[mythtv-users] Rigging Channel Lineup

R. G. Newbury newbury at mandamus.org
Sat Aug 11 01:49:41 UTC 2007

Michael T. Dean wrote:
> Channum is yours to change as you like--you can make it any number you
> want (i.e. when your stupid cable company puts Fox 35 on channel 3, you
> can give it channel number 35, like it was meant to have).  The only
> real "requirement" is that each different channel has a different
> channel number.
> The only purpose of a channel number is to allow you to specify which
> channel to watch during LiveTV.  (That's why different channels should
> have different channel numbers--so when you type in 35, you go to the
> channel you want.  If you have multiple different channels with the same
> number, and you type in that number, you'll go to the "first" one with
> that number.  Then, once you're on that channel, typing in the channel
> number again will do nothing (Myth knows its already on that channel, so
> it doesn't change the channel).
> Frequency ID tells Myth what frequency to tune for a particular
> channel.  Values less than 10000 are considered channel numbers (though
> values that don't exist in the specified frequency table will cause
> errors).  Values greater than 10K are considered frequency in kHz.  So
> this is the only one you have to change so that Myth will tune the
> appropriate channel when it records.  (In the US, you should never
> specify frequencies as all US frequency tables have already been defined
> in Myth.)

But channum is not used to order the channel listing in the EPG.

I have a mix of analog cable and OTA digital channels. The OTA channels 
show up in order of the actual channel frequency and changing channum 
(from 7.1 to 107.1) does not change the order.
I understood that digital channels do not use the freqid, but instead 
use the tuning information referenced through mplexid into the dtv 
_multiplex table. But that seems to make atsc_major_chan, and 
atsc_minor_chan redundant along with freqid.
Clearly, analog channels need only the freqid. But do digital channels 
use that field at all? Can I arbitrarily change that field?

I tried to read the code, but got lost. Very quickly I might add. I was 
unable to even find where the mysql select statement for the EPG is...


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