Got a reply on the Silabs forum which doesn't sound good....
Message:
<i>But when I plug the stick in, it forces the current driversetup to a new COMM port but gives an exclamation mark.
THere is still only one instance of the bridge and none of the devices work.
When I unplug one of them they work."</i>
This symptom sounds like same as this case,
"2 or more CP2102 in WinXP"
http://www.cygnal.org/ubb/Forum9/HTML/001270.html
In above thread, a customized VCP driver conflicts with the original one, because of an INF file trouble - the service name.
Preston of SiLabs posted as follows in the thread,
[blockquote]posted June 04, 2007 10:13 AM by preston, from SiLabs
This issue has been addressed in the Driver Customization Wizard v3.8, and has been updated on the application notes page as AN220SW.[/blockquote]
The XANURA and AEONLABS drivers may be old ones.
<i>"installed a fresh v5.4 but I can't get the two device working."</i>
XANURA and AEONLABS may apply custom VID/PID.
It's better to ask the manufacturers for new driver,
but if you can't wait for,
- Read out the descriptors from the CP2101s using USBView and get the VID/PID value
- Make custom drivers of the VID/PID
MS USBView on FTDI site
http://www.ftdichip.com/Resources/Utilities/usbview.zip
SiLabs MCU KB: CP210x Troubleshooting Techniques
http://portal.knowledgebase.net/article ... 010&p=4120
On this page, you'll learn how to use UVCView (USBView)
"C8051F32x and CP210x USB Driver Customization"
https://www.silabs.com/Support%20Docume ... /an220.pdf
https://www.silabs.com/Support%20Docume ... N220SW.zip