I'm assuming you're using the stable bttv driver (v0.7.8) under 2.4.
The Imagenation PXC200 seems to have ADC disabled by default.
Try:
insmod bttv card=29
If that doesn't kill your card and if it works add the snipped of code
from bttv-cards.c init_PXC200() to you cards init code (default?):
btwrite(BT848_ADC_RESERVED|BT848_ADC__AGC_EN,BT848_ADC);
The bttv driver has support for signal strength detection, which can be
used to detect the presence of cameras. Maybe you could just disable the
dead cameras?
//assuming /dev/video device is opened
struct video_tuner vt;
ioctl(video_dev_fd,VIDIOCGTUNER,&vt);
printf("Signal Strength = [%d]\n",vt.signal);
Cheers,
Robert.
Dmitry Alexeyev wrote:
>
> Hello.
>
> I have BT878 card and external multiplexer with several monochrome cameras
> connected to it. If one camera is off ( blank screen ), bt878
> automaticaly increases brightness, so I can see nothing on frames from
> other cameras.
> How can i turn off AGC ?
>
> Dmitry
>
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