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Re: [LUG] (OT) USB Device development



On Wednesday 12 November 2003 20:22, paul wrote:
> Thats the beauty of open source you can hack it as much as you want, why
> don't you contact the usb developers, for the kernel and ask what resources
> they use,  they may then be able to help you further.
>

Well after geting very dispondent yesterday, a day hacking in the linux kernel 
has proved invalueable!. Adding extra debug (to the kernel) allowed me to see 
what my device was sending and where the errors were and i have acheived full 
enumeration now. 

I have noticed a few things between windows and linux's USB. windows is *very* 
sensitive to the timing of the set_address() command, while linux is more 
relaxed and windows and linux enumerate devices differently. windows requests 
a device_descriptor of 40 bytes, then the correct size, then does a 
set_address. Linux does a set_address , then a get device_descriptor of 8 
bytes followd by the correct size. Windows also has those stupid .inf device 
descriptors and *zero* debug information( but i knew that already!).

At one point today we considered only supporting linux :-), as windows was 
being such a pain in the ass.

Regards

Robin


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