[mythtv-users] How do you "tune" subchannels in QAM?

John Sturgeon mythtv at sturgeonfamily.com
Fri Apr 1 00:38:26 UTC 2005 

Adam Gianola wrote:

>I can't figure out what is wrong because channel scanning doesn't seem
>to work at all.  At least not for me... and it sounds like others are
>also having the exact same problem.  Azap works and tunes fine and
>captures work outside of mythtv using dvbstream.  I have viewed them
>lots of times on several channels, it is fantastic to see HD captures
>from digital cable :)
>
>Mythtv, however, is not working with the hd3000-dvb & qam (or at least
>hasn't been) for me.  It seems when scanning channels in mythtvsetup,
>something is off, as the frequencies which lock are not added to the
>database in any useable way.  I only get 'timeout tuning channel' or
>'unable to tune channel' or something like this.  I thought maybe
>database entries should be added to the tables 'dvb_channel' or
>'dvb_pids' or 'channel' but the only thing i've been able to get are
>entries to 'dtv_multiplex' after scanning which help (so I may
>manually edit the db) but don't give any functionality.  I haven't
>been able to view programs yet with the above method of manually
>editing the database (away from the frontend), but i'm certainly
>stumped otherwise and am not afraid to try this.
>
>As i may have mentioned before, for me no channel information seems to
>come through with the TS which may be why myth is hanging here.  I
>think that 'dvbscan -cvvv' after azap cxxx is where i would see this
>(outside of myth) but don't.  Perhaps your cable system is providing
>this kind of information which is why you can get mythtv to autoscan. 
>Then again, maybe there's something else I'm missing...  If you can
>think of anything, I'm ready to try anything... even went so far as to
>install myth from cvs (reverted back to atrpms though), to see if
>something new was changed since the last release.
>
>Cheers,
>Adam
>
>
>
>
>On Thu, 31 Mar 2005 15:25:23 -0800, John Sturgeon
><mythtv at sturgeonfamily.com> wrote:
>  
>
>>Marc Tousignant wrote:
>>
>>    
>>
>>>I think I figured it out…
>>>
>>>Since I knew C82 program 1 was my local PBS I located the correct
>>>frequency for this channel in dtv_multiplex
>>>
>>>INSERT INTO dtv_multiplex (mplexid, sourceid, transportid, networkid,
>>>frequency, inversion, symbolrate, fec, polarity, modulation,
>>>bandwidth, lp_code_rate, transmission_mode, guard_interval, visible,
>>>constellation, hierarchy, hp_code_rate, sistandard, serviceversion,
>>>updatetimestamp) VALUES
>>>(89,1,NULL,NULL,573000000,'a',NULL,'auto',NULL,'qam_256','a','auto','a','auto',0,'auto','auto','auto','atsc',33,20050331082612);
>>>
>>>Using this knowledge I then changed the mplexid of the correct listing
>>>to 89 in channel.
>>>
>>>INSERT INTO channel (chanid, channum, freqid, sourceid, callsign,
>>>name, icon, finetune, videofilters, xmltvid, recpriority, contrast,
>>>brightness, colour, hue, tvformat, commfree, visible, outputfilters,
>>>useonairguide, mplexid, serviceid, atscsrcid) VALUES
>>>(1802,'802','802',1,'WGBHDT','WGBHDT
>>>(WGBH-DT)','none',NULL,'','28055',0,32768,32768,32768,32768,'Default',0,1,'',0,89,NULL,NULL);
>>>
>>>Starting mythbackend I then saw
>>>
>>>2005-03-31 13:55:09.792 SIParser: About to do a reset
>>>
>>>2005-03-31 13:55:09.792 SIParser: Closing all PIDs
>>>
>>>2005-03-31 13:55:09.792 SIParser: Using DelAllPids from SIParser which
>>>does nothing
>>>
>>>2005-03-31 13:55:09.792 SIParser: Resetting all Table Handlers
>>>
>>>2005-03-31 13:55:09.792 SIParser: SIParser Reset due to channel change
>>>
>>>2005-03-31 13:55:09.793 DVB#0 DVB SI Table Parser Started
>>>
>>>2005-03-31 13:55:09.793 DVB#0 Using DVB card 0, with frontend pcHDTV
>>>HD3000 HDTV.
>>>
>>>2005-03-31 13:55:09.793 DVB#0 Trying to tune to channel 802.
>>>
>>>2005-03-31 13:55:09.793 SIParser: Starting DVB Section Reader thread
>>>
>>>2005-03-31 13:55:09.793 SIParser: Starting SIScanner
