Zigbee Fragmentation on z-stack 2.5.0 using ZNP + ZAP model

I don't know about the ZNP side, but I might be able to help with the packet sniffer "Parse data too long" error. I was having the same issue with the sniffer, was able to correct it by editing the file

C:\Program Files\Texas Instruments\SmartRF Tools\Packet Sniffer\bin\general\plugin\zigbee\zigbee.plt

in a text editor. Find the value "Packet_length_parsed_data" and increase this value; I believe the default is 1500, I increased it to 1600 and that fixed the problems I was having with the sniffer.

Hope this helps!

Hello,

   I'm not using the ZAP (I prefer starting with the examples) and I've been able to send/receive messages of 600 Bytes without any errors. This is using the stock ZNP hex files. The fragmentation feature is cool but not really well documented. Below is the code I used to send the message. It's a wrapper method for AF_DATA_REQUEST_EXT. The API is a bit wanky, because if the message is long you don't include any data in the first AF_DATA_REQUEST_EXT message but instead only use AF_DATA_STORE messages as needed to get the whole message loaded. Both functions are included.

 

--Derek

 

 

---

#define AF_DATA_REQUEST_EXT_PAYLOAD_LEN  20
#define AF_DATA_REQUEST_EXT_SRSP_STATUS_FIELD   SRSP_PAYLOAD_START
/** Sends a message using extended messaging. This is more flexible and allows for long addressing.
@param destinationLongAddress If using short addressing then the first two bytes are the short address,
LSB first. Remaining 6 bytes are don't care. If using long addressing then this is the 8 byte MAC, and LSB first.
@param destinationAddressMode Either DESTINATION_ADDRESS_MODE_LONG or DESTINATION_ADDRESS_MODE_SHORT
@see afSendData for description of remaining fields.
@note a znpResult of 0xE9 (233d) means ZMacNoACK error
@return the transactionId used for this message, or NULL if znp error.
This can be used by higher levels for matching AF_DATA_CONFIRM messages received.
If znpResult != 0 then return value must not be used.

TODO since sendMessage() is called in a few different places here (including in afDataStore)
return a negative value to indicate where the error occurred.
*/
unsigned char afSendDataExtended(unsigned char destinationEndpoint, unsigned char sourceEndpoint,
                        unsigned char* destinationAddress, unsigned char destinationAddressMode,
                        unsigned int clusterId, unsigned char* data, unsigned int dataLength)
{
    if ((dataLength > AF_DATA_REQUEST_EXT_MAX_TOTAL_PAYLOAD_LENGTH) || (dataLength == 0))
    {
        znpResult = AF_ERROR_MESSAGE_EXCEEDS_MAX_LENGTH;
        return NULL;
    }
    if (clusterId == 0)
    {
        znpResult = -2000;
        return NULL;
    }
#ifdef AF_ZDO_VERBOSE    
    printf("Sending EXT %u bytes to endpoint %u from endpoint %u with cluster %u (%04X) at LONG Address ",
           dataLength, destinationEndpoint, sourceEndpoint, clusterId, clusterId);
    printHexBytes(destinationAddress, 8);
#endif 
    unsigned char transId = transactionSequenceNumber++;  //this value will get returned for use by higher level
    znpBuf[0] = AF_DATA_REQUEST_EXT_PAYLOAD_LEN + dataLength;
    znpBuf[1] = MSB(AF_DATA_REQUEST_EXT);
    znpBuf[2] = LSB(AF_DATA_REQUEST_EXT);     
    znpBuf[3] = destinationAddressMode;
    if (destinationAddressMode == DESTINATION_ADDRESS_MODE_LONG)
    {
        memcpy(znpBuf+4, destinationAddress, 8);
    } else if (destinationAddressMode == DESTINATION_ADDRESS_MODE_SHORT) {
        memcpy(znpBuf+4, destinationAddress, 2);  //remaining bytes are don't care
    } else {        //error - unsupported addressing mode
        znpResult = -3;
        return NULL;
    }
    znpBuf[12] = destinationEndpoint;
    znpBuf[13] = LSB(INTRA_PAN);
    znpBuf[14] = MSB(INTRA_PAN);
    znpBuf[15] = sourceEndpoint;
    znpBuf[16] = LSB(clusterId);
    znpBuf[17] = MSB(clusterId);
    znpBuf[18] = transId;
    znpBuf[19] = 0; //MAC_ACK; //Could also use AF_APS_ACK;
    znpBuf[20] = DEFAULT_RADIUS;
    znpBuf[21] = LSB(dataLength);
    znpBuf[22] = MSB(dataLength);

    if (dataLength <= AF_DATA_REQUEST_EXT_MAX_PAYLOAD_LENGTH)                       //if payload short enough, then include it in this message
    {
        memcpy(znpBuf+AF_DATA_REQUEST_EXT_PAYLOAD_LEN+3, data, dataLength);
       
