[mythtv] Fwd: [linux-dvb] USB DVB-T tuners and MythTV

Daniel Kristjansson danielk at cuymedia.net
Tue Oct 11 18:55:14 UTC 2005

On Tue, 2005-10-11 at 19:26 +0100, Jim wrote:

> using svn 7448 I find that if you comment out the following 4 lines in 
>   DTVSignalMonitor::IsAllGood then everything (liveTV/Recording) works
>   with the same speed improvements to channel change etc
> if ((flags & kDTVSigMon_WaitForPAT) && !matchingPAT.IsGood())
>             return false;
> if ((flags & kDTVSigMon_WaitForPMT) && !matchingPMT.IsGood())
>             return false;
This would tend to indicate that the PAT and PMT check failed.
You might want to print out the PAT table in DTVSignalMonitor::SetPAT()
by adding a "VERBOSE(VB_IMPORTANT, "PAT is: \n" << pat->toString());"
And the same for the PMT.

If these never print anything out, you might want to try running
the backend at "-v record" and looking for any "PSIP packet failed
CRC check" messages. It is possible that the device is changing
these and not setting/calculating the packet CRC properly. There
is a function in videosource.cpp called HasDVBCRCBug() you can
try patching this to return true for your device.

> Two minor points I noticed in rummaging around:
> a) There appears to be a typo in DTVSignalMonitor::IsAllGood in that the 
> MGT test is repeated in the VCT line: 

> b) The fix for embedded quotes in the DVB channel name hasn't quite done 
> the job - I understand why a bind variable would be better but don't know 
> how to do this in mysql - the following does work however. (svn 7449)
I'll look at this.

-- Daniel

More information about the mythtv-dev mailing list