Problem w/ USB Device CP2102-GM

[user]

Archived from groups: microsoft.public.windowsxp.basics (More info?)

I'm using a board with the USB-UART bridge CP2102-GM (SiLabs), which is
pre-programmed w/ vendor/product/serial ID, and it's being recognized in the
device manager on Windows 2000, however it doesn't work with Windows XP (does
not show up in the device manager).
What could be possible be different between 2000 and XP, that cause this
behavior?
The USB port on the XP PC is confirmed working, the right device driver has
been installed and is working, just this specific board is not being
recognized, whereas other (same) boards are working w/o problems. I'd assume
the problem to be with the USB chip, if Windows 2000 wouldn't work with it.

Thanks!

 

[Guest]

Archived from groups: microsoft.public.windowsxp.basics (More info?)

On Thu, 14 Jul 2005 08:01:03 -0700, <arcp wrote:

> I'm using a board with the USB-UART bridge CP2102-GM (SiLabs), which is
> pre-programmed w/ vendor/product/serial ID, and it's being recognized in the
> device manager on Windows 2000, however it doesn't work with Windows XP (does
> not show up in the device manager).
> What could be possible be different between 2000 and XP, that cause this
> behavior?
> The USB port on the XP PC is confirmed working, the right device driver has
> been installed and is working, just this specific board is not being
> recognized, whereas other (same) boards are working w/o problems. I'd assume
> the problem to be with the USB chip, if Windows 2000 wouldn't work with it.
>
> Thanks!

I know nothing about this hardware but did find this web page for the
company and the product:

http://www.silabs.com/tgwWebApp/public/web_content/products/Microcontrollers/Interface/en/interface.htm

If I'm reading it right, this should work with XP. Since you are more
familiar with this device, perhaps you will be able to find something more
useful on the site to help you with this problem.

--
Sharon F
MS-MVP ~ Windows Shell/User

 

[user]

Archived from groups: microsoft.public.windowsxp.basics (More info?)

Sharon,

thanks for your reply. The chip indeed works with Windows XP, and other
boards ("identical" board) with the same chip are working with XP, however
this one board is not.
What I need to dig into is, how Windows basically determines what driver to
choose for hardware. I can't even convince Windows XP to install the driver
for this board. So what information does Windows gather for the hardware in
order to choose a specific driver.

Thanks,

Marco

"Sharon F" wrote:

> On Thu, 14 Jul 2005 08:01:03 -0700, <arcp wrote:
>
> > I'm using a board with the USB-UART bridge CP2102-GM (SiLabs), which is
> > pre-programmed w/ vendor/product/serial ID, and it's being recognized in the
> > device manager on Windows 2000, however it doesn't work with Windows XP (does
> > not show up in the device manager).
> > What could be possible be different between 2000 and XP, that cause this
> > behavior?
> > The USB port on the XP PC is confirmed working, the right device driver has
> > been installed and is working, just this specific board is not being
> > recognized, whereas other (same) boards are working w/o problems. I'd assume
> > the problem to be with the USB chip, if Windows 2000 wouldn't work with it.
> >
> > Thanks!
>
> I know nothing about this hardware but did find this web page for the
> company and the product:
>
> http://www.silabs.com/tgwWebApp/public/web_content/products/Microcontrollers/Interface/en/interface.htm
>
> If I'm reading it right, this should work with XP. Since you are more
> familiar with this device, perhaps you will be able to find something more
> useful on the site to help you with this problem.
>
> --
> Sharon F
> MS-MVP ~ Windows Shell/User
>

 

[Guest]

Archived from groups: microsoft.public.windowsxp.basics (More info?)

On Fri, 15 Jul 2005 07:22:01 -0700, <arcp wrote:

> Sharon,
>
> thanks for your reply. The chip indeed works with Windows XP, and other
> boards ("identical" board) with the same chip are working with XP, however
> this one board is not.
> What I need to dig into is, how Windows basically determines what driver to
> choose for hardware. I can't even convince Windows XP to install the driver
> for this board. So what information does Windows gather for the hardware in
> order to choose a specific driver.
>
> Thanks,
>
> Marco
>

Hardware is not my strong point - knowing only what I need to know to keep
my system and the family's up and running well.

I believe that the chip on the device gets a chance to identify itself to
Windows. If the device cannot communicate that information, Windows tries
to identify it on its own. If it fails to do that, it will ask you to pick
the device type. In tandem with identification: If Windows has a driver, it
gets installed. If it does not have a driver, it asks you what you want to
do. A list of options appears including the opportunity to install drivers
from a driver disk.

When you've tried manually installing the drivers, is that before or after
the device is plugged in? If after, what method are you using to do so?
Device Manager> (device properties)> Change driver is the route I would go.
If any warnings appear, override them to force the installation of your
drivers.

If Windows has mis-identified hardware or installed less desirable drivers,
deleting/uninstalling the device from Device Manager is recommended.
Disconnect the device. Wouldn't hurt to restart at this point. Install the
drivers then attach device.

You still have the outstanding fact that this device works on all other
installations but one. May want to check that the Shell Hardware Detection
service (and any other hardware related services) are enabled.

Past this point, I can't help further and would suggest contacting the
hardware's tech support to see if this is indeed a bad unit.

Microsoft's Technet website has an online version of the Windows XP
resource kit. One of the chapters will describe device id and driver
installation with technical details:
http://www.microsoft.com/technet/prodtechnol/winxppro/default.mspx

More specific URL for "Managing Devices" (especially the "Driver Ranking"
section:
http://www.microsoft.com/resources/documentation/Windows/XP/all/reskit/en-us/prdh_dmt_zehg.asp

--
Sharon F
MS-MVP ~ Windows Shell/User