1.5.1.2 Transmission

The MAC-RT PLC & Go application configures the default values of the MAC 802.15.4 header frame, updating the contents of the corresponding structure MAC_RT_HEADER (defined in drv_g3_macrt_comm.h file), during the initialization stage in the function APP_PLC_SetInitialConfiguration. Furthermore, the function APP_PLC_SetSourceAddress allows to set the source address (own short address), the function APP_PLC_SetDestinationAddress allows to set the destination address (unicast or broadcast short address) and the function APP_PLC_SetPANID allows to set the PAN ID.

static void APP_PLC_SetInitialConfiguration ( void )
{
    /* Apply PLC coupling configuration */
    SRV_PCOUP_Set_Config(appPlc.drvPlcHandle, appPlc.couplingBranch);

    /* Force Transmission to VLO mode by default in order to maximize signal level in any case */
    /* Disable auto-detect mode */
    appPlc.plcPIB.pib = MAC_RT_PIB_MANUF_PHY_PARAM;
    appPlc.plcPIB.index = PHY_PIB_CFG_AUTODETECT_IMPEDANCE;
    appPlc.plcPIB.length = 1;
    appPlc.plcPIB.pData[0] = 0;
    DRV_G3_MACRT_PIBSet(appPlc.drvPlcHandle, &appPlc.plcPIB);

    /* Set VLO mode */
    appPlc.plcPIB.index = PHY_PIB_CFG_IMPEDANCE;
    appPlc.plcPIB.length = 1;
    appPlc.plcPIB.pData[0] = 2;
    DRV_G3_MACRT_PIBSet(appPlc.drvPlcHandle, &appPlc.plcPIB);

    /* Get PLC PHY version */
    appPlc.plcPIB.index = PHY_PIB_VERSION_NUM;
    appPlc.plcPIB.length = 4;
    DRV_G3_MACRT_PIBGet(appPlc.drvPlcHandle, &appPlc.plcPIB);
    memcpy((uint8_t *)&appPlc.phyVersion, appPlc.plcPIB.pData, 4);
    
    /* Fill MAC RT Header */
    appPlcTx.txHeader.frameControl.frameType = MAC_RT_FRAME_TYPE_DATA;
    appPlcTx.txHeader.frameControl.securityEnabled = 0;
    appPlcTx.txHeader.frameControl.framePending = 0;
    appPlcTx.txHeader.frameControl.ackRequest = 0; // No en Broadcast
    appPlcTx.txHeader.frameControl.frameVersion = 1;
    appPlcTx.txHeader.sequenceNumber = 0;
    
    /* Set PAN_ID */
    APP_PLC_SetPANID(CONF_PAN_ID);
    
    /* Set Addresses */
    APP_PLC_SetDestinationAddress(MAC_RT_SHORT_ADDRESS_BROADCAST);
    APP_PLC_SetSourceAddress((uint16_t)TRNG_ReadData());

    if (appPlc.staticNotchingEnable)
    {
        /* Set Tone Mask (Static Notching) */
        appPlc.plcPIB.pib = MAC_RT_PIB_TONE_MASK;
        appPlc.plcPIB.index = 0;
        appPlc.plcPIB.length = sizeof(MAC_RT_TONE_MASK);
        memcpy(appPlc.plcPIB.pData, appPlcToneMask.toneMask, sizeof(MAC_RT_TONE_MASK));
        DRV_G3_MACRT_PIBSet(appPlc.drvPlcHandle, &appPlc.plcPIB);
    }
}

void APP_PLC_SetSourceAddress ( uint16_t address )
{
    /* Set Short Address in TX header */
    appPlcTx.txHeader.frameControl.srcAddressingMode = MAC_RT_SHORT_ADDRESS;
    appPlcTx.txHeader.sourceAddress.addressMode = MAC_RT_SHORT_ADDRESS;
    appPlcTx.txHeader.sourceAddress.shortAddress = address;
    
