一、简介
本文介绍在应用层如何开启广播,且解析协议栈在此操作后做了什么。
二、实验平台
协议栈版本:BLE-CC254x-1.4.0
编译软件:IAR 8.20.2
硬件平台:Amart RF开发板(主芯片CC2541)
三、版权声明
博主:甜甜的大香瓜
声明:喝水不忘挖井人,转载请注明出处。
原文地址:http://blog.csdn.NET/feilusia
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实验步骤
1、开启广播(simpleBLEPeripheral.c的SimpleBLEPeripheral_Init中)
在应用层开启广播功能其实非常简单,只要把TRUE传给GAPRole_SetParameter函数中的GAPROLE_ADVERT_ENABLED就可以了。
gaoyang9992006:
解析协议栈在开启广播的操作后做了什么 1、GAPRole_SetParameter函数中的GAPROLE_ADVERT_ENABLED
case GAPROLE_ADVERT_ENABLED:if ( len == sizeof( uint8 ) ){uint8 oldAdvEnabled = gapRole_AdvEnabled;gapRole_AdvEnabled = *((uint8*)pValue);if ( (oldAdvEnabled) && (gapRole_AdvEnabled == FALSE) ){// Turn off Advertisingif ( gapRole_state == GAPROLE_ADVERTISING ){VOID GAP_EndDiscoverable( gapRole_TaskID );}}else if ( (oldAdvEnabled == FALSE) && (gapRole_AdvEnabled) ){// Turn on Advertisingif ( (gapRole_state == GAPROLE_STARTED)|| (gapRole_state == GAPROLE_WAITING)|| (gapRole_state == GAPROLE_WAITING_AFTER_TIMEOUT) ){VOID osal_set_event( gapRole_TaskID, START_ADVERTISING_EVT );}}}else{ret = bleInvalidRange;}break;其中gapRole_AdvEnabled默认是TRUE
static uint8 gapRole_AdvEnabled = TRUE;
首先,每次进到这个函数里,就会把gapRole_AdvEnabled的值保存到oldAdvEnabled,再把新的状态写到gapRole_AdvEnabled。也就是这两句:
uint8 oldAdvEnabled = gapRole_AdvEnabled; gapRole_AdvEnabled = *((uint8*)pValue);
其次,对oldAdvEnabled(旧的广播开关状态)和gapRole_AdvEnabled(新传入的广播开关状态)这两个变量进行了判断:
1)在广播状态下,想关闭广播—–>关闭广播
2)在不广播的状态下,想开启广播—>开启广播
然而代码中并没有将另外两种情况编写进来,也就是
3)在广播状态下,还想开启广播
4)在不广播的状态下,还想关闭广播
协议栈把这两种情况划入了else的bleInvalidRange。
第2)种情况的开广播,调用了gapRole_TaskID任务中的START_ADVERTISING_EVT事件。
else if ( (oldAdvEnabled == FALSE) && (gapRole_AdvEnabled) ) { // Turn on Advertising if ( (gapRole_state == GAPROLE_STARTED) || (gapRole_state == GAPROLE_WAITING) || (gapRole_state == GAPROLE_WAITING_AFTER_TIMEOUT) ) { VOID osal_set_event( gapRole_TaskID, START_ADVERTISING_EVT ); } }
2、START_ADVERTISING_EVT事件
if ( events & START_ADVERTISING_EVT ){if ( gapRole_AdvEnabled ){gapAdvertisingParams_t params;// Setup advertisement parametersparams.eventType = gapRole_AdvEventType;params.initiatorAddrType = gapRole_AdvDirectType;VOID osal_memcpy( params.initiatorAddr, gapRole_AdvDirectAddr, B_ADDR_LEN );params.channelMap = gapRole_AdvChanMap;params.filterPolicy = gapRole_AdvFilterPolicy;if ( GAP_MakeDiscoverable( gapRole_TaskID, ¶ms ) != SUCCESS ){gapRole_state = GAPROLE_ERROR;// Notify the application with the new state changeif ( pGapRoles_AppCGs && pGapRoles_AppCGs->pfnStateChange ){pGapRoles_AppCGs->pfnStateChange( gapRole_state );}}}return ( events ^ START_ADVERTISING_EVT );}事件中调用GAP_MakeDiscoverable即可开启广播。
如果广播不成功,则会调用函数指针pGapRoles_AppCGs指向的回调函数,并且传入参数GAPROLE_ERROR,以此来通知应用层广播不成功。
gaoyang9992006:
回复 gaoyang9992006:
那么调用的又是哪个回调函数呢?
追踪一下pGapRoles_AppCGs发现有个注册回调函数的函数
/********************************************************************** @briefDoes the device initialization.** Public function defined in peripheral.h.*/ bStatus_t GAPRole_StartDevice( gapRolesCBs_t *pAppCallbacks ) {if ( gapRole_state == GAPROLE_INIT ){// Clear all of the Application callbacksif ( pAppCallbacks ){pGapRoles_AppCGs = pAppCallbacks;}// Start the GAPgapRole_SetupGAP();return ( SUCCESS );}else{return ( bleAlreadyInRequestedMode );} }再追踪一下这个注册函数,发现在应用层的SBP_START_DEVICE_EVT事件中对此进行了注册
if ( events & SBP_START_DEVICE_EVT ){// Start the DeviceVOID GAPRole_StartDevice( &simpleBLEPeripheral_PeripheralCBs );// Start Bond ManagerVOID GAPBondMgr_Register( &simpleBLEPeripheral_BondMgrCBs );// Set timer for first periodic eventosal_start_timerEx( simpleBLEPeripheral_TaskID, SBP_PERIODIC_EVT, SBP_PERIODIC_EVT_PERIOD );return ( events ^ SBP_START_DEVICE_EVT );}所以当广播开启不成功之后,会调用simpleBLEPeripheral_PeripheralCBs的回调函数peripheralStateNotificationCB的GAPROLE_ERROR
// GAP Role Callbacks static gapRolesCBs_t simpleBLEPeripheral_PeripheralCBs = {peripheralStateNotificationCB,// Profile State Change CallbacksNULL// When a valid RSSI is read from controller (not used by application) };case GAPROLE_ERROR:{#if (defined HAL_LCD) && (HAL_LCD == TRUE)HalLcdWriteString( "Error",HAL_LCD_LINE_3 );#endif // (defined HAL_LCD) && (HAL_LCD == TRUE)}break;case GAPROLE_ERROR:{#if (defined HAL_LCD) && (HAL_LCD == TRUE)HalLcdWriteString( "Error",HAL_LCD_LINE_3 );#endif // (defined HAL_LCD) && (HAL_LCD == TRUE)}break;到此,广播过程就结束了,很简单吧,哈哈。
Viki Shi:
回复 gaoyang9992006:
很不错的分享,赞