Objective Development Forums

Hi,Everybody
I want to convert usbasp programmer source project from WinAVR source to CodevisonAVR source.
Firmware is available from:
http://www.fischl.de/usbasp/
or directly:
http://www.fischl.de/usbasp/usbasp.2011-05-28.tar.gz

I change some code to Compatible code (WinAVR Code) to CodeVision but I have some problem.
There are some error while compiling the project:
"Linker error: ...Desktop\usbasp\usbdrv\usbdrv.h(213): function 'usbFunctionDescriptor' declared, but never defined"

function "usbFunctionDescriptor" is declare in usbdrv.h but not defined in usbdrv.c
this is the codevisonAVR source:
http://s5.picofile.com/file/8129945900/usbasp.rar.html
Can any body help me?
thanks alot

You need to implement this function ONLY if you provide USB descriptors at
* runtime (which is an expert feature). It is very similar to
* usbFunctionSetup() , but it is called only to request USB descriptor
* data. See the documentation of usbFunctionSetup() for more info.

look at this for more information about descriptor defining :
http://vusb.wikidot.com/examples