Hello,
I've recently been working on a Linux system with two video input
cards, both of which now have a v4l driver. I can get each of them
to work independently without a problem. However, when I try to
run both of them at the same time, the one I start first works
fine, but the one I start second doesn't.
Running xawtv for the first device runs fine:
% ln -s .xawtv-wintv .xawtv
% xawtv
This is xawtv-3.73, running on Linux/i686 (2.4.18-3smp)
WARNING: Your X-Server has no DGA support.
seteuid(root): Operation not permitted
v4l-conf had some trouble, trying to continue anyway
and I now get an image, and can change channels/inputs just fine.
Running xawtv for the second device results in the following
messages:
% rm .xawtv
% ln -s .xawtv-lml33 .xawtv
% xawtv -c /dev/video1
This is xawtv-3.73, running on Linux/i686 (2.4.18-3smp)
WARNING: Your X-Server has no DGA support.
seteuid(root): Operation not permitted
v4l-conf had some trouble, trying to continue anyway
ioctl: VIDIOCSCHAN(0,Composite,flags=0x0,type=2,norm=2): Operation not supported
WARNING: v4l and x11 disagree about the screen size
WARNING: Is v4l-conf installed correctly?
WARNING: v4l and x11 disagree about the color depth
WARNING: fbuf.depth=0, x11 depth=32
WARNING: Is v4l-conf installed correctly?
WARNING: overlay mode disabled
and a blank screen.
In this case, the two video cards are different models. One is an
LML-33, the other a WinTV Theater. I don't have a machine with
two of the same card to determine whether this makes any difference
(perhaps someone else knows). I did try starting the cards in
the opposite order as well, with the result that the lml33 card
worked, and the wintv card gave a blank (black) screen.
And, I almost forgot to mention: I'm running a basic RedHat7.3
installation (kernel 2.4.18-3) on a dual Athelon machine with
of course the two video boards. I just compiled the "cvs-latest"
zoran driver from the www.cicese.mx/~mirsev/Linux/DC10plus
webpage -- this is more recent than the 0.8 driver on mjpeg.sf.net.
Has anyone had any experience positive or negative with multiple
cards in the same machine? (The installation does make 4 video
devices as /dev/video{0-3} afterall.)
Also, as may be obvious from above, it would be really nice if
xawtv and other v4l tools could allow one to specify the name
of the config file as a command line argument (or an environment
variable, or even better by automatically detecting the type of
device and appending it to the config file name). I may contribute
this myself at some point, but right now my task is to get them
working.
Thanks for any hints and other help,
Bill
/*************************************************************************/
/* Bill Sherman (wsherman@xxxxxxxxxxxxx) */
/* National Center for Supercomputing Applications */
/* University of Illinois at Urbana-Champaign */
/* Og - "You want to do mankind a real service? Tell funnier jokes" */
/* Spinner - "but facts don't always reveal the truth" */
/* Robin - "Yeah, but I always figure that's the writers' fault" */
/*************************************************************************/