        //printZnpBuf();
       
        znpResult = sendMessage();                                                  //...and send the message
        if (znpResult != 0)
            return NULL; //if error then return immediately; don't wait for AF_DATA_CONFIRM
#ifdef AF_DATA_CONFIRM_HANDLED_BY_APPLICATION
    znpResult = 0;
#else
    znpResult = waitForMessage(AF_DATA_CONFIRM, AF_DATA_CONFIRM_TIMEOUT);
    if (znpResult != 0)
        return NULL;
    znpResult = znpBuf[AF_DATA_REQUEST_EXT_SRSP_STATUS_FIELD];      // verify status is success, pass error to calling method
#endif
    return transId;  //all done!
    }
   
    //NOW, message was larger than could fit into one message, so send the AF_DATA_REQUEST_EXT and then store the data...
    znpResult = sendMessage();
    if (znpResult != 0)
        return NULL;
   
    unsigned int totalMessageIndex = 0;  //index in the ZNP data buffer
   
    while (dataLength > 0)              //while there is still more data to be stored...
    {
        unsigned char bytesToSend = 0;
        if (dataLength > MAXIMUM_DATA_STORE_PAYLOAD_LENGTH)
            bytesToSend = MAXIMUM_DATA_STORE_PAYLOAD_LENGTH;
        else
            bytesToSend = dataLength;
       
        afDataStore(totalMessageIndex, data, bytesToSend);  //store each chunk of the total message
        if (znpResult != 0)
            return NULL;
       
        dataLength -= bytesToSend;
        totalMessageIndex += bytesToSend;      
#ifdef AF_ZDO_VERBOSE 
        printf("Sent %u Bytes, %u remaining\r\n", bytesToSend, dataLength);
#endif
    }

    afDataStore(0, data, 0);    //all data has been stored, now send the message
    if (znpResult != 0)
        return NULL;
#ifdef AF_DATA_CONFIRM_HANDLED_BY_APPLICATION
    znpResult = 0;
#else
    znpResult = waitForMessage(AF_DATA_CONFIRM, AF_DATA_CONFIRM_TIMEOUT);
#endif
    return transId;  //all done!
}

 

 

---

 

#define MAXIMUM_DATA_STORE_PAYLOAD_LENGTH 247
#define AF_DATA_STORE_PAYLOAD_LEN           3
void afDataStore(unsigned int index, unsigned char* data, unsigned char dataLength)
{
    if (dataLength > MAXIMUM_DATA_STORE_PAYLOAD_LENGTH)
    {
        znpResult = AF_ERROR_MESSAGE_EXCEEDS_MAX_LENGTH;
        return;
    }   
#ifdef AF_ZDO_VERBOSE    
    printf("Storing %u bytes starting at index %u\r\n", dataLength, index);
#endif
    // AF_DATA_STORE
    znpBuf[0] = AF_DATA_STORE_PAYLOAD_LEN + dataLength;
    znpBuf[1] = MSB(AF_DATA_STORE);
    znpBuf[2] = LSB(AF_DATA_STORE); 
   
    znpBuf[3] = LSB(index);
    znpBuf[4] = MSB(index);
    znpBuf[5] = dataLength;
    memcpy(znpBuf+AF_DATA_STORE_PAYLOAD_LEN+3, data, dataLength);
    znpResult = sendMessage();
    if (znpResult != 0)
        return;   
}

Hi I am using the IF_DATA_REQUEST_EXT to send messages between 112 and 200 bytes from my end device and my coordinator. It works fine, but if I turn down my coordinator the end device keeps sending messages and the value of the SRSP is Success, is this normal?.

I mean, is there any way to know that the coordinator  received the message from the END DEVICE side?

Thank you, I know it is not a really complicated question but I am new.

Jaime.

Hi , I am using the AF_DATA_STORE to send a message of 249 bytes and all seems to work fine but I don´t receive the AF_DATA_CONFIRM and the message never arrive to the coordinator. I don´t know if I must do something that is not here in the post . If I send a message using only AF_DATA_REQUEST_EXT it works fine so maybe I am missing something.

Hi Harry thank you for your fast reply.

I have downloaded the the file and I have seen the function you say. But I am not using the ZAP I am with the examples as Dereck. And I wonder If i can use the function he uses, but for me is not working. Another issue I have now is that I send the message with afSendDataExtended function in my end device side, but in my coordinator side I receive AF_INCOMING_MSG as AREQ instead of AF_INCOMING_MSG_EXT. I really can´t understand why.