Thanks,

i've already seen that tutorial and yes, it works fine. The problem I am  
having is most likely somewhere deeper. I am using the hardware in-line  
security. I have specified the requested parameters for the SECCTRL  
registers so that they would add 4-byte CBC-MAC (using some specified key)  
to the message, but when I catch the message with the BS app, it overrides  
the last byte. I was thinking about deeper examination with the ListenRaw  
tool, but didn't get it working as expected. Is the BS/Listen app  
displaying all the received bytes?

Oh and I am specifying the the length of the message to send (via the  
AMSend.send()) to be the size of my payload data.

Filip

On Tue, 05 Feb 2013 18:11:36 +0100, Jan Hauer <[email protected]>  
wrote:

> Hi Filip,
>
> the structure of serial AM packets is explained here:
> http://docs.tinyos.net/tinywiki/index.php/Mote-PC_serial_communication_and_SerialForwarder#BaseStation_and_net.tinyos.tools.Listen
> About the last byte: check once more that you pass the correct payload
> length, because in the example it seems that msg len field is 3 (not
> 4).
>
> Jan
>
>
> On Tue, Feb 5, 2013 at 3:05 PM, Filip Jurnečka  
> <[email protected]> wrote:
>> Ok, I did that. I know the byte 80 is in fact my defined AM type. Now it
>> is still an open question for me why does the CBC-MAC override the last
>> byte in the packet?
>>
>> Best,
>> Filip Jurnecka
>>
>> On Tue, 05 Feb 2013 14:58:18 +0100, wasif masood <[email protected]>
>> wrote:
>>
>>> Checkout the CC2420 datasheet for details regarding the 802.15.4 header
>>> strucutre.
>>>
>>> On Tue, Feb 5, 2013 at 2:17 PM, Filip Jurnečka
>>> <[email protected]>wrote:
>>>
>>>> Hi there.
>>>>
>>>> I wonder how the packet delimiters work. Say I have two packets. If  
>>>> sent
>>>> normally, the BS app displays them as:
>>>> 00 FF FF 00 01 00 22 80
>>>> 00 FF FF 00 01 01 22 80 00
>>>>
>>>> Now I don't know what the first 00 is, but the next FFFF is the
>>>> broadcast
>>>> address, the 0001 should be my address, the next 00/01 defines the
>>>> length
>>>> of the packet data. What is the 22? What is the 80? Is it the  
>>>> delimiter
>>>> of
>>>> the data to follow? Obviously, the last 00 is the data sent.
>>>>
>>>> Now it gets more interesting, if I enable the in-line CBC-MAC with 4
>>>> bytes
>>>> output, I get the following.
>>>> 00 FF FF 00 01 03 22 B7 E2 4C FB
>>>> 00 FF FF 00 01 04 22 80 71 36 57 EE
>>>>
>>>> The question is mainly about the fact that the output is overriding  
>>>> the
>>>> last byte of the unauthenticated message, i.e. the delimiter or the
>>>> payload byte. Any ideas why and how to fix it?
>>>>
>>>> Best regards,
>>>> Filip Jurnecka
>>>> _______________________________________________
>>>> Tinyos-help mailing list
>>>> [email protected]
>>>> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
>>>>
>>>
>>>
>>
>> _______________________________________________
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