myapp_ex04b.c

This network protcol stack,it is very strong and powerful!

  /* Allocate a message for the MLME (We should check for NULL). */
  pMsg = MSG_AllocType(mlmeMessage_t);
  if(pMsg != NULL)
  {
    /* This is a MLME-START.req command */
    pMsg->msgType = gMlmeScanReq_c;
    /* Create the Start request message data. */
    pScanReq = &pMsg->msgData.scanReq;
    /* gScanModeED_c, gScanModeActive_c, gScanModePassive_c, or gScanModeOrphan_c */
    pScanReq->scanType = scanType;
    /* ChannelsToScan & 0xFF - LSB, always 0x00 */
    pScanReq->scanChannels[0] = (uint8_t)((SCAN_CHANNELS)     & 0xFF);
    /* ChannelsToScan>>8 & 0xFF  */
    pScanReq->scanChannels[1] = (uint8_t)((SCAN_CHANNELS>>8)  & 0xFF);
    /* ChannelsToScan>>16 & 0xFF  */
    pScanReq->scanChannels[2] = (uint8_t)((SCAN_CHANNELS>>16) & 0xFF);
    /* ChannelsToScan>>24 & 0xFF - MSB */
    pScanReq->scanChannels[3] = (uint8_t)((SCAN_CHANNELS>>24) & 0xFF);
    /* Duration per channel 0-14 (dc). T[sec] = (16*960*((2^dc)+1))/1000000.
       A scan duration of 5 on 16 channels approximately takes 8 secs. */
    pScanReq->scanDuration = 5;
    
    /* Send the Scan request to the MLME. */
    if(MSG_Send(NWK_MLME, pMsg) == gSuccess_c)
    {
      Uart_Print("Done\n");
      return errorNoError;
    }
    else
    {
      Uart_Print("Invalid parameter!\n");
      return errorInvalidParameter;
    }
  }
  else
  {
    /* Allocation of a message buffer failed. */
    Uart_Print("Message allocation failed!\n");
    return errorAllocFailed;
  }
}

/******************************************************************************
* The App_HandleScanActiveConfirm(nwkMessage_t *pMsg) function will handle the
* Active Scan confirm message received from the MLME when the Active scan has
* completed. The message contains a list of PAN descriptors. Based on link
* quality inforamtion in the pan descriptors the nearest coordinator is chosen.
* The corresponding pan descriptor is stored in the global variable coordInfo. 
*
* The function may return either of the following values:
*   errorNoError:       A suitable pan descriptor was found.
*   errorNoScanResults: No scan results were present in the confirm message.
*
******************************************************************************/
uint8_t App_HandleScanActiveConfirm(nwkMessage_t *pMsg)
{
  uint8_t panDescListSize   = pMsg->msgData.scanCnf.resultListSize;
  panDescriptor_t *pPanDesc = pMsg->msgData.scanCnf.resList.pPanDescriptorList;
  uint8_t rc = errorNoScanResults;
 
  /* Check if the scan resulted in any coordinator responses. */
  if(panDescListSize != 0)
  {
    /* Initialize link quality to very poor. */
    uint8_t i, bestLinkQuality = 0;
    
    /* Check all PAN descriptors. */
    for(i=0; i<panDescListSize; i++, pPanDesc++)
    {
      /* Only attempt to associate if the coordinator
         accepts associations and is non-beacon. */
      if( ( pPanDesc->superFrameSpec[1] & gSuperFrameSpecMsbAssocPermit_c) && 
          ((pPanDesc->superFrameSpec[0] & gSuperFrameSpecLsbBO_c) == 0x0F) )
      {
        /* Find the nearest coordinator using the link quality measure. */
        if(pPanDesc->linkQuality > bestLinkQuality)
        {
          /* Save the information of the coordinator candidate. If we
             find a better candiate, the information will be replaced. */
          memcpy(&coordInfo, pPanDesc, sizeof(panDescriptor_t));
          bestLinkQuality = pPanDesc->linkQuality;
          rc = errorNoError;
        }
      }
    }
  }
  /* ALWAYS free the PAN descriptor list */
  MSG_Free(pMsg->msgData.scanCnf.resList.pPanDescriptorList);
  
  return rc;
}


/******************************************************************************
* The App_SendAssociateRequest(void) will create an Associate Request message
* and send it to the coordinator it wishes to associate to. The function uses
* information gained about the coordinator during the scan procedure.
*
* The function may return either of the following values:
*   errorNoError:          The Associate Request message was sent successfully.
*   errorInvalidParameter: The MLME service access point rejected the
*                          message due to an invalid parameter.
*   errorAllocFailed:      A message buffer could not be allocated.
*
******************************************************************************/
uint8_t App_SendAssociateRequest(void)
{
  mlmeMessage_t *pMsg;
  mlmeAssociateReq_t *pAssocReq;

