Just a stab in the dark but could it be a permissions error on the file /dev/video0 ? I've had some weird things happen where I didn't have the correct permissions trying to open the video from Mythbuntu 8.10. I tried the shotgun approach and did a chmod on the video0 with 777 to allow everything access just to test. This worked for me.
On Tue, Jan 6, 2009 at 3:09 PM, fivenote <[email protected]> wrote: > Great tips. Here's what I found... > > I disabled mythtvbackend and used sysfs interface to control the > driver. I also confirmed it is creating /dev/video0. > > The enum_val shows all 4 inputs (dtv, television, composite, svideo). > For fun I restarted mythbackend and mythtv and watched enum_val narrow > successfully between dtv and television. DTV signal came through, but > still no television signal came through. > > I disabled mythtvbackend again and checked sysfs. All four inputs > showed, meaning nothing was left open and narrowed. > > I switched cur_val to 'composite' and hooked up a video player to the > HVR-1950's composite input. mplayer still didn't work. I tried xine > and it says "There is no demuxer plugin available to handle > '/dev/video0'. I'll try to figure out what that is. Any hints are > welcome. > > Meanwhile... fyi... When I installed v4l drivers, it had it's own > pvrusb source and replaced the one I downloaded from Mike's site. Is > there a difference between the pvrusb2 source at Mike's site and > LinuxTV? Which is more current. I figure this is worth mentioning so > we know what source I'm running. > > Thanks for all your help. I'm learning more each time and hope to > figure it out soon. > > On Tue, Jan 6, 2009 at 2:18 AM, Mike Isely <[email protected]> wrote: > > > > Vincent: > > > > Additional comments and ideas are laid out below... > > > > On Mon, 5 Jan 2009, fivenote wrote: > > > >> Thanks. > >> > >> I tried running /usr/bin/mythtv-setup.real -v all. Got lots of output > >> but no obvios problems. > >> > >> I went back to basics and tried to get data from the device. I > >> shutdown mythbackend and did... > >> > >> >cat /dev/video0 > >> cat: /dev/video0: Input/output error > > > > I'm assuming that /dev/video0 is your device - do an "ls -l /dev/video*" > > and make sure you get back what you expect, e.g. if there are multiple > > entries make sure you are talking to the right one. And there *can* be > > multiple entries even for a single device if you unplugged the device > > from the USB spigot while someone was operating it. In that case, the > > old /dev/video0 can't go away until the entity hanging onto the open > > device handle has exited (perhaps some piece of mythtv is still not > > letting go). Then when you plug it back in, the "new" instance will > > become /dev/video1 because /dev/video0 is still allocated to something > > else (i.e. the previous dying driver instance due to the previous unplug > > event). > > > > But assuming that /dev/video0 is correct... > > > > EIO ("Input/output error") will happen if the stream can't be started. > > This is NOT what happens if you can't receive any video. In that case > > the stream will start but you won't receive any data (it will just > > stall) or you'll receive noise for video (depending on the situation). > > The fact that you got an EIO strongly suggests that streaming failed > > because something else already has the device open. And that something > > else doesn't have to be someone with /dev/video0 open - it might be a > > process operating the DVB side of the device. The HVR-1950 hardware is > > shared between V4L and DVB so if one side is trying to stream (even if > > only to acquire a signal lock in the case of DVB) then the other side is > > kept out of the way. You said you shut down the mythtv back end, but it > > sure sounds like that didn't entirely work. I'll bet you've got > > something hanging onto the DVB side. > > > > Try cat'ing /sys/class/pvrusb2/*/ctl_input/enum_val and see what input > > choices are in the list. If you're only seeing "dtv" that means the > > input selection has been narrowed because the DVB interface is active - > > somebody is accessing it. That would explain the behavior you are > > seeing. To understand what I mean about "narrowing", go here: > > > > http://www.isely.net/pvrusb2/usage.html#Interactions > > > > and then scroll down to the section titled "V4L vs DVB interactions". > > > > > >> > >> and... > >> > >> > mplayer /dev/video0 > >> MPlayer 1.0rc2-4.3.2 (C) 2000-2007 MPlayer Team > >> CPU: Intel(R) Core(TM)2 Duo CPU T5450 @ 1.66GHz (Family: 6, > >> Model: 15, Stepping: 13) > >> CPUflags: MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1 > >> Compiled with runtime CPU detection. > >> > >> Playing /dev/video0. > >> Win32 LoadLibrary failed to load: avisynth.dll, > >> /usr/lib/win32/avisynth.dll, /usr/local/lib/win32/avisynth.dll > >> > >> > >> Exiting... (End of file) > >> ------- > >> > >> Both of these used to work before I updated to the latest v4l drivers. > >> I don't know what else to try. > >> > > > > However we really need here to separate questions of what is going on in > > MythTV versus what is going on in the driver. You are raising issues > > and we can't tell who is causing what. I think given the confusion you > > are experiencing that you should unambiguously kick the applications out > > of the way and focus your attention purely on the driver. Only then, > > after we know the driver is healthy, should you bring MythTV back into > > the puzzle. So do this: > > > > 1. Disable the mythtv backend from even starting (i.e. rename the binary > > so that a system boot script can't start it without your knowledge). > > > > 2. Unplug the HVR-1950 from the USB port. > > > > 3. Reboot your system. > > > > 4. Plug in the HVR-1950. > > > > The idea for the above is not so much to reset the hardware but to start > > up in a way that gives high confidence that nobody is trying to access > > the device "behind your back". Everything should come up clean and > > nobody should be trying to use the device, DVB or V4L. > > > > Now run through some of the usual tests with the V4L side. Try mplayer > > while using the syfs interface to control the input selection and tuning > > frequency (again, see the above page for information about those > > interfaces). If after that you are still having analog tuning problems, > > peel back another layer: plug a composite video source into the device > > (VCR, DVD player, camcorder, etc) and try to stream from that input. > > An operation like that does not require a working RF tuner. If that > > works, then we know at least everything except the RF tuner is ok. Do > > all that first and you can verify that you have working analog hardware. > > > > Then try a simple DVB application for the DVB side. Verify that works. > > > > If you get past those steps then you've confirmed that the hardware is > > healthy and the pvrusb2 driver and all the various related V4L & DVB > > software bits are all working correctly. Then turn your attention back > > to MythTV and debug that... > > > > -Mike > > > > -- > > > > Mike Isely > > isely @ pobox (dot) com > > PGP: 03 54 43 4D 75 E5 CC 92 71 16 01 E2 B5 F5 C1 E8 > > _______________________________________________ > > pvrusb2 mailing list > > [email protected] > > http://www.isely.net/cgi-bin/mailman/listinfo/pvrusb2 > > > > > > -- > ~~~~~~~~~~~~~~~~~~~~ > VAO - [email protected] > ~~~~~~~~~~~~~~~~~~~~ > _______________________________________________ > pvrusb2 mailing list > [email protected] > http://www.isely.net/cgi-bin/mailman/listinfo/pvrusb2 > -- [email protected] Eddie Izzard - "I grew up in Europe, where the history comes from." _______________________________________________ pvrusb2 mailing list [email protected] http://www.isely.net/cgi-bin/mailman/listinfo/pvrusb2
