Z-stack ——osal

• osal 启动流程

osal流程图

协调器工作流程

终端器工作流程

• z-stack中事件和任务的事件处理函数是如何联系的？？

zigbee协议栈中的三个重要的变量：

tasksCnt：任务的总个数

tasksEvents：指针变量，指向了事件表的首地址

tasksArr：数组（如下代码定义的），数组的每一项都是一个函数指针，指向了事件处理函数

const pTaskEventHandlerFn tasksArr[] = {
  macEventLoop,
  nwk_event_loop,
  Hal_ProcessEvent,
#if defined( MT_TASK )
  MT_ProcessEvent,
#endif
  APS_event_loop,
#if defined ( ZIGBEE_FRAGMENTATION )
  APSF_ProcessEvent,
#endif
  ZDApp_event_loop,
#if defined ( ZIGBEE_FREQ_AGILITY ) || defined ( ZIGBEE_PANID_CONFLICT )
  ZDNwkMgr_event_loop,
#endif
  SampleApp_ProcessEvent
};

• Z-stack的osal初始化与轮询操作原理介绍

osal_start_system轮询函数：（当然在进入这个函数之前要对系统进行初始化，初始化的目的主要是将所以任务的事件初始化为0）

void osal_start_system( void )
{
#if !defined ( ZBIT ) && !defined ( UBIT )
  for(;;)  // Forever Loop
#endif
  {
    uint8 idx = 0;

    osalTimeUpdate();
    Hal_ProcessPoll();  // This replaces MT_SerialPoll() and osal_check_timer().
    
    do {
      if (tasksEvents[idx])  // Task is highest priority that is ready.
      {
        break;
      }
    } while (++idx < tasksCnt);

    if (idx < tasksCnt)
    {
      uint16 events;
      halIntState_t intState;

      HAL_ENTER_CRITICAL_SECTION(intState);
      events = tasksEvents[idx];
      tasksEvents[idx] = 0;  // Clear the Events for this task.
      HAL_EXIT_CRITICAL_SECTION(intState);

      events = (tasksArr[idx])( idx, events );//函数指针，调用相应的事件函数处理，结合上面图一

      HAL_ENTER_CRITICAL_SECTION(intState);
      tasksEvents[idx] |= events;  // Add back unprocessed events to the current task.
      HAL_EXIT_CRITICAL_SECTION(intState);
    }
#if defined( POWER_SAVING )
    else  // Complete pass through all task events with no activity?
    {
      osal_pwrmgr_powerconserve();  // Put the processor/system into sleep
    }
#endif
  }
}

13-17行：循环查看事件表是否有事件发生（有就不为零，后跳出循环《可以结合上面图一来理解》）

25行     ：读取该事件。

29行     ：调用事件处理函数处理

• Z-stack sample applications 部分解析(from Z-Stack Sample Applications.pdf)

1. Task Initialization（任务初始化）

void SampleApp_Init( uint8 task_id )
{
  SampleApp_TaskID = task_id;
  SampleApp_NwkState = DEV_INIT;
  SampleApp_TransID = 0;//发送数据包的序号，在zigbee协议栈中，每发送一个数据包，该发送序号自动加1.作用：接收端来计算丢包率。

  // Device hardware initialization can be added here or in main() (Zmain.c).
  // If the hardware is application specific - add it here.
  // If the hardware is other parts of the device add it in main()

 #if defined ( BUILD_ALL_DEVICES )
  // The "Demo" target is setup to have BUILD_ALL_DEVICES and HOLD_AUTO_START
  // We are looking at a jumper (defined in SampleAppHw.c) to be jumpered
  // together - if they are - we will start up a coordinator. Otherwise,
  // the device will start as a router.
  if ( readCoordinatorJumper() )
    zgDeviceLogicalType = ZG_DEVICETYPE_COORDINATOR;
  else
    zgDeviceLogicalType = ZG_DEVICETYPE_ROUTER;
#endif // BUILD_ALL_DEVICES

#if defined ( HOLD_AUTO_START )
  // HOLD_AUTO_START is a compile option that will surpress ZDApp
  //  from starting the device and wait for the application to
  //  start the device.
  ZDOInitDevice(0);
#endif

  // Setup for the periodic message‘s destination address
  // Broadcast to everyone
  SampleApp_Periodic_DstAddr.addrMode = (afAddrMode_t)AddrBroadcast;
  SampleApp_Periodic_DstAddr.endPoint = SAMPLEAPP_ENDPOINT;
  SampleApp_Periodic_DstAddr.addr.shortAddr = 0xFFFF;

  // Setup for the flash command‘s destination address - Group 1
  SampleApp_Flash_DstAddr.addrMode = (afAddrMode_t)afAddrGroup;
  SampleApp_Flash_DstAddr.endPoint = SAMPLEAPP_ENDPOINT;
  SampleApp_Flash_DstAddr.addr.shortAddr = SAMPLEAPP_FLASH_GROUP;

