ZigBee 设置信道、PANID、发射功率

现对z-stack里几个网络参数的设置以及如何获取总结一下。

信道配置：

Zigbee在3个频段定义了27个物理信道：868MHz频段中定义了1个信道，915MHz频段中定义了10个信道，信道间隔为2MHz，2.4GHz频段上定义了16个信道，信道间隔为5MHz。

信道编号	中心频率/MHz	信道间隔/MHz	频率上限/MHz	频率下限/MHz
k=0	868.3	--	868.6	868.0
k=1,2,…,10	906+2(k-1)	2	928.0	902．0
k=11,12,…,26	2401+5(k-11)	5	2483.5	2400.0

Z-stack中可以在f8wConfig.cfg里设置信道，相关部分如下：

/* Default channel is Channel 11 - 0x0B */

// Channels are defined in the following:

//         0      : 868 MHz     0x00000001

//         1 - 10 : 915 MHz     0x000007FE

//        11 - 26 : 2.4 GHz     0x07FFF800

//

//-DMAX_CHANNELS_868MHZ     0x00000001

//-DMAX_CHANNELS_915MHZ     0x000007FE

//-DMAX_CHANNELS_24GHZ      0x07FFF800

//-DDEFAULT_CHANLIST=0x04000000 // 26 - 0x1A

//-DDEFAULT_CHANLIST=0x02000000 // 25 - 0x19

//-DDEFAULT_CHANLIST=0x01000000 // 24 - 0x18

//-DDEFAULT_CHANLIST=0x00800000 // 23 - 0x17

//-DDEFAULT_CHANLIST=0x00400000 // 22 - 0x16

//-DDEFAULT_CHANLIST=0x00200000 // 21 - 0x15

//-DDEFAULT_CHANLIST=0x00100000 // 20 - 0x14

//-DDEFAULT_CHANLIST=0x00080000 // 19 - 0x13

//-DDEFAULT_CHANLIST=0x00040000 // 18 - 0x12

//-DDEFAULT_CHANLIST=0x00020000 // 17 - 0x11

//-DDEFAULT_CHANLIST=0x00010000 // 16 - 0x10

//-DDEFAULT_CHANLIST=0x00008000 // 15 - 0x0F

//-DDEFAULT_CHANLIST=0x00004000 // 14 - 0x0E

//-DDEFAULT_CHANLIST=0x00002000 // 13 - 0x0D

//-DDEFAULT_CHANLIST=0x00001000 // 12 - 0x0C

-DDEFAULT_CHANLIST=0x00000800 // 11 - 0x0B    这里默认使用的是编号为11的信道

当建网过程开始后，网络层将请求MAC层对规定的信道或由物理层默认的有效信道进行能量检测扫描，以检测可能的干扰。网络层管理实体对能量扫描的结果以递增的方式排序，丢弃那些能量值超出可允许能量水平的信道，然后再由网络层管理实体执行一次主动扫描，结合检查PAN描述符，对剩下的信道选择一个合适的建立网络。

若要在应用中查看信道，可以这样获得，_NIB.nwkLogicalChannel，读取这个就OK了。（NIB -NWK Information base-. 其中包含一些网络属性 PANID ,NETWORK ADDRESS 等等。其中_nib.nwkpanID是本网的ID标识，_NIB.extendedPANID按照字面意思是外网ID）

PANID:

在确定信道以后，下一步将是确定PANID，如果ZDAPP_CONFIG_PAN_ID被定义为0xFFFF，那么协调器将根据自身的IEEE地址建立一个随机的PANID（0～0x3FFF），如ZDAPP_CONFIG_PAN_ID没有被定义为0xFFFF，那么网络的PANID将由ZDAPP_CONFIG_PAN_ID确定。

“如果ZDAPP_CONFIG_PAN_ID被定义为0xFFFF，那么协调器将根据自身的IEEE地址建立一个随机的PANID（0～0x3FFF）”这句话怎么理解呢，我经过试验发现，这个随机的PANID并非完全随机，它有规律，与IEEE地址有一定的关系：要么就是IEEE地址的低16位，要么就是一个与IEEE地址低16位非常相似的值。如IEEE地址为0x8877665544332211，PANID很有可能就是2211，或相似的值；IEEE地址为0x8877665544337777，PANID很有可能就是3777，或其它相似的值；

Z-stack中相关部分代码如下：

/* Define the default PAN ID.

