Francesco Schiavarelli wrote: > Manu Abraham wrote: >> Francesco Schiavarelli wrote: >>> Manu Abraham wrote: >>>> I guess it uses FEC short Frames and a Rolloff of 20%. >>>> Currently we use FEC normal frames and a Rolloff of 35%. I will check >>>> on this though. >>> Do you mean Rolloff and FEC type are somehow hardcoded in current >>> linuxtv STB0899 driver? >> >> Currently with CCM, we never had to worry about FEC long or short >> frames as it is always normal (LONG) frames with regards to CCM. >> >> The STB0899 driver doesn't take rolloff as a parameter from either >> from the user in the form of the S2 delivery system descriptor, or >> from a config file. >> >> It is in fact extracted from the Baseband header and used, thereby >> leading to "no" assumptions, in some cases the the SI can be wrong or >> missing, but the BaseBand header, not. So the STB0899 relies on a >> reliable method of extracting the rolloff and hence thereby the >> bandwidth of the same. > > Thanks for the clarification. > >>> If needed I can ask and provide here more detailed transmission >>> parameters regarding this transponder... >> >> This would be great, much appreciated. >> >>>> It looks like a DSNG profile, some uplinks as far as i can guess. >>> I can confirm that this feed will be used by local terrestrial DVB-T >>> transmitters, if I understand correctly your guessing. >> >> Yes, that is what i understand too. This profile uses ACM, well i need >> more inputs to have this implemented (ie this is currently an >> unimplemented feature, although it can be implemented) > > I don't think so. The signal I'm interested should use CCM, when asking > for more details I was pointed to EN 302 307 annex H.2 > Also ACM needs a return channel and I know for sure that in this case is > not used. > Ahh. I meant to write VCM, not ACM according to TR 102 376 Section: 5.2 In this case can you check whether the transmission is Hierarchial BC (Backward Compatible) or Layered BC ? Section 4.4. Layered BC mode doesn't exist on old satellites, but .. The reason being, why i am doubtful: if you used the STB0899, with Hierarchial BC mode you should have seen at least the HP stream. (scratching head) > Anyway ATM the feed is gone, but it should be up again next week with > some minor modification, when it's ready I'll keep you informed. I don't have access to that satellite, if you have a STB0899 based, you can try it, but before that you need to verify your setup works fine. Manu _______________________________________________ linux-dvb mailing list linux-dvb@xxxxxxxxxxx http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
