John,

Thanks for the attachments.

I think that "the async. nature of the msg-based blocks means there's no
back pressure on your vector_source block" was the problem.

Thanks again,
-George


On Tue, Feb 5, 2013 at 12:01 AM, John Malsbury <[email protected]>wrote:

> George,
>
> I don't have any hardware where I am, so I have the UHD source disabled.
> The speed (or lack there of) of the python block may be what is causing
> this issue.  It's also possible that the async. nature of the msg-based
> blocks means there's no back pressure on your vector_source block and it is
> generating samples as quickly as the cpu allows.  (anyone, chime in if you
> know better?)  When I insert a throttle before the stream to blob
> conversion, things seem to work OK.
>
> See attached.
>
> I've also attached another example for you to work with that has working
> mod and demod setup with a 'heartbeat' block that generates a periodic
> message.
>
> -John
>
>
>
>
> On Mon, Feb 4, 2013 at 8:28 PM, George Sklivanitis <
> [email protected]> wrote:
>
>> I am in v3.6.2.-3 and the problem still appears after removing the burst
>> gate.
>> Moreover, is there a way to test the data after the conversion of the
>> stream to blobs, either through Octave or Matlab (by connecting a file sink
>> at the flowgraph)?
>>
>> -George
>>
>> On Mon, Feb 4, 2013 at 11:23 PM, John Malsbury 
>> <[email protected]>wrote:
>>
>>> The file worked for me, but I'm testing with a machine with an older
>>> version of GNU Radio (3.6.2).  I will upgrade and retest.  In the meantime,
>>> can you remove the burst gate and tell me if the flowgraph runs without
>>> error?
>>>
>>> -John
>>>
>>>
>>> On Mon, Feb 4, 2013 at 8:06 PM, George Sklivanitis <
>>> [email protected]> wrote:
>>>
>>>> I am sorry, it was a typo.
>>>> The grc file generating the reported error is attached.
>>>>
>>>> -George
>>>>
>>>>
>>>> On Mon, Feb 4, 2013 at 10:58 PM, John Malsbury <[email protected]
>>>> > wrote:
>>>>
>>>>> ...   GMSK_mod  -> packet_framer -> multiplier -> Burst-Tag   ...
>>>>>
>>>>> the packet_framer should come before the modulator.  Not after.  Is
>>>>> this actually how it is connected or is there just a typo?
>>>>>
>>>>> Send me the GRC file.
>>>>>
>>>>>
>>>>>
>>>>> On Mon, Feb 4, 2013 at 7:54 PM, George Sklivanitis <
>>>>> [email protected]> wrote:
>>>>>
>>>>>>  Hi John,
>>>>>>
>>>>>> I suspected that this was where it has transferred. Though, by
>>>>>> installing pre-cog along with the extras and using
>>>>>> the packet_framing of precog instead of extras I get the following
>>>>>> error as I posted before,
>>>>>>
>>>>>> gr_fir_fff: using SSE
>>>>>> Uhandler caught exception: in method 
>>>>>> 'gr_block_gw_message_type_work_args_return_value_set',
>>>>>> argument 2 of type 'int'
>>>>>> Traceback (most recent call last):
>>>>>>   File 
>>>>>> "/usr/local/lib/python2.7/dist-packages/gnuradio/extras/block_gateway.py",
>>>>>> line 53, in eval
>>>>>>     try: self._callback()
>>>>>>   File 
>>>>>> "/usr/local/lib/python2.7/dist-packages/gnuradio/extras/block_gateway.py",
>>>>>> line 124, in __gr_block_handle
>>>>>>     ) for i in self.__out_indexes],
>>>>>> TypeError: in method 
>>>>>> 'gr_block_gw_message_type_work_args_return_value_set',
>>>>>> argument 2 of type 'int'
>>>>>> thread[thread-per-block[5]: <gr_block mod_pkts2 (3)>]: caught
>>>>>> unrecognized exception************
>>>>>>
>>>>>>
>>>>>> What is more, after replacing packet_framer with the framer of extras
>>>>>> repo, by trying to simulate
>>>>>> only the PHY level of precog
>>>>>>
>>>>>> transmitter
>>>>>>  (Vector_source -> stream_to_blob -> GMSK_mod  -> packet_framer ->
>>>>>> multiplier -> Burst-Tag -> USRP_sink)
>>>>>>
>>>>>> and on the other side
>>>>>> receiver:
>>>>>> (USRP_source -> packet_deframer -> GMSK_demod -> blob_to_s)
>>>>>>
>>>>>>
>>>>>> On 2/4/13 10:42 PM, John Malsbury wrote:
>>>>>>
>>>>>> https://github.com/jmalsbury/pre-cog<https://github.com/buoyboy/pre-cog>
>>>>>>
>>>>>> On Mon, Feb 4, 2013 at 7:41 PM, George Sklivanitis <
>>>>>> [email protected]> wrote:
>>>>>>
>>>>>>> Hello guys,
>>>>>>>
>>>>>>>  Is https://github.com/buoyboy/pre-cog down
>>>>>>> or I am the only one not being able to have access?
>>>>>>>
>>>>>>>  -George
>>>>>>>
>>>>>>>  --
>>>>>>> Sklivanitis Georgios
>>>>>>> Postgraduate Student
>>>>>>>
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> Discuss-gnuradio mailing list
>>>>>>> [email protected]
>>>>>>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Sklivanitis Georgios
>>>>>> Ph.D Student
>>>>>> Communications Division,
>>>>>> Department of Electronics and Electrical Engineering
>>>>>> University at Buffalo, The State University of New York
>>>>>> North Campus, Office 205, Furnas Hall
>>>>>> Buffalo, NY 14260www.acsu.buffalo.edu/~gsklivan 
>>>>>> <http://www.acsu.buffalo.edu/%7Egsklivan>
>>>>>>
>>>>>>
>>>>>
>>>>
>>>>
>>>> --
>>>> Sklivanitis Georgios
>>>> Postgraduate Student
>>>> Telecommunications Division
>>>> Technical University of Crete
>>>> ECE Dept.
>>>> Tel. : 28210 59257
>>>>
>>>
>>>
>>
>>
>> --
>> Sklivanitis Georgios
>> Postgraduate Student
>> Telecommunications Division
>> Technical University of Crete
>> ECE Dept.
>> Tel. : 28210 59257
>>
>
>


-- 
Sklivanitis Georgios
Postgraduate Student
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