*

* Setting this to a value other than 0xFFFF causes

* ZDO_COORD to use this value as its PAN ID and

* Routers and end devices to join PAN with this ID

*/

-DZDAPP_CONFIG_PAN_ID=0xFFFF

若要在应用中查看PANID可以这样获得，_NIB.nwkPanId，读取这个就OK了。

发射功率：

传送范围的大小是和发射功率还有信道环境有关, 传送速率和传送范围之间没有直接联系。所以呢，适当的增大发射功率可增大传送范围。但也是有一定的限制的。具体详见datasheet。

在mac_radio_def.h里有可以设置：

#define MAC_RADIO_CHANNEL_DEFAULT               11

#define MAC_RADIO_TX_POWER_DEFAULT              0x1F

#define MAC_RADIO_TX_POWER_MAX_MINUS_DBM        25

这些只是举例说明一下，这些参数的意义，以及在z-stack里的什么地方修改。还有很多其它的参数，可以查看相关的源文件。

［mac_radio_def.h］

#define MAC_RADIO_SET_CHANNEL(x)            st( FSCTRLL = FREQ_2405MHZ + 5 * ((x) - 11); )

#define MAC_RADIO_SET_TX_POWER(x)            st( TXCTRLL = x; )

#define MAC_RADIO_SET_PAN_ID(x)              st( PANIDL = (x) & 0xFF; PANIDH = (x) >> 8; )

［mac_radio.c］

void macRadioInit(void)

{

/* variable initialization for this module */

reqChannel    = MAC_RADIO_CHANNEL_DEFAULT;

macPhyChannel = MAC_RADIO_CHANNEL_DEFAULT;

reqTxPower    = MAC_RADIO_TX_POWER_DEFAULT;

macPhyTxPower = MAC_RADIO_TX_POWER_DEFAULT;

}

［mac_low_level.h］

uint8 macRadioRandomByte(void);

void macRadioSetPanCoordinator(uint8 panCoordinator);

void macRadioSetPanID(uint16 panID);

void macRadioSetShortAddr(uint16 shortAddr);

void macRadioSetIEEEAddr(uint8 * pIEEEAddr);

void macRadioSetTxPower(uint8 txPower);

void macRadioSetChannel(uint8 channel);

void macRadioStartScan(uint8 scanType);

void macRadioStopScan(void);

void macRadioEnergyDetectStart(void);

uint8 macRadioEnergyDetectStop(void);

设置发射功率：

CC2530 设置RF的发送功率寄存器为TXPOWER，全局搜索一下可以看到以下代码

 #define MAC_RADIO_SET_PAN_COORDINATOR(b)              st( FRMFILT0 = (FRMFILT0 & ~PAN_COORDINATOR) | (PAN_COORDINATOR * (b!=0)); )
 #define MAC_RADIO_SET_CHANNEL(x)                      st( FREQCTRL = FREQ_2405MHZ + 5 * ((x) - 11); )
 #define MAC_RADIO_SET_TX_POWER(x)                     st( TXPOWER = x; )

 #define MAC_RADIO_SET_PAN_ID(x)                       st( PAN_ID0 = (x) & 0xFF; PAN_ID1 = (x) >> 8; )
 #define MAC_RADIO_SET_SHORT_ADDR(x)                   st( SHORT_ADDR0 = (x) & 0xFF; SHORT_ADDR1 = (x) >> 8; )

继续跟踪 MAC_RADIO_SET_TX_POWER

 /**************************************************************************************************
 * @fn          macRadioUpdateTxPower
 *
 * @brief       Update the radio's transmit power if a new power level has been requested
 *
 * @param       reqTxPower - file scope variable that holds the last request power level
 *              macPhyTxPower - global variable that holds radio's set power level
 *
 * @return      none
 **************************************************************************************************
 */
 MAC_INTERNAL_API void macRadioUpdateTxPower(void)
 {
   halIntState_t  s;

   /*
    *  If the requested power setting is different from the actual radio setting,
    *  attempt to udpate to the new power setting.
    */
   HAL_ENTER_CRITICAL_SECTION(s);
   if (reqTxPower != macPhyTxPower)
   {
     /*
      *  Radio power cannot be updated when the radio is physically transmitting.
      *  If there is a possibility radio is transmitting, do not change the power
      *  setting.  This function will be called again after the current transmit
      *  completes.
      */
     if (!macRxOutgoingAckFlag && !MAC_TX_IS_PHYSICALLY_ACTIVE())
     {
       /*
        *  Set new power level;  update the shadow value and write
        *  the new value to the radio hardware.
        */
       macPhyTxPower = reqTxPower;
 "#ff0000">      MAC_RADIO_SET_TX_POWER(macPhyTxPower);
     }
   }
   HAL_EXIT_CRITICAL_SECTION(s);
 }

