Thank you very much for the response.
The cable that we are using is a special one called "active cable".
An individual active cable measures 5m and it incorporates electronics at
the end to repeat the signal. Specifications say a maximum of up to 25 meters
(daisy chain of 5 active cables) can be extended. The
25m extension works quite successfully most of the time, the problem
occurs once/twice daily.
Regards,
Manjunath D
################################################################################################################
***************************************************************************************************************
On Tue, 29 Jun 2010, Felipe Balbi wrote:
Hi,
On Tue, Jun 29, 2010 at 10:37:09AM +0200, ext Manjunath Doddavenkatappa
wrote:
We have a sensor device with a USB connector (device's name is
TelosB in case if your aware of it). We use USB active cables to connect
such devices to a Linux PC (2.6.22-14-generic). Length of these active
cables range from 5 to 25 meters. Problem is while long 25 meter active
cables are used for connection. Communication with a device connected via
such a long cable is fine most of the time, but connection would go down
at least once/twice a day (although the corresponding /dev/ttyUSBX is
visible). Each time the connection is lost, removal and insertion of the
USB kernel module "ehci-hcd" will make the connection alright again
(modprobe -vr ehci-hcd; modprobe -v ehci-hcd).
Is there any way to fix this without having to remove and insert the
module every time. I am new to USB framework on Linux.
the cable length shouldn't be more than 5m with mini-usb and no more than 3m
with micro-usb connectors.
--
balbi
DefectiveByDesign.org
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
