On Sat, May 13, 2006, Manu Abraham wrote: > Johannes Stezenbach wrote: > >The way I read the standard, the ACM return channel > >could be a telephone line or DSL/internet to the playout center. > >The demod hw would handle ACM receiption automatically, and an > >application would monitor signal quality and send commands back > >to the transmitter to change modulation and fec until it gets > >max throughput at good quality. > > Well, as i said, from the specs, again 6.1 has a nice picture how it is > done too .. I did _not_ say that the demod is having DVB-RCS capabilities. > > In any case, whatever mode is used the specs _says_ MODCOD is used. IMHO > MODCOD is necessary, eliminating modulation + coderate. I didn't say MODCOD is unnecessary. I did say it is unnecessary *in the Linux DVB API*. Because the API uses what it gets from the satellite_delivery_descriptor, which is FEC and modulation in two seperate fields. And we might provide MATYPE for informational purposes, but decoding it is left to the application. You could put the code to decode it into dvb-apps/lib/ somewhere. Please, if someone has different opinions, please let me know about it, and provide technical arguments to whow me where I am wrong. I do not claim to have full understanding of the DVB-S2 spec. I haven't even read all of it. Thanks, Johannes _______________________________________________ linux-dvb@xxxxxxxxxxx http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
