Re: [PATCH] Re: [PATCH] Multi protocol support (stage #1)

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Manu Abraham wrote:
Manu Abraham wrote:
christophpfister@xxxxxxxxxxx wrote:
2. How does the demod filter? Does it exact matching or intelligent matching? -> intelligent matching means that if we use SIS we get the whole stream -> exact matching means that we have to use MIS and the correct stream_id,
otherwise we don't receive anything
Both would be possible (because HP and LP are already distinguished by
different modcods), but again: We don't know.


See my other post.

Each stream is specific to a PLFrame (Physical Layer Frame) Now for the

Small correction.

The LP stream is specific to a PLFrame (Physical Layer Frame) In accordance to the figure F.1 in Annex F EN 302 307 p 55, The HP stream is always DVB-S. Now for the

<continue>

demod to identify which PLFrame you are interested in, you have to tell

demod to identify the PLFrame .. <continue> ..

it something. It doesn't have any magic to know what you want.

This field through which you tell the demod which PLFrame your are interested in, is through the ISI (Input Stream Identifier)


Thanks for raising this thought.

Manu



Now according to the figure F.1 the HP stream is DVB-S modulated and the LP stream is DVB_S2 modulated. In this case we can drop the SISMIS flag and just use the ISI for the LP stream.


So eventually all that any DVB-S2 demod should be interested in the dvbs2_params are

(1) modulation
(2) fec
(3) rolloff
(4) stream identifier
(5) scrambling sequence index (we don't need this for the stb0899, this can be used by others if supported by others)

Additionally we may provide the descrambled BBHEADER also which may be useful as information

(2) MATYPE 1 & 2 (2 bytes)



Ok, Thinking again..

we can move stream identifier and rolloff into MATYPE's 1 & 2 itself,
since in all cases it is there. So in that case only that MATYPE2 is no
longer onformational only. Which will look exactly like the spec. :-)


So that eventually it is

(1) modulation
(2) fec
(3) scrambling sequence index (we don't need this for the stb0899, this
can be used by others if supported by others) from the S2 satellite
delivery system descriptor
(4) MATYPE 1 & 2 (2 bytes)


Looks more compact.


Manu


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