[mythtv-users] Re: myth doc contrib

[Joseph A. Caputo]

Comments inline.

On Sunday 30 May 2004 02:01, Joe Byrne wrote:
> The following is based on the mythtv-users mailing list message from
> jcaputo1 at comcast.net of 9 Dec 2003
> (http://www.gossamer-threads.com/lists/mythtv/users/44731#44731) and
> should be filed under Misc.  Could people more knowledgeable than I
> validate this contribution so that it can be added to the docs?
>
> How do I enable the use of an auxiliary input on a tuner card?
>
> It is possible to hook a VCR or security camera up to a free
> composite or SVideo input port of  a tuner card, assign a channel
> number to the port, and record (via manual scheduling) or view (via
> live TV) the input to said port.
>
> The first step is to create a new video source for the input port. 
> Run mythtvsetup.  Answer no to the initial questions.  Select the
> "video sources" menu option and create a new video source.  Call it
> Aux1, for example.  Select tv_grab_na as the listings grabber (if a
> null option were available, that would be a better selection); leave
> the zip code field blank.  Select Finish.  Ignore the subsequent
> error.  This setting will be manually set to null in a subsequent
> step.

Just a note; tv_grab_na has now been removed as a choice, as it is not 
being supported by XMLTV any more.

> The second step is to assign the source to the free port.  Go to the
> "input connections" section of mythtvsetup and bind the newly created
> video source (Aux1) to the appropriate input port.  Some trial an
> error may be required to select the port that corresponds to the
> actual physical port on the card.
>
> The third step is to associate the port with a channel.  Go to the
> "channel editor" section of mythtvsetup and create a new channel.  To
> minimize confusion, choose a channel number that doesn't coincide
> with available channels on other sources.  A number above the highest
> one from the other sources is convenient.  When this step is
> complete, exit mythtvsetup.  Do NOT run mythfilldatabase.

I would actually swap the order of steps 2 & 3.  The reason is that when 
you bind the video source to an input, you need to give it a starting 
channel and a default channel.  You'll need the channel number that you 
create to fill in these values.

I don't know if it's OK to leave the 'pre-tune to channel' blank, but I 
do know that if that field contains a channel that does not exist in 
the video source, it's problematic.  My experience was that, in 
configuring a video source on my S-Video input, I got the correct video 
but the audio was left on Tuner0.  Took me a while to track that one 
down; the best solution is to make sure you pre-tune to the correct 
channel.

> The fourth step is to make sure that mythfilldatabase does not try to
> grab listing info for the bogus channel just created.  This requires
> editing the database and setting the listings grabber to null, since
> (as of 0.15) null is not an option.  This can be done with sql
> commands.

Maybe give an example of a correct SQL command here?  Like:

shell%: mysql -u mythtv -pmythtv mythconverg

mysql> SELECT sourceid, name FROM videosource ;
mysql> UPDATE videosource SET xmltvgrabber = NULL WHERE sourceid = [id 
from previous query] ;

>
> Alternatively, install phpMyAdmin and let your mouse do the walking. 
> The latter is easy if MythWeb is installed.  Untar/zip phpMyAdmin to
> Apache's document root (e.g. /var/www/html).  Configure it per its
> documentation.  Go to http://yourbackend/yourphpMyAdmin.  Select the
> mythconverg database in the left-hand frame.  The page redraws. 
> Select videosource in the left-hand frame.  Click browse at the top
> of the right-hand frame.  Click the edit icon for the source just
> created (Aux1).  Set the NULL check box for xmltvgrabber.  Click go.
>
> Done.
>
> At this point, running mythfilldatabase will not try to grab listings
> for the bogus channel.  However, it will show up in the EPG.

Nice work!

-JAC