Jay,

As it turns out I am working on an out-of-tree module to work with the
CC1101, which I think I'll be able to release.  The number of possible
formats for the frame are relatively few if you know they are using CRC and
you know the packets aren't fixed length. (use_sequence_number?,
use_address_field?).  By definition, we know there will be length field
since these are not fixed length packets.  It would probably just make
sense to test the handful of options until CRC passes.

Of course, this changes if the device isn't taking advantage of CC1101s
packet handling functionality, and instead the MCU is providing more than
just the "payload".  In such a case, there is potentially larger feature
space for the frame.

I'll let you know about the CC1101 OOT.

-John


On Wed, Apr 30, 2014 at 8:22 AM, Jay Radcliffe <jay.radcli...@gmail.com>wrote:

> Maybe I should rephrase: I don't know the entire protocol. I know there is
> a preamble, and I know the sync word.  I know the packets are not fixed
> length, I know there is a CRC. This can all be determined from looking at
> the register settings for the CC1101 chip.  The format of the data portion
> of transmission I do not know. In order to reverse that I need raw data for
> analysis.
>
> That is how I am handling it right now.  I stream the output of the
> Correlate Access Code to a file sink.  What is in that file though is data,
> not readable binary stream (or readable hex stream). What I want is tcpdump
> like output.
>
> Jay Radcliffe
> Twitter: @jradcliffe02
> E-Mail: jay.radcli...@gmail.com
> LinkedIn + Resume: http://www.linkedin.com/in/jradcliffe02
>
>
> On Wed, Apr 30, 2014 at 9:09 AM, John Malsbury <john.malsb...@ettus.com>wrote:
>
>> Jay,
>>
>> If you stream the output of the correlate access code to file, and you
>> leave them unpacked, Bit 1 being set will show where the sync word is (I
>> think the bit after).  Of course Bit 0 will be the data.  This assumes
>> you're using correlate access code, and not "correlate access code - tag".
>> This should allow you to store everything including the preamble.
>>
>> Also, if you don't know the protocol, how do you know what the preamble
>> is?
>>
>> -John
>>
>>
>> On Tue, Apr 29, 2014 at 1:43 PM, Jay Radcliffe 
>> <jay.radcli...@gmail.com>wrote:
>>
>>> The protocol is unknown at this time.  I need to see the packets to
>>> figure some of this out.
>>>
>>> Ideally, I would like to see the entire packet (including the preamble
>>> and sync word) to start to work my way to the format of the packets from
>>> there.  I am using the power squelch with the gate to limit the captures to
>>> just when a signal is over a certain strength. In a perfect world, I would
>>> like to have "Binary Slicer" -> "File Sink" where the file contents are the
>>> binary stream (10101010101010 not to be confused for a binary file) or hex
>>> output (0xAA 0xAA).  I could probably tag the preamble in with the
>>> Correlate Access Code?
>>>
>>> Jay Radcliffe
>>> Twitter: @jradcliffe02
>>> E-Mail: jay.radcli...@gmail.com
>>> LinkedIn + Resume: http://www.linkedin.com/in/jradcliffe02
>>>
>>>
>>> On Sun, Apr 27, 2014 at 9:28 PM, John Malsbury 
>>> <john.malsb...@ettus.com>wrote:
>>>
>>>> Jay,
>>>>
>>>> Thanks for the inquiry.  Is there a specific protocol or format you are
>>>> trying to work with?  Are the frame size fixed in length or variable?  The
>>>> answers to these questions will dictate whether you can use an existing
>>>> block or if you will need to write your own.
>>>>
>>>> Writing a block to parse things after the correlate access code block
>>>> is relatively straight-forward.  If you are using the (tag) version of that
>>>> block, you simply need to look for the presence of that tag to delineate
>>>> the start of a frame.
>>>>
>>>> -John
>>>>
>>>>
>>>> On Sun, Apr 27, 2014 at 4:27 PM, Jay Radcliffe <jay.radcli...@gmail.com
>>>> > wrote:
>>>>
>>>>> I have a question about handling data after binary slicing in the
>>>>> demodulation portion of handling a signal. Currently I am taking that data
>>>>> and pushing it through the Correlate Access Code block then into a file
>>>>> sink. This produces a data file.  I didn't know if someone could tell me a
>>>>> block or method that will output the binary stream (or hex stream) to a
>>>>> file or stdout for real-time view of the pack contents. Currently I have
>>>>> some python code that converts that data file into binary/hex which is not
>>>>> idea.
>>>>>
>>>>> Thanks,
>>>>>
>>>>> Jay
>>>>>
>>>>>
>>>>> Jay Radcliffe
>>>>> Twitter: @jradcliffe02
>>>>> E-Mail: 
>>>>> jay.radcli...@gmail.com<https://mail.google.com/mail/?view=cm&fs=1&tf=1&to=jay.radcli...@gmail.com>
>>>>> LinkedIn + Resume: http://www.linkedin.com/in/jradcliffe02
>>>>>
>>>>> _______________________________________________
>>>>> Discuss-gnuradio mailing list
>>>>> Discuss-gnuradio@gnu.org
>>>>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>>>>>
>>>>>
>>>>
>>>
>>
>
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