On Thursday 22 July 2004 01:51 pm, Alan Stern wrote: > On Thu, 22 Jul 2004, Kyle Harris wrote: > > I have a check scanner device (serial function): > > > > P: Vendor=1136 ProdID=3231 Rev= 1.00 > > S: Manufacturer=CTS Electronics > > S: Product=USB CTS LS100 > > > > If setup requests 8 bytes during the initial get_descriptor the device > > will return 8 bytes, but then continously NAKs the following OUT > > transaction. If I request 18 bytes initially, everything works fine. I > > have tested this on 2 different linux platforms. > > > > I borrowed a windows box. The sequence there is that a get_descriptor is > > sent before the set_address with an initial request of 64 bytes. Then the > > hc sends a set_address followed by get_descriptor with a request for 18 > > bytes. This sequence works. > > > > Is anyone familar with this scenario? Any suggestions on how to handle > > it? An initial get_descriptor of 18 bytes breaks other devices, so that > > is not an option. > > > > Thanks for any help, Kyle. > > This is very interesting. How did you determine the sequence of packets > sent by Windows?
I have a USB Tracker. It's not very sophisticated (cheap$), but does show frame data. I can send you a screen grab of the output (didn't buy the export feature), if that would be helpful. The sequence on Windows is: SE0 GetDescriptor SETUP IN (8 bytes) OUT SE0 SetAddress SETUP IN GetDesciptor SETUP IN (8 bytes) IN (8 bytes) IN (2 bytes) OUT several GetDescriptor frames follow > Is it always the same, or does it differ depending on > the speed of the connection? How do I control the speed of the connection? > What version of Linux are you using? I'm running 2.4.18-6mdk on my desktop and 2.6.0-rmk2 on a PXA-255 system. I prefer to work on the PXA platform, since that is where it needs to work. > I can send you a patch for one of > the more recent 2.6 kernels to implement the scheme you described. That would be fantastic! Thank you very much! Kyle. ------------------------------------------------------- This SF.Net email is sponsored by BEA Weblogic Workshop FREE Java Enterprise J2EE developer tools! Get your free copy of BEA WebLogic Workshop 8.1 today. http://ads.osdn.com/?ad_id=4721&alloc_id=10040&op=click _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
