Johannes Stezenbach wrote:
On Thu, May 25, 2006, christophpfister@xxxxxxxxxxx wrote:
Johannes Stezenbach wrote:
-> this would mean that modulation and fec are the same
for DVB-S and DVB-S2
(however, thanks to the MODCOD field in the DVB-S2
PLHEADER it would probably work with different
mod/fec, too, as the demod can figure it out automatically)
Yes, But another rolloff may be used (in v1.5.1 there are reserved values
at #modulation which are used now).
(Indeed, I believe the modulation and fec fields in
struct dvbs2_params are not necessary -- the values
can change on a per-frame basis anyway, says the spec.)
They are necessary! It's possible that the transmitters sends more than one
stream (with VCM / TDM), but you have to specifiy the modcod for the stream
you want to receive.
In MIS mode both streams can have different mod/fec. However,
I don't see any per-stream_id mod/fec registers in the
STB0899 data sheet,
This is from the STB0899 spec
Stream filter mechanism
[..]
SIS/MIS (1 bit): describes whether there is a single input stream or
multiple input streams. If SIS/
MIS = multiple input stream, then the second byte is the input stream
identifier (ISI), otherwise
the second byte is reserved.
The stream filter can be handled by the I2C register where the MATYPE
register is forced.
and certainly you don't imply there's
an API call necessary per received frame to change the
settings?
No additional API calls. the calls are all defined in
http://linuxtv.org/hg/~manu/stb0899
Manu
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