[linux-dvb] Re: DVB, MythTV and PVR-350

[Jan <linux-dvb@jan-doelle.de>]

Am Dienstag, 21. Dezember 2004 22:12 schrieb Hamish Moffatt:
> On Tue, Dec 21, 2004 at 10:38:12AM -0800, Florin Andrei wrote:
> > On Tue, 2004-12-21 at 15:17 +0100, Jan wrote:
> > > Am Montag, 20. Dezember 2004 08:21 schrieb Florin Andrei:
> > > > Anyone here using a DVB card in conjunction with MythTV and a PVR-350?
> > 
> > > I am using a AverTV DVB-T 771 Card beside my PVR-350. I have a lot of trouble 
> > > with the bt878 driver if both card running (recording). 
> > > ...
> > > Nov  7 14:17:16 localhost kernel: bt878(0): irq FBUS risc_pc=1e41a210
> > > 
> > > The result is a heavy damaged mpeg stream.
> > 
> > Wow, that's pretty bad.
> > 
> > If you take the DVB card off-line, then it's fine, right?
> > Sounds like a driver issue to me...
> 
> IMHO it's due to the FIFO in the BT878 being too small for DVB data.
> It's designed for audio but it's being run at up to 10x the data rate
> to carry the MPEG2 transport stream. (Possibly more like 15x.)
> 
> The FIFO overflows because the card had to wait too long to get access
> to the PCI bus. You may be able to improve the situation by fiddling
> with the PCI latency timers (man setpci); probably by reducing the
> counters on your OTHER cards, rather than doing anything for the A771 in
> particular.

Oh yes, nice fiddling,  I tried .... :-p

> 
> I have two DVB cards (one BT878, one not) and see this very
> occasionally. No amount of latency tweaking has gotten rid of it
> completely.
> 
> Hamish

Hamish, thank you again, 
finially you give me the best idea to solve my A771 Issue: eBay!

Did anyone know a linux working (no patching hell) dvb-t card with - please - not a bt878 chipset? 
Ok, and it must also have perfect qualitiy, big buffers (big sounds good) and of cause is very cheap  ;-)

Chees Jan