On Tuesday 18 July 2006 22:57, Trent Piepho wrote: > On Tue, 18 Jul 2006, Andrew de Quincey wrote: > > On Tuesday 18 July 2006 05:32, Trent Piepho wrote: > > > On Sun, 16 Jul 2006, Robert Schlabbach wrote: > > > > From: "Andrew de Quincey" <adq_dvb@xxxxxxxxxxxxx> > > > > > > > > > 1) One tuner needs to send 5 bytes. > > > > > I think this problem has been seen with other tuners too. > > > > > > > > You don't have to send 5 bytes. You can split the operation up. In > > > > fact, most of the time you won't have to change all PLL settings > > > > anyway (e.g. you can leave the AGC TOP setting unchanged after > > > > initialization), so sending 4 bytes will still suffice... In fact, it > > > > won't only suffice, but also save time & CPU cycles to write only the > > > > PLL registrs which you actually need to change. > > > > > > Did you read this thread on the dvb list? > > > http://www.linuxtv.org/pipermail/linux-dvb/2006-July/011583.html > > > > > > It's also about the agc top settings. I would hate to see too much > > > work done which has failed to consider the points already discussed. > > > > Yes I am remembering about that. I've decided to wait till I get to that > > part in the tuner refactoring before attempting to deal with it though. > > Right now I removed the 5byte stuff 'cos it isn't needed (in the ones I > > have done _so far_). Obviously it needs reconsidered when its needed. > > Keep in mind that the agc top needs to be re-programmed when the PLL is > initialized, and when changing from analog to digital mode. There is no > way to detect the latter condition now, so it is done on every tune. OK, thats pretty much what I figured really. > > Do you have the docs for the LG-H06xF and Thomson DTT761x so I can see > > the situation for myself? > > No, those docs doesn't appear to be available. You can get the docs to the > Infineon TUA603x PLL chips, which will tell you alot about what is going > on. > > If you read that thread, you will see that I did some tests to see what > effect the agc top setting has on the DTT7612. I will read it later, thanks for pointing me at it. > > mode 5th byte so the tuner would always be in the correct mode? On these > > cards I assume v4l+dvb cannot be both active at the same time... whats > > the mechanism for deciding which? > > They can both be active at once. It will even work fine if you use > different inputs. For example, capturing an analog signal connected to the > S-Video port and a digital signal from the tuner at the same time works. > You can use a VCR to turn it into a pseudo-dual tuner card, one analog > tuner, one digital tuner. Or instead of a VCR, a digital STB controlled by > an IR transmitter that can get encrypted channels. > > You can try to use the tuner from both v4l and dvb at the same time. They > will just play tug of war over it. I don't know why you would want to do > it, but it can be done. Ah I see - so one of them would tune it one way and the other the other. I was pretty convinced already we needed the 5byte thing, this just proves it. Thanks for explaining the situation completely. _______________________________________________ linux-dvb@xxxxxxxxxxx http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
