[mythtv-users] Multiple tuners, multiple sources...

Bruce Markey bjm at lvcm.com
Fri Mar 12 07:45:14 EST 2004

Scott Nicholson wrote:
>>>I want to connect the digital cable receiver to one of the tuners.
>>>I'd like to be able to connect both the USDTV (on S-video) AND my
>>>cable (on coax) to the second tuner -- so that analog cable channels
>>>are available.
>>Man, what a complex situation!  Just for clarification, you'd have 3
>>Analog cable
>>Digital cable
>>with the following connections:
>>Digital cable 	-> SVideo0 or Composite0
>>Analog cable	-> Tuner1
>>USDTV		-> SVideo1
> Correct.
>>(and just to make things more complex, you could split your cable and
>>also hook up Analog Cable -> Tuner0, but we'll ignore that for now)
> True... Hadn't thought of that.
> Just to clarify... Myth does treat each input on each capture card as a
> different source, right? (Obviously I can't record on both the SVideo and
> the Tuner on the same card at the same time).

More clarifying ;-). 

Source = provider for TV listings (CoxCable, CoxDigital)
Input = connector (coax, s-video)
Card = thing that cuts your fingers when you shove it in the slot.

You can use multiple inputs on a card and the scheduler knows
that can only record one thing at a time on a card. You can use
the same source for different inputs on different cards (or even
the same card) and the scheduler knows that it can record a show
from that source on any of those inputs. And you can have multiple

>>The good news is that, although having a channel duplicated in multiple
>>sources used to be a nightmare, CVS has (IIRC) the ability to correlate
>>channels in different sources, if they have the same callsign.  This
>>means that, across all 3 sources, a channel with the callsign 'FOODTV'
>>is considered the same channel.  However, 'FOODTV-HD' would be a
>>different channel.  I'm not sure if that heuristic applies to the
>>scheduler or just the EPG view... if it doesn't affect the scheduler,
>>then you're out of luck.
> It sounds like even if the scheduler isn't affected things are at least
> moving in that direction?

Joseph is essentially correct but there has been a big move in
this direction that's pretty new so let me give it a shot =).

When 0.15 is released or in CVS now, the scheduler has two new
features for matching stations based on callsign and a feature
for adding priority preference values for inputs (ex. s-video
on card 2 can be given a higher value than coax on card 1) Using
both of these will allow you (and the scheduler) to do nifty

If two or more things in the channel table have the same "callsign"
the scheduler will consider these to be the same broadcast station
with the same listing (you have to make sure that is true ;-).
These can be the same or different channel numbers on the same or
different source. As long as the callsign is the same it assumes
it has the same listings. The EPG was also hacXXX improved to
show just one of these channels rather than repeating the listings.
When you choose a show from that broadcast station, say FOOD, it
knows that it could record that show from any Source->Card->Input
that has "FOOD".

I'll guess wrong and say you have FOOD on HDTV channel 124 from
the card 2 svideo and FOOD on channel 44 for the analog and digital
inputs. You have three different sources with FOOD available on
four different inputs. So which will be chosen for "Iron Chef"?

In the backend "setup" program, you can go to Input Connections
and choose the input for HDTV on card 2 s-video. Change the Input
preference to "1". The scheduler adds this to the priority when
it's prioritizing. The result is that if Iron Chef has a priority
of 5, it will have priority 6 for the HDTV and 5 for all the others.

This means that it will alway try to record Iron Chef in HD.
However, if some other show with a higher priority already gets
the HDTV input, the scheduler will try to use one of the other
S/C/Is to record Iron Chef.

>>Unfortunately, I don't think Myth currently has the capability to
>>indicate card preferences.
> Any idea if this is something that may be added in the future? (Has it been
> requested before / is it something the devs would be interested in
> implementing?)

It is not in the current 0.14 release but will be in 0.15 and
has been in CVS for about two weeks.

>>(3) name the channels as in (2) above, but set up two identical
>>recordings -- one for "FOODTV" and one for "FOODTV-HD".  Give the one
>>on "FOODTV-HD" a higher priority.  Worst case, it records twice.  Best
>>case (if you turn on duplicate detection & you have enough program
>>information), the lower priority one will be suppressed because the
>>scheduler knows it's being recorded elsewhere.  Hey, it ain't pretty,
>>but it might work...

You would only want to add "-HD" if there were differences in
the schedules. Otherwise, use the same callsign and the the
Input preference will take care of the preferred input and can
fail-over to another input when necessary.

--  bjm

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