[mythtv-users] Myth blowing up my M179 settings

Chris Thompson ct-myth at cthompson.com
Fri Mar 5 18:07:57 EST 2004

I have a backend box with a PVR-250 in the first slot, and two Aver M179's
in the next two slots. This is a FC1 box set up to Jarod's howto, using all
the software from ATrpms.

I'm feeding each card via SVideo-0. 

I was having trouble getting video in from /dev/video1, which is the first
M179. I rmmod'ed ivtv, did a modprobe, checked dmesg, and all was well.

I did the test_ioctls from Jarod, namely

# /usr/bin/test_ioctl -u 0x3000
# /usr/bin/test_ioctl -p 4
# /usr/bin/test_ioctl -f width=720,height=480
# /usr/bin/test_ioctl -v input=3,output=1

though I was doing -p 0 for Svideo-0.

cat /dev/video1 > foo.mpg works like a champ (sort of, see below)

in mythtvsetup I cleared all my capture card settings and added three new
ones on /dev/video0 video1 and video2. All were set to PVR-250/350. All
were set to default input Svideo0.

I try to watch live TV and get nothing. I quit out of frontend and backend
and do another cat /dev/video1 > foo.mpg again and get data errors.

I tried a bunch of different test_ioctl settings, to no avail.

So I rebooted the machine, did an rmmod on ivtv and all the other modules
related to it. Did the cat /dev/video1 trick to verify it worked. I then
saved the output of test_ioctl -a.

You can see this at http://cthompson.com/before.txt

I then did mythbackend/frontend, tried to view liveTV, errored out, and did
test_ioctl -a and saved those values to http://cthompson.com/after.txt

You can see a diff between these two at http://cthompson.com/diff.txt

What's interesting is that myth has rearranged the values under
VIDIOC_ENUMINPUT. Other interesting changes are

-	Bus info      : 0
+	Bus info      : 1


-bitrate     : 8000000
-bitrate_peak: 16000000
+bitrate     : 4500000
+bitrate_peak: 6000000

Am I missing something interesting about M179?

The other ugly thing that's happening is that all video on the first M179
is in black and white. I had this problem for a while on my PVR-250, but it
went away, and I attributed it to a bad SVideo cable.

Now, however, I can move the same cable back and forth between the PVR and
the M179 and the PVR gets color and the Aver doesn't.


Chris Thompson

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