> Hello,
>
> Kernel 2.4.20, 300MHz Goede GX1 CPU, OHCI USB
>
> I use pwc without compressor module and with Jave Media Framework
>
> If I load the system by loading a "big (500k)" file with vi, than the webcam
> stops.
>
> Sometimes I get a message in /var/log/messages:
> Jul 4 17:01:38 linux kernel: pwc Iso frame 0 of USB has error -18
>
>
> but often I do not get any unusual message, but I have a stoped webcam.
Hi Detlef,
I have a similar problem: I found out that accessing a CompactFlash
in PIO mode to much will cause the pwc to stop working. It usually
gives this kernel message:
"pwc_isoc_handler() called with status -75 [Babble (bad cable?)]"
The user process accessing the camera never returns from read().
Only removing the driver modules and re-inserting them will "solve"
the problem. (this is not a solution because reloading en initializing
the camera driver takes many seconds: I'm building a real-time image
processing application).
The problem can be triggered instantaneously by doing a:
cat /dev/hda > /dev/null
I'm not sure but I suspect that the problem is in the USB layer and
not in the Philips webcam driver.
Are you using CF too, or an other disk in PIO mode ?
PIO mode access will generate quite some CPU load in kernel mode,
it seems that the kernel doesn't serve the USB stuff fast enough.
In my application I don't care if some frames get lost or damaged.
But the halting of the camera is not acceptable.
greetings,
Rob van Nieuwkerk
Sysinfo:
--------
300MHz Geode GX1 (= Pentium compatible CPU)
various 2.4.x kernels
PCVC740K webcam
pwc compressor
OHCI
-------------------------------------------------------
This SF.Net email sponsored by: Free pre-built ASP.NET sites including
Data Reports, E-commerce, Portals, and Forums are available now.
Download today and enter to win an XBOX or Visual Studio .NET.
http://aspnet.click-url.com/go/psa00100006ave/direct;at.asp_061203_01/01
_______________________________________________
[EMAIL PROTECTED]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
