[mythtv] Ramblings on the 128 Channels and Satellite

tarek Lubani mythtv-dev@snowman.net
Thu, 24 Oct 2002 06:12:09 -0400 (EDT)


Well, I have spent the better part of the night trying to figure this 
puppy out.. to no avail..

The problem: 

a) I have a satellite hooked into my composite1
b) Said satellite (DirecTV) goes from 100 - 999.
c) Myth won't let me go beyond ~125 channels.. i.e., I can't type in more 
than "125". If I do, it just spits back the original channel I was on.

I've been going through the code, but being a novice programmer and not 
knowing this program well at all, I was completely unsuccessful... Here's 
what I have found, though:

1) This was reported as a database issue some time ago.. I don't exactly 
know why.. but it was : )

2) Isaac Richards stated in an email back in august 2002 that there was a 
hard-coded 128 channel limit. This boggles my mind for several reasons. 
Which isn't to say much, since I truly don't know much in this area.. but 
why can't hitting "500" just bring up the OSD? isn't this what currently 
happens? or is my tv tuner actually switching channels??

I really had trouble finding the 128 "line", since god knows 128 is common 
enough in code : ) However, in the end, I found a line of this variety in 
guidegrid.h in /usr/libs/libmyth .. Surely enough, this was set to 128.. 
So, I changed it to 999 and recompiled.. nothing. Still the same 
behaviour. still the same problems.. In fact, I cannot at all figure out 
what this setting does when a person is trying to change channels in 
composite mode..

Anyway, suffice it to say that after breaking a whole bunch of things in a 
whole bunch of files around, I just had to mothball the effort and 
regroup.. So, I'm seeking more advice here..

Questions I currently have:

1) If I hit 500, what does myth do?

2) What is an approximate vicinity of the code where I should be looking?

3) Why is this a problem? Why can't I just hit "500", have it execute a 
500 external command, and then we just be done with it.. Why does it do 
this internal dissonance checking? And more importantly (as relating to 
question 2), where does said checking occur??

Thank you all for your help..

tarek : )