    /* Set Short Address in G3 MAC RT device */
    appPlc.plcPIB.pib = MAC_RT_PIB_SHORT_ADDRESS;
    appPlc.plcPIB.index = 0;
    appPlc.plcPIB.length = 2;
    memcpy(appPlc.plcPIB.pData, (uint8_t *)&address, 2);
    DRV_G3_MACRT_PIBSet(appPlc.drvPlcHandle, &appPlc.plcPIB);
}

void APP_PLC_SetDestinationAddress ( uint16_t address )
{
    /* Set Short Address in TX header */
    appPlcTx.txHeader.frameControl.destAddressingMode = MAC_RT_SHORT_ADDRESS;
    appPlcTx.txHeader.destinationAddress.addressMode = MAC_RT_SHORT_ADDRESS;
    appPlcTx.txHeader.destinationAddress.shortAddress = address;
}

void APP_PLC_SetPANID ( uint16_t panid )
{
    /* Set Short Address in TX header */
    appPlcTx.txHeader.frameControl.panIdCompression = 1;
    appPlcTx.txHeader.destinationPAN = panid;
    appPlcTx.txHeader.sourcePAN = panid;
    
    /* Set Short Address in G3 MAC RT device */
    appPlc.plcPIB.pib = MAC_RT_PIB_PAN_ID;
    appPlc.plcPIB.index = 0;
    appPlc.plcPIB.length = 2;
    memcpy(appPlc.plcPIB.pData, (uint8_t *)&panid, 2);
    DRV_G3_MACRT_PIBSet(appPlc.drvPlcHandle, &appPlc.plcPIB);
}

Once the transmission is configured, the function APP_PLC_SendData prepares the data to be sent through PLC, storing the MAC header and the data in the transmission buffer (appPlcTxFrameBuffer). The function APP_PLC_BuildMacRTHeader is used to build the MAC header and store it in the transmission buffer. When all the information is in the transmission buffer, the function DRV_G3_MACRT_TxRequest() is called to request the transmission of the PLC message.

static uint8_t APP_PLC_BuildMacRTHeader ( uint8_t *pFrame, MAC_RT_HEADER *pHeader )
{
    uint8_t *pData;
    
    pData = pFrame;
    
    /* Copy Frame Control and Sequence number */
    memcpy(pData, pHeader, 3);
    pData += 3;
    /* Build Header to use MAC_RT_SHORT_ADDRESS mode */
    /* Destination PAN ID */
    *pData++ = (uint8_t)(pHeader->destinationPAN);
    *pData++ = (uint8_t)(pHeader->destinationPAN >> 8);
    /* Destination address */
    *pData++ = (uint8_t)(pHeader->destinationAddress.shortAddress);
    *pData++ = (uint8_t)(pHeader->destinationAddress.shortAddress >> 8);
    /* panIdCompression = 1 -> No Source PAN ID */
    /* Source Address */
    *pData++ = (uint8_t)(pHeader->sourceAddress.shortAddress);
    *pData++ = (uint8_t)(pHeader->sourceAddress.shortAddress >> 8);
    
    /* Return Header length */
    return (uint8_t)(pData - pFrame);
}

bool APP_PLC_SendData ( uint8_t* pData, uint16_t length )
{
    if (appPlc.state == APP_PLC_STATE_WAITING)
    {
        if (appPlc.pvddMonTxEnable)
        {
            uint8_t *pFrame;
            uint8_t headerLen;
            
            if (length > MAC_RT_MAX_PAYLOAD_SIZE) {
                return false;
            }
            
            appPlc.plcTxState = APP_PLC_TX_STATE_WAIT_TX_CFM;
            
            pFrame = appPlcTx.pTxFrame;
            
            /* Build MAC RT Frame */
            headerLen = APP_PLC_BuildMacRTHeader(pFrame, &appPlcTx.txHeader);
            pFrame += headerLen;
            
            /* Fill Payload */
            memcpy(pFrame, pData, length);
            pFrame += length;

            /* Send MAC RT Frame */
            DRV_G3_MACRT_TxRequest(appPlc.drvPlcHandle, appPlcTx.pTxFrame, 
                    pFrame - appPlcTx.pTxFrame);

            /* Set PLC state */
            if (appPlc.plcTxState == APP_PLC_TX_STATE_WAIT_TX_CFM)
            {
                appPlc.state = APP_PLC_STATE_WAITING_TX_CFM;
                return true;
            }
        }
    }
    
    return false;
}