bytesCount;
uint32 dataSize;
char srcAddress[32];
uint32 address;

   // Initialize server, allocate base resources
   rc = mxfSystemInit(server);

   // Get the first device handle
   if (!rc)
      rc = mxfSystemDeviceGet(server, 0, &device);

   // Get the first A664 module
   if (!rc)
      rc = mxfDeviceModuleAllGet(device, MXF_MODULE_A664, 1, &count, &module);

   // Obtain the first ARINC 664 Phy channel (Phy logical #0)
   if (!rc && count)
      rc = mxfModuleChannelAllGet(module, MXF_CLASS_A664, MXF_SCLASS_RX_CHANNEL, 1, &count, &phyChn);

   // If module or channel not found, return an error
   if (!rc && !count)
      rc = MAXT_ERROR_NOT_FOUND;

   // Set Timebase
   if (!rc)
      rc = mxfSystemTimeBaseSet(server, MXF_TIMEBASE_DEVICE_NSEC);      

   ...

   // Create the reception (RX) virtual link
   if (!rc)
   {
      memset(&vlParam, 0, sizeof(MXF_A664_VL_PARAM));
      vlParam.VLId = vlid;
      vlParam.frameType = MXF_A664_FRAME_TYPE_ARINC664;
      vlParam.direction = MXF_A664_VL_DIR_RX;
      vlParam.frameSizeMax = 512;
      vlParam.dir.Rx.Mac.skewMax = 4 * 1000 * 1000;
      vlParam.dir.Rx.Mac.rmPSNRange = 2;

      rc = mxfA664VlCreate(phyChn, &vlParam, &vlRx);
   }

   // Create SAP RX port
   if (!rc)
   {
      inet_pton(AF_INET, SRC_IP_ADRS, &dstIpAdrs);

      memset(&portParam, 0, sizeof(MXF_A664_PORT_PARAM));
      portParam.portType = MXF_A664_PORT_TYPE_SAP;
      portParam.family = MXF_A664_PORT_FAMILY_IPV4;
      portParam.mode = MXF_A664_PORT_MODE_QUEUING;
      portParam.dir.Rx.network = MXF_A664_NETSELECT_ALL;
      portParam.dir.Rx.maxBuffers = 16;
      portParam.dir.Rx.bufferSize = 1518;
      portParam.type.SAP.destAddress.port = DST_UDP_PORT;
      portParam.type.SAP.destAddress.version.IPv4.address = nothl(dstIpAdrs);

      rc = mxfA664PortCreate(vlRx, &portParam, &portRx);
   }

   // Get buffer handle automatically allocated for the port
   if (!rc)
      rc = mxfRxAcqBufferGet(portRx, &rxBuffer);

   if (!rc)
   {
      rxRec = malloc(DATARECS_BUFFER_SIZE_MAX);
      memset(rxRec, 0, DATARECS_BUFFER_SIZE_MAX);
      if (!rxRec)
         rc = MAXT_ERROR_MEM;
   }

   // Set acquisition mode
   if (!rc)
      rc = mxfRxAcqModeSet(rxBuffer, MXF_RXACQ_MODE_LINEAR);

   // Start acquisition, check status
   if (!rc)
      rc = mxfRxAcqStart(rxBuffer, MXF_RXACQ_FLAG_DEFAULT, 0, 0);

   if (!rc)
   {
      rc = mxfRxAcqBufferStatusGet(rxBuffer, &status, &msgCount, &usedBytes, &freeBytes);
      if (!rc && (status & MXF_RXACQ_STATUS_RUNNING))
         printf("Acquisition Running\n\n");
   }

   ...

   // Read records 
   rc = mxfA664RxAcqRead(rxBuffer, 0, DATARECS_BUFFER_SIZE_MAX, &status, &msgsCount, &bytesCount, rxRec);
   if (!rc)
      printf("%llu records received\n\n", msgsCount);

   recPtr = rxRec;
   for (recordIdx = 0; recordIdx < msgsCount && !rc; recordIdx++)
   {
      printf("  %03llu: timeTag=%012llu, Size=%u", recordIdx, recPtr->timeTag, recPtr->dataSize);

      address = htonl(recPtr->type.Sap.ipAddress);
      inet_ntop(AF_INET, &address, srcAddress, sizeof(srcAddress));
      printf("        SAP Source Address: %s:%u\n", srcAddress, recPtr->type.Sap.udpPort);

      printf("\n        data=");

      dataSize = recPtr->dataSize;

      for (dataIdx = 0; dataIdx < dataSize; dataIdx++)
      {
         printf("%02X ", recPtr->data[dataIdx]);

         if (!((dataIdx + 1) % 8) && (dataIdx + 1 < recPtr->dataSize))
            printf("\n             ");
      }

      printf("\n\n");

      mxfA664NextDataRecordPtrGet(recPtr, &recPtr);
   }

   ...

   // Terminate Acquisition
   if (!rc)
      rc = mxfRxAcqStop(rxBuffer);

   if (!rc)
      rc = mxfRxAcqClear(rxBuffer);

   if (!rc)
     rc = mxfRxAcqBufferFree(rxBuffer);

  // Free COM ports
  if (!rc)
     rc = mxfA664PortRelease(portRx);

  // Free VL(s)
  if (!rc)
     rc = mxfA664VlRelease(vlRx);

  // Free datarec buffers
  if (rxRec)
     free(rxRec);

  mxfSystemTerminate(server);
  mxfServerDisconnect(server);

  ...