在这里我们可以看到TXPOWER的设置值实际上应该是reqTxOower，让我看一下reqTxOower在哪里设置吧，继续跟踪可以发现reqTxPower在函数MAC_INTERNAL_API uint8 macRadioSetTxPower(uint8 txPower)中得到更新，一路跟踪下去可以在函数uint8 MAC_MlmeSetReq(uint8 pibAttribute, void *pValue)看到以下代码

     case MAC_PHY_TRANSMIT_POWER:
       /* Legacy transmit power attribute */
 #if !defined HAL_MAC_USE_REGISTER_POWER_VALUES && \
   !defined HAL_PA_LNA && !defined HAL_PA_LNA_CC2590
       /* Legacy transmit power attribute value for CC2530 alone,
        * or runtime selection support build means a negative absolute value.
        * However, when used as register power values or
        * with HAL_PA_LNAxxx definition (without runtime selection)
        * the attribute value is not a negative absolute value. */
       macPib.phyTransmitPower = (uint8)(-(int8)macPib.phyTransmitPower);
 #endif /* !defined HAL_MAC_USE_REGISTER_POWER_VALUES && ... */
       /* pass through to next case -- do not break*/

 #endif /* MAC_OBSOLETE_PHY_TRANSMIT_POWER */

     case MAC_PHY_TRANSMIT_POWER_SIGNED:
       (void)macRadioSetTxPower(macPib.phyTransmitPower);
       break;

到这里为止Z-Stack发送功率的设置流程已经明确，但是我找遍Z-Stack的工程也没有找到调用uint8 MAC_MlmeSetReq(uint8 pibAttribute, void *pValue)的地方想来应该是封装在TI提供的LIB文件中了，
修改TXPOWER的方法有两种：一、在uint8 macRadioSetTxPower(uint8 txPower)函数中通过修改 macPib.phyTransmitPower = (uint8)(-(int8)macPib.phyTransmitPower);的值来修改TXPOWER参数，系统复位后将使用调用该函数设置发送功率。修改 macPib.phyTransmitPower = (uint8)(-(int8)macPib.phyTransmitPower);可以通过修改以下结构体中的红色部分来修改

 static CODE const macPib_t macPibDefaults =
 {
   54,                                         /* ackWaitDuration */
   FALSE,                                      /* associationPermit */
   TRUE,                                       /* autoRequest */
   FALSE,                                      /* battLifeExt */
   6,                                          /* battLifeExtPeriods */

   NULL,                                       /* *pMacBeaconPayload */
   0,                                          /* beaconPayloadLength */
   MAC_BO_NON_BEACON,                          /* beaconOrder */
   0,                                          /* beaconTxTime */
   0,                                          /* bsn */

   {0, SADDR_MODE_EXT},                        /* coordExtendedAddress */
   MAC_SHORT_ADDR_NONE,                        /* coordShortAddress */
   0,                                          /* dsn */
   FALSE,                                      /* gtsPermit */
   4,                                          /* maxCsmaBackoffs */

   3,                                          /* minBe */
   0xFFFF,                                     /* panId */
   FALSE,                                      /* promiscuousMode */
   FALSE,                                      /* rxOnWhenIdle */
   MAC_SHORT_ADDR_NONE,                        /* shortAddress */

   MAC_SO_NONE,                                /* superframeOrder */
   0x01F4,                                     /* transactionPersistenceTime */
   FALSE,                                      /* assocciatedPanCoord */
   5,                                          /* maxBe */
   1220,                                       /* maxFrameTotalWaitTime */

   3,                                          /* maxFrameRetries */
   32,                                         /* ResponseWaitTime */
   0,                                          /* syncSymbolOffset */
   TRUE,                                       /* timeStampSupported */
   FALSE,                                      /* securityEnabled */

   /* Proprietary */
 #if defined (HAL_PA_LNA)
   19,                                         /* phyTransmitPower for CC2591 */
 #elif defined (HAL_PA_LNA_CC2590)
   11,                                         /* phyTransmitPower for CC2590 */
 #else
 "color:#ff0000;">0,                                          /* phyTransmitPower without frontend */
 #endif
   MAC_CHAN_11,                                /* logicalChannel */
   {0, SADDR_MODE_EXT},                        /* extendedAddress */
   1,                                          /* altBe */
   MAC_BO_NON_BEACON,                          /* deviceBeaconOrder */
 };

