Andy - thanks for the excellent speculation! Follow-up: Frustration got the best of me after being unable to obtain any useful debug output from the tveeprom and cx18 drivers. I reinstalled, going from ubuntu 10.10 proper to mythbuntu 10.10. Upon reinstall, symptoms went from every channel locking in the mythtv scanner to no channels locking. On a lark, I switched to the nouveau X driver from the proprietary nvidia driver (the stock nv driver didn't seem to like the HDMI output on my card). Upon doing so, I was finally able to obtain expected output from the analog portion of the card and the mythtv channel scan completed successfully.
I'd be curious to know if a switch to the nouveau driver rectifies this issue for anyone else. thanks, josh restivo On Sat, Dec 4, 2010 at 2:04 PM, Andy Walls <[email protected]> wrote: > On Fri, 2010-12-03 at 20:47 -0800, joshr wrote: >> AMD64, 2.6.35-23 (ubuntu), hvr1600 w/ TCL M30WTP-4N-E tuner >> >> OTA Digital works great out-of the-box. Analog has been a pita though. I've >> tried forcing the tuner to a known working channel and dumped the mpeg >> stream to a file for review. Everything turns up with a blank red screen. >> Tried setting vmalloc=256M just for fun (it didn't seem to be a necessity) >> but same results. Using mythtv's channel scanner, every single channel >> scanned locks and is added to the database. Not even the channels that >> should be working show up in LiveTV, though - just blank red screen. There >> is no cable box involved here and the cable works just fine otherwise. > >> Thoughts? Suggestions? Wild speculation? > > This has been reported before, but there is no known solution. > > <speculation type=mild> > Either the CX23418's intergrated '843 Audio/Video decoder isn't > converting the analog signals into video and audio properly, or the > video data isn't successfuly getting written into the DDR RAM on the > HVR-1600. > </speculation> > > <speculation type=wild> > The root cause may be: > > - some PCI bus errors during driver load that messes up the setup of the > CX23418's A/V decoder or RAM controller. > > - you have a marginal or defective HVR-1600 or something about your > systems' PCI bus or power is marginal. > > - some kernel bug somewhere trashing the the CX23418 register space. > </speculation> > > > If the problem is reliably reproducable you could: > > 1. Try the HVR-1600 in a Windows box to see if it is defective > > 2. Try the HVR-1600 under Windows on the problem machine > > 3. Remove all uneeded PCI cards and USB devices, and see if it works > when there is less power draw by peripherials. > > 4. ensure you're not using the closed source drivers with your kernel. > The CX23418 register space is 32 MB, That's a big target in kernel > space for a kernel or driver bug to hit with an errant stray write. > > Those are just suggestions. None are guaranteed to be sane or make > anything better. > > You can dump the cx23418's '843 register space (from 0x0 - 0x9ff) with > v4l2-dbg. However IIRC, the last time someone provided that for the red > screen problem, all the '843 registers looked OK. > > Regards, > Andy > > _______________________________________________ ivtv-users mailing list [email protected] http://ivtvdriver.org/mailman/listinfo/ivtv-users
