please help ..The New DDE_USB is giving compilation errors...

tapas kundu tapaskundu1 at
Fri Apr 10 22:30:58 CEST 2009

Thanks for your help. Usb mouse is working now!! ..  I have gone
throush USB CAM folder. Could you please tell me which file contains
usb driver for your CPIA webcam. I have seen 1 folder named "contrib"
under usbcam directory. I think that it  contains lots of linux usb
webcam drivers under directory
"l4/pkg/usb/examples/usbcam/contrib/linux/drivers/media/video" .

I didn't understand make files in every directory. Could you please
explain compilation procedure without using make files. What is the
use of contrib directory under usbcam folder? Please let us know which
files are responisble for usb webcam device driver function.

I am a beginner . Please help me.


On Fri, Apr 10, 2009 at 4:43 PM, Dirk Vogt <dvogt at> wrote:
> Hi,
>> 1) For usb camera a dope has started and a small menu has came showing
>> "usbcam" and "exit". But it is not showing anything when I am clicking
>> on usbcam.
> That's the normal behavior of usbcam, when it does not find a usbcam.
> However you should see in the debugging console that usbcore and have
> usbcam are initialized.
> When usbcam recognizes a new cam, a new button video0 will appear. By
> clicking this button usbcam will start the video capture.
>> 2) For usbhid , we have connected a usb mouse . But it was not
>> working. Here is the menu.lst , I have used for usb mouse.
> It seems you forgot to put usbcore into your menu.lst.  Remember, DDEUSB
> uses a client/server approach to offer USB functionality.  The usbcore
> is the only one to touch the host-controller hardware and thus needed
> for all other USB drivers.
>> Please know that we have a plan to add support for new webcams .
>> Please let us know following information :
>> 1) Please provide us the menu.lst which you have used for usbcam and usbhid.
> They do not differ much from yours.
>> 2) I have found following files under directory
>> "/home/tapas/10AprilUserbuild/source/pkg/usb/examples/usbcam/src"
>> main.c , support.c , usbcam.c  and libv4lconvert (directory)
> Actually usbcam.c is just containing the gui and the v4l and v4l2
> capturing code. The first should be documented somewhere in the dope
> package and for the second there is plenty of documentation including
> small examples spread all over the world wide web.
> the libv4lconvert was taken from libv4l [1] and was needed to convert
> the data from the video device from e.g. jpeg to the vscreen's pixel
> format.  Further, support.c implements some functions the were needed by
> linux kernel part of V4L.
> If you have a look at the makefile, you can probably see how to add
> support for new usbcams.
> Good luck,
> Dirk.
> [1]

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