[linux-dvb] Tuning problems with loss of TS packets

Alex Betis alex.betis at gmail.com
Sat Feb 7 12:47:29 CET 2009


On Sat, Feb 7, 2009 at 12:57 PM, Josef Wolf <jw at raven.inka.de> wrote:

> On Sat, Feb 07, 2009 at 11:12:25AM +0200, Alex Betis wrote:
> [ ... ]
> > > To be precise: on an already set-up transponder, re-executing this
> > > function:
> > >
> > >  static void tune_frequency (int ifreq, int sr)
> > >  {
> > >      struct dvb_frontend_parameters tuneto;
> > >
> > >      tuneto.frequency = ifreq*1000;
> > >      tuneto.inversion = INVERSION_AUTO;
> > >      tuneto.u.qpsk.symbol_rate = sr*1000;
> > >      tuneto.u.qpsk.fec_inner = FEC_AUTO;
> > >
> > >      if (ioctl(fefd, FE_SET_FRONTEND, &tuneto) == -1) {
> > >          fatal ("FE_SET_FRONTEND failed: %s\n", strerror (errno));
> > >      }
> > >  }
> > >
> > > with _exactly_ the same values for ifreq and sr, is able to toggle from
> > > good TS stream to bad TS stream or vice-versa.  As long as I avoid to
> > > call this function, the quality of the stream does _not_ change.
> >
> > I had exactly the same behavior of Twinhan SP-200 (1027) card until I
> > totally gave up and bought Twinhan SP-400 (1041) card.
> > Interesting if those 2 cards have the same components.
>
> The cards I have are of those:
> http://www.linuxtv.org/wiki/index.php/TechnoTrend_PCline_budget_DVB-S
> Do you think the problem is related to hardware?


Since the tuning works from time to time, I tend to think that its a driver
problem.


>
>
> > > I have tried to use fixed values instead of *_AUTO for FEC and
> INVERSION,
> > > but that did not help either.
> > >
> > > Any ideas?
> >
> > What driver repository you use? And what driver is loaded for that card?
> > My guess was that the tuner is not properly reset/set before the tuning.
> > But (again) since I don't have any chip specification, I didn't have much
> > progress with that.
>
>  # lsmod|egrep '(dvb|budget|stv|saa|ttpci)'
>  stv0299                11280  1
>  budget_ci              18956  3
>  budget_core            12332  1 budget_ci
>  dvb_core               87948  3 stv0299,budget_ci,budget_core
>  saa7146                18080  2 budget_ci,budget_core
>  ttpci_eeprom            2520  1 budget_core
>  ir_common              43340  1 budget_ci
>  i2c_core               35280  5
> stv0299,budget_ci,budget_core,ttpci_eeprom,i2c_piix4
>  #
>
Don't remember when drivers it used, I've removed it from my box long ago.


>
> I have not yet compiled my own drivers, so I use the drivers that came
> with the disro (opensuse-11.1, x86_64).  But I am about to dive into the
> driver to narrow down the problem closer.  Any hint how to compile my
> own drivers on opensuse?

I dont have opensuse, but I'd suggest to use this repository:
http://mercurial.intuxication.org/hg/s2-liplianin


>
>
> _______________________________________________
> linux-dvb users mailing list
> For V4L/DVB development, please use instead linux-media at vger.kernel.org
> linux-dvb at linuxtv.org
> http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.linuxtv.org/pipermail/linux-dvb/attachments/20090207/abd6795f/attachment.htm 


More information about the linux-dvb mailing list