>>>
>>>2005-03-31 13:55:09.794 DVB#0 Mod:
>>>
>>>2005-03-31 13:55:09.794 SIParser: About to do a reset
>>>
>>>2005-03-31 13:55:09.794 SIParser: Closing all PIDs
>>>
>>>2005-03-31 13:55:09.795 SIParser: Resetting all Table Handlers
>>>
>>>2005-03-31 13:55:09.795 SIParser: SIParser Reset due to channel change
>>>
>>>2005-03-31 13:55:09.795 DVB#0 Waiting for frontend event after tune.
>>>
>>>2005-03-31 13:55:10.055 DVB#0 DVB signal 977 | snr fde1 | ber 0 | unc 0
>>>
>>>2005-03-31 13:55:10.055 DVB#0 Status: LOCK.
>>>
>>>2005-03-31 13:55:10.055 SIParser: Requesting PAT
>>>
>>>2005-03-31 13:55:10.055 DVB#0 Multiplex Locked
>>>
>>>2005-03-31 13:55:10.055 SIParser: Adding a PMT (0) to the request list
>>>
>>>2005-03-31 13:55:10.796 SIParser: Table[0]->RequirePIDs() == true
>>>
>>>2005-03-31 13:55:10.797 SIParser: Adding PID 0 Filter 0 Mask ff Buffer
>>>40960
>>>
>>>2005-03-31 13:55:10.797 SIParser: Table[2]->RequirePIDs() == true
>>>
>>>2005-03-31 13:55:10.797 SIParser: Adding PID 1ffb Filter ff Mask 0
>>>Buffer 40960
>>>
>>>2005-03-31 13:55:10.798 SIParser: Table[3]->RequirePIDs() == true
>>>
>>>2005-03-31 13:55:10.798 SIParser: Adding PID 1ffb Filter ff Mask 0
>>>Buffer 40960
>>>
>>>2005-03-31 13:55:11.150 SIParser: PAT Version = 2
>>>
>>>2005-03-31 13:55:11.150 SIParser: Tuned to TransportID: 32950
>>>
>>>2005-03-31 13:55:11.150 SIParser: Services on this Transport: 1 2
>>>
>>>2005-03-31 13:55:11.150 SIParser: Table[0]->Complete() == true
>>>
>>>2005-03-31 13:55:11.150 SIParser: Table[1]->RequirePIDs() == true
>>>
>>>2005-03-31 13:55:11.150 SIParser: Adding PID 0 Filter 2 Mask ff Buffer
>>>40960
>>>
>>>2005-03-31 13:55:16.059 DVB#0 Timeout Getting PMT
>>>
>>>2005-03-31 13:55:16.059 DVB#0 ERROR - Tuning for channel #802 failed.
>>>
>>>Taking a guess I then went back and changed the serviceid to 1 because
>>>it was subchannel 1
>>>
>>>INSERT INTO channel (chanid, channum, freqid, sourceid, callsign,
>>>name, icon, finetune, videofilters, xmltvid, recpriority, contrast,
>>>brightness, colour, hue, tvformat, commfree, visible, outputfilters,
>>>useonairguide, mplexid, serviceid, atscsrcid) VALUES
>>>(1802,'802','802',1,'WGBHDT','WGBHDT
>>>(WGBH-DT)','none',NULL,'','28055',0,32768,32768,32768,32768,'Default',0,1,'',0,89,1,NULL);
>>>
>>>Now I am getting this in mythbackend on start
>>>
>>>2005-03-31 13:59:22.477 SIParser: About to do a reset
>>>
>>>2005-03-31 13:59:22.477 SIParser: Closing all PIDs
>>>
>>>2005-03-31 13:59:22.477 SIParser: Using DelAllPids from SIParser which
>>>does nothing
>>>
>>>2005-03-31 13:59:22.477 SIParser: Resetting all Table Handlers
>>>
>>>2005-03-31 13:59:22.477 SIParser: SIParser Reset due to channel change
>>>
>>>2005-03-31 13:59:22.478 DVB#0 DVB SI Table Parser Started
>>>
>>>2005-03-31 13:59:22.478 SIParser: Starting DVB Section Reader thread
>>>
>>>2005-03-31 13:59:22.478 DVB#0 Using DVB card 0, with frontend pcHDTV
>>>HD3000 HDTV.
>>>
>>>2005-03-31 13:59:22.478 DVB#0 Trying to tune to channel 802.
>>>
>>>2005-03-31 13:59:22.478 SIParser: Starting SIScanner
>>>
>>>2005-03-31 13:59:22.479 DVB#0 Mod:
>>>
>>>2005-03-31 13:59:22.479 SIParser: About to do a reset
>>>
>>>2005-03-31 13:59:22.480 SIParser: Closing all PIDs
>>>
>>>2005-03-31 13:59:22.480 SIParser: Resetting all Table Handlers
>>>
>>>2005-03-31 13:59:22.480 SIParser: SIParser Reset due to channel change
>>>
>>>2005-03-31 13:59:22.480 DVB#0 Waiting for frontend event after tune.
>>>
>>>2005-03-31 13:59:22.740 DVB#0 DVB signal 977 | snr fdc9 | ber 0 | unc 0
>>>
>>>2005-03-31 13:59:22.740 DVB#0 Status: LOCK.
>>>
>>>2005-03-31 13:59:22.740 SIParser: Requesting PAT
>>>
>>>2005-03-31 13:59:22.740 DVB#0 Multiplex Locked
>>>
>>>2005-03-31 13:59:22.740 SIParser: Adding a PMT (1) to the request list
>>>
>>>2005-03-31 13:59:23.481 SIParser: Table[0]->RequirePIDs() == true
>>>
>>>2005-03-31 13:59:23.481 SIParser: Adding PID 0 Filter 0 Mask ff Buffer
>>>40960
>>>
>>>2005-03-31 13:59:23.482 SIParser: Table[2]->RequirePIDs() == true
