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Dumping raw DVB-S packets from satellite stream


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#1 boris_blackmilk

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Posted 10 October 2013 - 09:43

Hello all,

 

I am following the advice given on the OpenPLi development page, and introducing my project. Simply put, I would like to dump raw packets off a satellite stream using OpenPLi, dvbtune, dvbsnoop, and a program I have become aware of recently, syncfs, which is a time synchronised 9P connection.

 

For those not in the know, 9P is the native network/ file protocol of the operating system Plan 9.

 

Syncfs can be accessed at the following git:

 

https://github.com/geekmug/syncfs

 

The reason for this is I would like to remotely see raw packets come off the satellite stream in the efforts of understanding the DVB-S structure at a level that deals with the technique rather than simply watching the stream as a video stream. I have purchased a DM600PVR for this effort, and will be connecting it to a Linux workstation to examine the structure of the packets in (I hope) a human readable format.

 

Later on, I could use this knowledge for a two way DTV "whitespace" broadband link at around 400MHz to literally punch through dense foliage as encountered in heavily forested areas. For that system, I would be using a software defined radio like a BladeRF.

 

As an aside, I have previously held an amateur radio licence, and have a healthy interest in digital modulation techniques, in terms of structure and protocol. In some ways, a DM600PVR is a software receiver, it only does one modulation technique, but thats more than enough for my investigations at this point.

 

As for is this possible, I personally think so. All the software is available in source form, all I'd have to do is compile it for the DM600PVR. Thats why I'm here asking for details of where the actual source code for OpenPLi is stored (the git linked on the OpenPLi pages has only plugins unfortunately) and how I would go about logging in to the OpenPLi software running on my DM600PVR over the serial port, ie, a root console.

 

Many thanks in advance for any and all help given.

 

Shane.



Re: Dumping raw DVB-S packets from satellite stream #2 Sjaaky

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Posted 10 October 2013 - 15:50

The code for enigma1 receivers (ie dm7000, dm500, dm600pvr, dm7020) is here: http://sourceforge.n...code/HEAD/tree/ or if you want a direct svn url: https://svn.code.sf....p/openpli/code  ( trunk/cdk contains the interesting stuff ). But you can just take an image from our buildserver and install dvbsnoop on it. You can login to the dm600pvr by an ethernet connection with telnet. Use username root and password dream or dreambox (can't remember).

 

Tools like dvbsnoop let you view the raw mpeg-ts stream. I don't think you can get more raw than that. Note the mpeg-ts is encapsulated inside the DVB-S or DVB-S2 stream, but I know 99,999% certain that you cannot get to the DVB-S stream. In other words you cannot access the stream before it was is processed by the FEC for example.

I don't know how this will help you if you want to create bidirectional link for filesystem synchronization.




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