USB-232 with USB extenison dosen't work

[dweriksson]

I am trying to use a USB extension on a USB-232 adapter on a Kollmorgen amplifier.

When I  plug the USB-232 directly in to the USB port on the computer I have no problems communicating with the amplifier.

When I use an extension on the USB and try to communicate with the amplifie, I get a blue screen and it crashes the computer.

Unfortunately I cannot extend the RS232 side.

Has anyone seen this or know what I can do to fix this problem?

Thank You in advance

[EadieU]

The signal integrity decreases with passive USB extension cables, so that could be where the problems are coming in.  One thing you can try is a third-party product called an active USB extender.  You can see information about the use of them with one of our other USB devices in this NI KnowledgeBase article: Extending the USB Cable for a GPIB-USB-A

I have not tested an active USB extender for the USB-232, but it is something you could try.  

Regards,

Mark E.

Applications Engineer

National Instruments

[JasonSmith]

What kind of USB extender are you using? Is this just an extension cable, a long-distance powered extender, or a network/wireless extender of some sort? Also, when you say USB-232, do you mean the USB-232 sold by National Instruments, or is this a third-party serial adapter?

If this is a National Instruments USB-232, you should make sure that you have NI-Serial 3.4 installed. NI-Serial 3.4 included a greatly improved driver for our USB Serial interfaces, so if you are using an older version you may benefit from upgrading to version 3.4.

Finally, does the blue screen mention the name of the driver which is causing problems? If the crash is occurring in the NI-Serial USB-232 driver, the driver name should be NiUsbSer.sys or NiSerU.sys, depending on your version of the driver. If your extender is something that requires a driver to be installed, it could be the source of the blue screen as well.

-Jason S.

Message Edited by JasonS on 02-04-2009 05:56 PM