该值可以再-22到3之间变化具体可以参考

 const uint8 CODE macRadioDefsTxPwrBare[] =
 {
   3,  /* tramsmit power level of the first entry */
   (uint8)(int8)-22, /* transmit power level of the last entry */
   /*   3 dBm */   0xF5,   /* characterized as  4.5 dBm in datasheet */    //0
   /*   2 dBm */   0xE5,   /* characterized as  2.5 dBm in datasheet */
   /*   1 dBm */   0xD5,   /* characterized as  1   dBm in datasheet */
   /*   0 dBm */   0xD5,   /* characterized as  1   dBm in datasheet */
   /*  -1 dBm */   0xC5,   /* characterized as -0.5 dBm in datasheet */
   /*  -2 dBm */   0xB5,   /* characterized as -1.5 dBm in datasheet */
   /*  -3 dBm */   0xA5,   /* characterized as -3   dBm in datasheet */
   /*  -4 dBm */   0x95,   /* characterized as -4   dBm in datasheet */
   /*  -5 dBm */   0x95,
   /*  -6 dBm */   0x85,   /* characterized as -6   dBm in datasheet */
   /*  -7 dBm */   0x85,
   /*  -8 dBm */   0x75,   /* characterized as -8   dBm in datasheet */
   /*  -9 dBm */   0x75,
   /* -10 dBm */   0x65,   /* characterized as -10  dBm in datasheet */
   /* -11 dBm */   0x65,
   /* -12 dBm */   0x55,   /* characterized as -12  dBm in datasheet */
   /* -13 dBm */   0x55,
   /* -14 dBm */   0x45,   /* characterized as -14  dBm in datasheet */
   /* -15 dBm */   0x45,
   /* -16 dBm */   0x35,   /* characterized as -16  dBm in datasheet */
   /* -17 dBm */   0x35,
   /* -18 dBm */   0x25,   /* characterized as -18  dBm in datasheet */
   /* -19 dBm */   0x25,
   /* -20 dBm */   0x15,   /* characterized as -20  dBm in datasheet */
   /* -21 dBm */   0x15,
   /* -22 dBm */   0x05    /* characterized as -22  dBm in datasheet */
 };

二、就是使用MT功能

 void MT_SysSetTxPower(uint8 *pBuf)
 {
   /* A local variable to hold the signed dBm value of TxPower that is being requested. */
   uint8 signed_dBm_of_TxPower_requeseted;

   /*
    * A local variable to hold the signed dBm value of TxPower that can be set which is closest to
    * the requested dBm value of TxPower, but which is also valid according to a complex set of
    * compile-time and run-time configuration which is interpreted by the macRadioSetTxPower()
    * function.
    */
   uint8 signed_dBm_of_TxPower_range_corrected;

   /* Parse the requested dBm from the RPC message. */
   signed_dBm_of_TxPower_requeseted = pBuf[MT_RPC_POS_DAT0];

   /*
    * MAC_MlmeSetReq() will store an out-of-range dBm parameter value into the NIB. So it is not
    * possible to learn the actual dBm value that will be set by invoking MACMlmeGetReq().
    * But this actual dBm value is a required return value in the SRSP to this SREQ. Therefore,
    * it is necessary to make this redundant pre-call to macRadioSetTxPower() here in order to run
    * the code that will properly constrain the requested dBm to a valid range based on both the
    * compile-time and the run-time configurations that affect the available valid ranges
    * (i.e. MAC_MlmeSetReq() itself will invoke for a second time the macRadioSetTxPower() function).
    */
 "#ff0000">  signed_dBm_of_TxPower_range_corrected = macRadioSetTxPower(signed_dBm_of_TxPower_requeseted);

   /*
    * Call the function to store the requested dBm in the MAC PIB and to set the TxPower as closely
    * as possible within the TxPower range that is valid for the compile-time and run-time
    * configuration.
    */
   (void)MAC_MlmeSetReq(MAC_PHY_TRANSMIT_POWER_SIGNED, &signed_dBm_of_TxPower_requeseted);

   /* Build and send back the response that includes the actual dBm TxPower that can be set. */
   MT_BuildAndSendZToolResponse(((uint8)MT_RPC_CMD_SRSP | (uint8)MT_RPC_SYS_SYS),
                                        MT_SYS_SET_TX_POWER, 1,
                                        &signed_dBm_of_TxPower_range_corrected);
 }