it()。進入到ZDApp_Init中：

void ZDApp_Init( byte task_id )
{
  uint8 capabilities;

  // Save the task ID
  ZDAppTaskID = task_id;

  // Initialize the ZDO global device short address storage
  ZDAppNwkAddr.addrMode = Addr16Bit;
  ZDAppNwkAddr.addr.shortAddr = INVALID_NODE_ADDR; //0xFFFE
  (void)NLME_GetExtAddr();  // Load the saveExtAddr pointer.

  // Check for manual"Hold Auto Start"
  //

ZDApp_Init首先檢測SW1是否被按下，如果SW1被按下，裝置將處於DEV_HOLD狀態，不會進入組網狀態，這裡我們要特別注意。如果SW1沒有被按下，那麼程式將呼叫ZDOInitDevice來開啟裝置。

uint8 ZDOInitDevice( uint16 startDelay )

{

  uint8 networkStateNV = ZDO_INITDEV_NEW_NETWORK_STATE;

  uint16 extendedDelay = 0;

  if ( devState == DEV_HOLD )

  {

    // Initialize the RAM items table, in case an NV item has been updated.

    zgInitItems( FALSE );

  }

  ZDConfig_InitDescriptors();

  //devtag.071807.todo - fix this temporary solution

  _NIB.CapabilityFlags = ZDO_Config_Node_Descriptor.CapabilityFlags;

#if defined ( NV_RESTORE )

  // Get Keypad directly to see if a reset nv is needed.

  // Hold down the SW_BYPASS_NV key (defined in OnBoard.h)

  // while booting to skip past NV Restore.

  if ( HalKeyRead() == SW_BYPASS_NV )

    networkStateNV = ZDO_INITDEV_NEW_NETWORK_STATE;

  else

  {

    // Determine if NV should be restored

    networkStateNV = ZDApp_ReadNetworkRestoreState();

  }

  if ( networkStateNV == ZDO_INITDEV_RESTORED_NETWORK_STATE )

  {

    networkStateNV = ZDApp_RestoreNetworkState();

  }

  else

  {

    // Wipe out the network state in NV

    NLME_InitNV();

    NLME_SetDefaultNV();

    // clear NWK key values

    ZDSecMgrClearNVKeyValues();

  }

#endif

  if ( networkStateNV == ZDO_INITDEV_NEW_NETWORK_STATE )

  {

    ZDAppDetermineDeviceType();

    // Only delay if joining network - not restoring network state

    extendedDelay = (uint16)((NWK_START_DELAY + startDelay)

              + (osal_rand() & EXTENDED_JOINING_RANDOM_MASK));

  }

  // Initialize the security for type of device

  ZDApp_SecInit( networkStateNV );

  if( ZDO_INIT_HOLD_NWK_START != startDelay )

  {

    devState = DEV_INIT;    // Remove the Hold state

    // Initialize leave control logic

    ZDApp_LeaveCtrlInit();

    // Check leave control reset settings

    ZDApp_LeaveCtrlStartup( &devState, &startDelay );

    // Leave may make the hold state come back

    if ( devState == DEV_HOLD )

    {

      // Set the NV startup option to force a "new" join.

      zgWriteStartupOptions( ZG_STARTUP_SET, ZCD_STARTOPT_DEFAULT_NETWORK_STATE );

      // Notify the applications

      osal_set_event( ZDAppTaskID, ZDO_STATE_CHANGE_EVT );

      return ( ZDO_INITDEV_LEAVE_NOT_STARTED );   // Don't join - (one time).

    }

    // Trigger the network start

    ZDApp_NetworkInit( extendedDelay );

  }

  // set broadcast address mask to support broadcast filtering

  NLME_SetBroadcastFilter( ZDO_Config_Node_Descriptor.CapabilityFlags );

  return ( networkStateNV );

}

在這個函式中有一段程式碼值得我們特別注意：

#if defined ( NV_RESTORE )

  // Get Keypad directly to see if a reset nv is needed.

  // Hold down the SW_BYPASS_NV key (defined in OnBoard.h)

  // while booting to skip past NV Restore.

  if ( HalKeyRead() == SW_BYPASS_NV )

    networkStateNV = ZDO_INITDEV_NEW_NETWORK_STATE;

。。。

#endif

我們在以前的文章裡曾提到過，裝置在復位之後，之前的網路資訊就會丟失，那麼裝置將以全新的狀態組建或者加入到網路中，這在實際使用過程中非常不方便。很多的應用場景中都要求裝置能夠在復位後仍舊按照上次入網的狀態重新連線到網路中，Zstack也提供了實現該機制的方法。在工程的Options->C/C++ Complier->Preprocessor的Defined symbols中我們填入：NV_RESTORE。再回到剛才說到的程式碼中，程式會呼叫HalKeyRead()，來判斷SW5的狀態。如果SW5沒有被按下，程式會呼叫ZDApp_RestoreNetworkState，取出上一次儲存在flash中的網路狀態資訊，裝置將根據這些資訊重新連線到網路中；如果SW5被按下，那麼即便我們使用了NV_RESTORE，程式將呼叫NLME_InitNV()和NLME_SetDefaultNV()，清除之前儲存的網路資訊，然後以全新的狀態加入網路中。在完成以上操作之後，程式會呼叫ZDApp_NetworkInit函式，觸發ZDO_NETWORK_INIT事件。

void ZDApp_NetworkInit( uint16 delay )

{

  if ( delay )

  {

    // Wait awhile before starting the device

    osal_start_timerEx( ZDAppTaskID, ZDO_NETWORK_INIT, delay );

  }

  else

  {

    osal_set_event( ZDAppTaskID, ZDO_NETWORK_INIT );

  }