zen.org Communal Weblog

About a week ago we were able to display live TV thru the box, but the remote didn’t work and we couldn’t move through channels. It’s much happier now. Problems that still need to be fixed:

• Sound for non-AVI video files is out of sync
• The X display is bigger than the TV screen
• I have to switch the audio output between the Shuttle’s L/R audio out for video files and the audio out of the PVR-350 for live and recorded TV.
• I need a way to make MythTV be able to change channels on the NTL Pace 4001NC box, which reportedly uses RC-5 protocol for the remote. Given that, we can also record everything coming from NTL Digital Cable. There is one cool serial hack that on its main page seems to clearly indicate it will work with my box, which after some clarification is confirmed to work with it. So we’re ordering one now and will share the results once we’ve got it.
• Sometimes after a reboot the live TV doesn’t work for more than a few seconds, and more notably the name of the tuner and the current time don’t appear at the top of the screen. After only a minute or two, it goes back to the menu. If I restart mythbackend, it’s then all happy and can keep going.
• The PVR-350 can accept the FM antenna; can MythTV record radio shows too into mp3 format? A google for “MythRadio” has a few hits for recent conversation. But anything I’d try for this has to wait til everything else works. 🙂

What we’ve got now is pretty usable for day-to-day stuff, with the one physical hurdle of having to use an audio switch box to change which of the two audio sources actually gets emitted. There must be a system/MythTV fix, or we could just get some sort of an RCA jack Y-joiner/junction thing to accept output from either one…Hmm….

Some details on how we got it working:

1. The remote problem was because /etc/lircd.conf defines particular names for each button like

   
CH+ 0X00000000000017E0
CH- 0X00000000000017E1
VOL+ 0X00000000000017D0


   The entries in ~/.mythtv/lircrc need to match those names in some fashion. I just had to change
   
begin
prog = mythtv
button = chanup
repeat = 5
config = Up
end

   to instead have
   
begin
prog = mythtv
button = CH+
repeat = 5
config = Up
end


   This helped improve watching live TV or shows recorded by the box. But we were stuck when watching a video file like an MPG (which has its own problems anyway) or AVI file; you couldn’t get it to return to the menu after starting to watch it.

2. I came across Adam Rubin’s description of how he made the remote more usable with MythTV. So I just needed to give ~/.mythtv/lircrc a few entries like
   
begin
remote = hauppauge_pvr
button = Pause
prog = mplayer
repeat = 3
config = Pause
end

   to help improve things.
3. The file ~/.mythtv/NTL Basic Cable.xmltv contains the final list of channels I’m using. It omits the pay channels.
4. I had to make /etc/rc.d/rc.local do modprobe ivtv so the driver, and its ivtv_fb framebuffer driver, are all loaded up before anything else. I also added the lines
   
/usr/X11R6/bin/xset -dpms
/usr/X11R6/bin/xset s off

   to make it stop having a blank screen until I hit a key on the (tucked away) keyboard.
5. My final /etc/X11/xorg.conf file makes everything show up on the TV from the PVR-350’s S-Video feed, but the X display is still just slightly larger than the TV screen. When I’m going through the MythTV setup menus it’s impossible to see the selection boxes along the left side.
6. Playing AVI files using the default mplayer now works by giving it the options
   -ao oss -vo x11 -nocache
   However, playing MPG files doesn’t work quite as well. I found others talking about this and how audio seems to come out directly via the sound port, but the video is going through the MPG decoder first. I did find some bits in the MythTV Digital Sound HOWTO and put them into my ~/.asoundrc. But I’ve not spent enough time looking at it to remember how to make MythTV use that, as opposed to the default /dev/dsp device.

So far so good; much more productive than the efforts with KnoppMyth, seemingly just because the version of the mythtv stuff is much more up-to-date.