  // Fill out the endpoint description.
  SampleApp_epDesc.endPoint = SAMPLEAPP_ENDPOINT;
  SampleApp_epDesc.task_id = &SampleApp_TaskID;
  SampleApp_epDesc.simpleDesc
            = (SimpleDescriptionFormat_t *)&SampleApp_SimpleDesc;
  SampleApp_epDesc.latencyReq = noLatencyReqs;

  // Register the endpoint description with the AF
  afRegister( &SampleApp_epDesc );

  // Register for all key events - This app will handle all key events
  RegisterForKeys( SampleApp_TaskID );

  // By default, all devices start out in Group 1
  SampleApp_Group.ID = 0x0001;
  osal_memcpy( SampleApp_Group.name, "Group 1", 7  );
  aps_AddGroup( SAMPLEAPP_ENDPOINT, &SampleApp_Group );

#if defined ( LCD_SUPPORTED )
  HalLcdWriteString( "SampleApp", HAL_LCD_LINE_1 );
#endif
}

代码3-38：初始化本地变量与应用程序对象等；

代码41-51：将应用程序对象注册到AF层（afRegister( &SampleApp_epDesc )）；登记注册到OSAL与HAL系统服务中（ RegisterForKeys( SampleApp_TaskID );）。只有注册后才可以使用OSAL提供的系统服务。

2.    Task Event Handler（任务处理）

uint16 SampleApp_ProcessEvent( uint8 task_id, uint16 events )
{
  afIncomingMSGPacket_t *MSGpkt;
  (void)task_id;  // Intentionally unreferenced parameter

  if ( events & SYS_EVENT_MSG )
  {
    MSGpkt = (afIncomingMSGPacket_t *)osal_msg_receive( SampleApp_TaskID );//从消息队列上接收消息
    while ( MSGpkt )
    {
      switch ( MSGpkt->hdr.event )
      {
        // Received when a key is pressed
        case KEY_CHANGE:
          SampleApp_HandleKeys( ((keyChange_t *)MSGpkt)->state, ((keyChange_t *)MSGpkt)->keys );
          break;

        // Received when a messages is received (OTA) for this endpoint
        case AF_INCOMING_MSG_CMD:
          SampleApp_MessageMSGCB( MSGpkt );
          break;

        // Received whenever the device changes state in the network
        case ZDO_STATE_CHANGE:
          SampleApp_NwkState = (devStates_t)(MSGpkt->hdr.status);
          if ( (SampleApp_NwkState == DEV_ZB_COORD)
              || (SampleApp_NwkState == DEV_ROUTER)
              || (SampleApp_NwkState == DEV_END_DEVICE) )
          {
            // Start sending the periodic message in a regular interval.
            osal_start_timerEx( SampleApp_TaskID,
                              SAMPLEAPP_SEND_PERIODIC_MSG_EVT,
                              SAMPLEAPP_SEND_PERIODIC_MSG_TIMEOUT );
          }
          else
          {
            // Device is no longer in the network
          }
          break;

        default:
          break;
      }

      // Release the memory
      osal_msg_deallocate( (uint8 *)MSGpkt );

      // Next - if one is available
      MSGpkt = (afIncomingMSGPacket_t *)osal_msg_receive( SampleApp_TaskID );// Get the next message
    }

    
/******************************************************
After processing the SYS_EVENT_MSG messages, 
the processing function should return the unprocessed
events:
*******************************************************/
    return (events ^ SYS_EVENT_MSG);// return unprocessed events
  }

  // Send a message out - This event is generated by a timer
  //  (setup in SampleApp_Init()).
  if ( events & SAMPLEAPP_SEND_PERIODIC_MSG_EVT )
  {
    // Send the periodic message
    SampleApp_SendPeriodicMessage();

    // Setup to send message again in normal period (+ a little jitter)
    osal_start_timerEx( SampleApp_TaskID, SAMPLEAPP_SEND_PERIODIC_MSG_EVT,
        (SAMPLEAPP_SEND_PERIODIC_MSG_TIMEOUT + (osal_rand() & 0x00FF)) );

    // return unprocessed events
    return (events ^ SAMPLEAPP_SEND_PERIODIC_MSG_EVT);
  }

  // Discard unknown events
  return 0;
}

当然这里的任务处理函数可以看到两大类任务：SYS_EVENT_MSG与SAMPLEAPP_SEND_PERIODIC_MSG_EVT

我的理解：（1）SYS_EVENT_MSG(0x8000)，是osal操作系统的系统等待轮询任务；一旦调用这个任务事件，

它必须得是以下子事件触发：AF_INCOMING_MSG_CMD ：来自其它设备AF层发送过来的消息事件

KEY_CHANGE：用户按键事件

ZDO_STATE_CHANGE ：网络状态变化事件

CMD_SERIAL_MSG：MT层串口发送过来的数据。（注意要加上MT.h头文件）

当然除了以上的Command IDs 外还有一些其它的。可以根据自己的应用需求而添加

（2）SAMPLEAPP_SEND_PERIODIC_MSG_EVT，定时器中断事件，要是需要定时或周期性的触发一些事件（比如周期发送消息）可以在此事件下面添加用户响应函数。

3. Message Flow（消息流）

AF_DataRequest（）；

来自为知笔记(Wiz)