>>>
>>>2005-03-31 13:59:23.482 SIParser: Adding PID 1ffb Filter ff Mask 0
>>>Buffer 40960
>>>
>>>2005-03-31 13:59:23.483 SIParser: Table[3]->RequirePIDs() == true
>>>
>>>2005-03-31 13:59:23.483 SIParser: Adding PID 1ffb Filter ff Mask 0
>>>Buffer 40960
>>>
>>>2005-03-31 13:59:23.899 SIParser: PAT Version = 2
>>>
>>>2005-03-31 13:59:23.900 SIParser: Tuned to TransportID: 32950
>>>
>>>2005-03-31 13:59:23.900 SIParser: Services on this Transport: 1 2
>>>
>>>2005-03-31 13:59:23.900 SIParser: Table[0]->Complete() == true
>>>
>>>2005-03-31 13:59:23.900 SIParser: Table[1]->RequirePIDs() == true
>>>
>>>2005-03-31 13:59:23.900 SIParser: Adding PID 30 Filter 2 Mask ff
>>>Buffer 40960
>>>
>>>2005-03-31 13:59:24.121 SIParser: PMT ServiceID: 1 Version = 4
>>>
>>>2005-03-31 13:59:24.121 SIParser: PID: 2048
>>>
>>>2005-03-31 13:59:24.121 SIParser: Unknown descriptor, tag = 6
>>>
>>>2005-03-31 13:59:24.121 SIParser: Unknown descriptor, tag = 134
>>>
>>>2005-03-31 13:59:24.121 SIParser: PID: 2049
>>>
>>>2005-03-31 13:59:24.121 SIParser: Unknown descriptor, tag = 129
>>>
>>>2005-03-31 13:59:24.122 SIParser: PID: 2050
>>>
>>>2005-03-31 13:59:24.122 SIParser: Unknown descriptor, tag = 129
>>>
>>>2005-03-31 13:59:24.122 SIParser: Table[1]->EmitRequired() == true
>>>
>>>2005-03-31 13:59:24.122 DVB#0 Successfully tuned to channel 802.
>>>
>>>I am not sure if this is really working as I am not at home to try it.
>>>Was playing with it during my lunch break and wont be able to try till
>>>I get home.
>>>
>>>My hopes are high that I am on the right track thou.
>>>
>>>      
>>>
>>>>I think quite a few of us working with the hd3000 are having the same
>>>>        
>>>>
>>>>problem and are looking for solutions. I've posted both here and in
>>>>        
>>>>
>>>>the hd3000 forum but it seems like no one has been able to find a
>>>>        
>>>>
>>>>solution to this problem yet. I haven't posted to myth-dev yet, but
>>>>        
>>>>
>>>>maybe thats the place where we may find someone who knows the answer
>>>>        
>>>>
>>>>to our question, as i think it is a problem with how mythtvsetup is
>>>>        
>>>>
>>>>handling the hd3000-dvb. For example, when i run dvbscan -cvvv no
>>>>        
>>>>
>>>>channel information is given, but i've seen examples with OTA ATSC
>>>>        
>>>>
>>>>streams where channel information is explicitly supplied in the
>>>>        
>>>>
>>>>stream. Mythtv may be looking for this and since it doesn't come
>>>>        
>>>>
>>>>through, myth assumes the channels are 'unable to tune'.
>>>>        
>>>>
>>>>-Adam
>>>>        
>>>>
>>>>for reference:
>>>>        
>>>>
>>>>http://www.xmission.com/~pchdtv/forum/viewtopic.php?t=639
>>>>        
>>>>
>>>>http://www.xmission.com/~pchdtv/forum/viewtopic.php?t=634
>>>>        
>>>>
>>>>http://www.gossamer-threads.com/lists/mythtv/users/121772
>>>>        
>>>>
>>>>http://www.gossamer-threads.com/lists/mythtv/users/120911
>>>>        
>>>>
>>>>http://www.linuxtv.org/wiki/index.php/PcHDTV
>>>>        
>>>>
>>>------------------------------------------------------------------------
>>>
>>>_______________________________________________
>>>mythtv-users mailing list
>>>mythtv-users at mythtv.org
>>>http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>>>
>>>
>>>      
>>>
>>AACK!
>>
>>You shouldn't have to do this! Please make sure your card is configured
>>correctly.. (see my previous post) Channel scanning should work just
>>fine, and put all of the appropriate entries in your channels lineup. If
>>it doesn't, something else is probably wrong.
>>
>>--
>>John Sturgeon <><
>>http://www.sturgeonfamily.com/mythtv.php
>>
>>    
>>
The missing piece for me was the QAM part.  I'm not sure if that makes a 
substantial difference, but that may be it.  Perhaps other HD-3000 QAM 
folks can answer.

Good Luck!
-- 
John Sturgeon <><
http://www.sturgeonfamily.com/mythtv.php

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