  Uart_Print("Sending the MLME-Associate Request message to the MAC...");
  
  /* Allocate a message for the MLME message. */
  pMsg = MSG_AllocType(mlmeMessage_t);
  if(pMsg != NULL)
  {
    /* This is a MLME-ASSOCIATE.req command. */
    pMsg->msgType = gMlmeAssociateReq_c;
    
    /* Create the Associate request message data. */
    pAssocReq = &pMsg->msgData.associateReq;
 
    /* Use the coordinator info we got from the Active Scan. */
    memcpy(pAssocReq->coordAddress, coordInfo.coordAddress, 8);
    memcpy(pAssocReq->coordPanId,   coordInfo.coordPanId, 2);
    pAssocReq->coordAddrMode      = coordInfo.coordAddrMode;
    pAssocReq->logicalChannel     = coordInfo.logicalChannel;
    pAssocReq->securityEnable     = FALSE;
    /* We want the coordinator to assign a short address to us. */
    pAssocReq->capabilityInfo     = gCapInfoAllocAddr_c;
      
    /* Send the Associate Request to the MLME. */
    if(MSG_Send(NWK_MLME, pMsg) == gSuccess_c)
    {
      Uart_Print("Done\n");
      return errorNoError;
    }
    else
    {
      /* One or more parameters in the message were invalid. */
      Uart_Print("Invalid parameter!\n");
      return errorInvalidParameter;
    }
  }
  else
  {
    /* Allocation of a message buffer failed. */
    Uart_Print("Message allocation failed!\n");
    return errorAllocFailed;
  }
}

/******************************************************************************
* The App_HandleAssociateConfirm(nwkMessage_t *pMsg) function will handle the
* Associate confirm message received from the MLME when the Association
* procedure has completed. The message contains the short address that the
* coordinator has assigned to us. This address is 0xfffe if we did not specify
* the gCapInfoAllocAddr_c flag in the capability info field of the Associate
* request. The address and address mode are saved in global variables. They
* will be used in the next demo application when sending data.
*
******************************************************************************/
void App_HandleAssociateConfirm(nwkMessage_t *pMsg)
{
  /* This is our own extended address (MAC address). It cannot be modified. */
  extern const uint8_t aExtendedAddress[8];
  
  /* If the coordinator assigns a short address of 0xfffe then,
     that means we must use our own extended address in all
     communications with the coordinator. Otherwise, we use
     the short address assigned to us. */
  if( (pMsg->msgData.associateCnf.assocShortAddress[0] >= 0xFE) && 
      (pMsg->msgData.associateCnf.assocShortAddress[1] == 0xFF) )
  {
    myAddrMode = gAddrModeLong_c;
    memcpy(myAddress, (void *)aExtendedAddress, 8);
  }
  else
  {
    myAddrMode = gAddrModeShort_c;
    memcpy(myAddress, pMsg->msgData.associateCnf.assocShortAddress, 2);
  }
}


/******************************************************************************
* The App_WaitMsg(nwkMessage_t *pMsg, uint8_t msgType) function does not, as
* the name implies, wait for a message, thus blocking the execution of the
* state machine. Instead the function analyzes the supplied message to 
* determine whether or not the message is of the expected type.
* The function may return either of the following values:
*   errorNoError: The message was of the expected type.
*   errorNoMessage: The message pointer is NULL.
*   errorWrongConfirm: The message is not of the expected type.
*
******************************************************************************/
uint8_t App_WaitMsg(nwkMessage_t *pMsg, uint8_t msgType)
{
  /* Do we have a message? If not, the exit with error code */
  if(pMsg == NULL)
    return errorNoMessage;

  /* Is it the expected message type? If not then exit with error code */
  if(pMsg->msgType != msgType)
    return errorWrongConfirm;

  /* Found the expected message. Return with success code */
  return errorNoError;
}


/******************************************************************************
* The following functions are called by the MAC to put messages into the
* Application's queue. They need to be defined even if they are not used
* in order to avoid linker errors.
******************************************************************************/

uint8_t MLME_NWK_SapHandler(nwkMessage_t * pMsg)
{
  /* Put the incoming MLME message in the applications input queue. */
  MSG_Queue(&mMlmeNwkInputQueue, pMsg);
  return gSuccess_c;
}

uint8_t MCPS_NWK_SapHandler(mcpsToNwkMessage_t *pMsg)
{
  /* If the message is not handled anywhere it must be freed. */
  MSG_Free(pMsg);
  return gSuccess_c;
}

uint8_t ASP_APP_SapHandler(aspToAppMsg_t *pMsg)
{
  /* If the message is not handled anywhere it must be freed. */
  MSG_Free(pMsg);
  return gSuccess_c;
}