[mythtv-users] minimize possibility input/capture card will be used for live TV

[Michael T. Dean]

On 03/14/2017 04:30 AM, Stephen Worthington wrote:
> On Mon, 13 Mar 2017 22:43:10 -0500 (CDT), you wrote:
>
>> 0.27 MythTV system installed under gentoo. 3 capture cards, all USB. 2
>> cards devoted to bringing in OTA, 1 hooked to the cable company DTA's "TV
>> out" coaxial jack for recording SD. The last-mentioned card sees the most
>> use since it is set to record a program each weekday.
>>
>> The problem with this set-up is that, whenever I go to watch live TV, the
>> system seems always to want to use the capture card hooked to the DTA
...
>> Looking around today I found
>> https://www.mythtv.org/wiki/Setup_Input_Connections, which seemed like it
>> might provide a solution. There it says, under "live TV order," "When
>> entering Live TV, the available, local input with the lowest, non-zero
>> value will be used." So I thought I would just need to assign the
>> input/capture card in question a higher value. But when I began
>> investigating, I discovered that it already had the highest value: its
>> value is set to 25, while the other OTA cards have values 18 and 14. So
>> the system should be, from what I'm gathering, using one of those 2 inputs
>> before it tries to use the one enumerated as 25. But that's not the
>> behavior I'm seeing.
...
> When you go into LiveTV from the "Watch TV" menu, it tunes to the last
> channel LiveTV was tuned to.  If that channel was one that is only
> available from the DTA, then it will use the tuner connected to the
> DTA.

Exactly.

>    If you then change to a channel that is only available via the
> OTA tuners, it will switch automatically to the one of them that is
> set to the lowest Live TV Order value and is not already in use.
> However, if you change to a channel that is available on both the OTA
> tuners and the DTA, I am not sure what the behaviour is - it may
> switch to the OTA tuners, but it may stay on the DTA tuner.

It will stay on the current input.  It only switches inputs when 
required--or when explicitly told to (using NEXTSOURCE, NEXTINPUT or 
NEXTCARD).  https://www.mythtv.org/wiki/Keybindings#Watching_TV_only , 
which references Y , which is the default for NEXTSOURCE.  You may need 
to use NEXTINPUT (C) or NEXTCARD (no default key--you can bind it under 
Utilities/Setup|Key Bindings)

>    If in
> that situation you wanted to make sure it switched to an OTA tuner,
> you would need to ensure that all channels that are available on both
> the OTA and DTA tuners had lower channel priorities on the DTA tuner.
> Or you could give the DTA tuner a lower priority than the OTA tuners,
> so that the OTA tuners will always be tried first.

Priority--both input and channel--only affects recordings, not Live TV 
channel selection.  Live TV is "interactive" TV--meaning that it does 
exactly what the user tells it to do and only what the user tells it to 
do--no priority or Live TV order will cause it to switch inputs if it's 
using an input that works.

So, if you want to make sure it switches to an OTA tuner, you need to 
tell it to go directly to a channel that's only available on the OTA 
tuner.  "But all the OTA channels are available on my DTA," you say?  
So, change that.

How do you tell Live TV to go to a channel?  There are 2 different 
ways:  you either select a channel from browse mode/guide or you type in 
a channel number.  If you've configured your channels such that all the 
"equivalent" channels on the OTA and DTA sources have the same call sign 
(basically a short channel "uniqueness" identifier used for MythTV 
recordings) and channel number (basically the "go directly to this 
channel in Live TV" identifier for MythTV Live TV), MythTV treats the 
channels--even though they're on different Video Sources--as exactly 
identical and, therefore, condenses listings to only show one copy of 
that channel information.  That means you cannot choose which channel to 
watch in Live TV (because you've told MythTV they're exactly 
identical)--information about it only shows once in browse mode/guide 
and the channel number is the same.  So, if you want to be able to 
choose which one to tune in Live TV, simply change the channel number of 
one version or the other.  So, for example, if you have channel 9_1 on 
both your OTA and DTA Video Sources, change the channel number of one of 
them (I'd recommend the DTA one--since that's not the one you want to 
tune in Live TV) to, say, 1009_1. Then, in Live TV, you can type 9_1 to 
go to the OTA channel and 1009_1 to go to the DTA channel, or you can 
select 9_1 or 1009_1 in browse mode/guide--they're actually shown 
separately.  Note that the channel number need not have any relation to 
the channel number used by your provider (OTA or cable/satellite 
provider)--the frequency identifier is the one that has to reflect the 
provider's layout but channel number is a user-specified "quick change" 
identifier for Live TV channels.

If you keep the call signs the same, then MythTV will still record from 
either of them for normal (non-Live-TV) recordings using the "this 
channel" filter (choosing which input based on channel or input 
priority--note, though, that you probably don't want to change input 
priority because it can cause you to miss recordings because you said, 
"the show isn't good enough if you can only record it from the 
less-preferred input").  That said, generally you should be using 
any-channel rules (i.e. rules without the "this channel" filter), so 
even call sign would be irrelevant.

> If you want to start watching on an OTA channel, and LiveTV was last
> on a DTA channel, you can do that by going to the Guide and using M
> (menu) from the channel you want and selecting "Watch This Channel".

Right.

Mike