Dear Jithendran!
JITHENDRAN A schrieb:
Hello,
We are developing a VoIP enabled WiFI mobile handset using PXA255 running
Triton Linux 2.6.10.We have enabled the RNDIS gadget in the kernel for the
Ethernet over USB functionality
When the handset is connected to the USB port of Windows XP host, the USB
peripheral will enumerate to the host as an Ethernet device . However the
network connectivity is lost frequently with the message
"UDC:USB Reset" in the device side when VoIP activity is happening or the
host is used for browsing internet/download.
We are using the standard RNDIS drivers bundled with the XP distribution.
This behaviour CAN also be related to hardware problems:
- bad isolation between RF and USB part
- ground "ringing" due to current spikes caused by the RF transmitter
- current spikes causing USB supply breakdown
If you device is USB bus powered you should mount some big low-ESR
capacitors onto the power supplies, using very short leads. Use an
oscilloscope with a high frequency current probe to check if there
are spikes on the USB ground and supply lines. Some filters for USB
data signals cause more problems than they solve; try to by-pass
them; instead try some ferrite beads.
With best regards
Andreas Schweigstill
--
Dipl.-Phys. Andreas Schweigstill
Schweigstill IT | Embedded Systems
Schauenburgerstraße 116, D-24118 Kiel, Germany
Phone: (+49) 431 5606-435, Fax: (+49) 431 5606-436
Mobile: (+49) 171 6921973, Web: http://www.schweigstill.de/
-------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc. Do you grep through log files
for problems? Stop! Download the new AJAX search engine that makes
searching your log files as easy as surfing the web. DOWNLOAD SPLUNK!
http://ads.osdn.com/?ad_id=7637&alloc_id=16865&op=click
_______________________________________________
linux-usb-devel@lists.sourceforge.net
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
