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Posts: 5
Registered: ‎02-08-2017

CP210x - not assigning Com Port

Hi,

 

We have a customer computer where the driver has installed successfully, but our device is not being assigned a Port number.  I've never seen this before.  It simply lists under ports as 'CP210x USB to UART Bridge' with nothing after it.   

 

Any help to identify and resolve this issue would be greatly appreciated.   The computer appears to be a Windows 10 computer.

 

If I attempted to change the COM Port, it would cause the snap-in Console to crash.

 

Thanks,

Chuck 

 

Posts: 2,322
Registered: ‎10-14-2014

Re: CP210x - not assigning Com Port

@p3_chuck

It is hard to give suggestion based on this limited information. Could you provide more detailed information and allow me to ask several question.

1 I think the issue only happen on this specific PC.

2. Is this a product made by yourself which have a CP210x component? If you have Silabs CP210x DK board, does the issue happen with the DK board?

3. Do you customized the driver? Do you customized the CP210x?

4. Do you see any error code?

5. Does these KBs help to troubleshooting the issue?

http://community.silabs.com/t5/Interface-Knowledge-Base/Troubleshooting-a-Product-Using-a-CP210x-USB...

http://community.silabs.com/t5/Interface-Knowledge-Base/Troubleshooting-Basic-USB-Enumeration-Proble...

WeiguoLu
Posts: 5
Registered: ‎02-08-2017

Re: CP210x - not assigning Com Port

Answers to your questions:

 

1 - yes, this is the only PC that I've seen it not assign a COM Port to the device.   The hardware has thousands of units in the field over that last 10 years.

 

2- Yes, we are the manufacturer of the product with a CP210x chipset in it.   We do not have a CP210x DK board.

 

3-  We do not customize the driver in any way.   We use it stock as released by SiLabs.   The only change we make to the CP210x is that we change the serial number to match the serial number of our PCB and we lock the device.

 

4-  There is no error code that I have found.

 

5-  No they did not help.

Posts: 2,322
Registered: ‎10-14-2014

Re: CP210x - not assigning Com Port

very strange, but it was difficult to guess the root cause based on these information.
if you have maybe you could try a USB analyzer to check the signal and compare it with the normal case.
by the way, maybe you could upload yhe schematic (pdf prefered) and someone could have a look if this hardware related.
WeiguoLu
Posts: 5
Registered: ‎02-08-2017

Re: CP210x - not assigning Com Port

Thanks for your reply.   We do not have a USB Analyzer and this is on a customer's computer so we do not have physical access to the computer (only scheduled Remote Connections).

 

It should not be relative to our physical hardware as we have been selling this same product for 10 years and have not had this issue.   Somewhere it has to be with the driver and the way it is communicating with this particular customer's computer.

Posts: 3
Registered: ‎02-26-2017

Re: CP210x - not assigning Com Port

Hello,

same issue on my side. Thinkpad T460 with intel USB host. Windows 10 home 64bits.

 

The device board uses CP2102. VID 10C4 and PID EA60 unchanged, serial = 0001.

USB driver properly installed.

The com port should appear at the end of "Silicon labs .... UART Bridge"

Properties, advanced, shows COM1 which is obviously incorrect.

When I try to change it, a window pops up Microsoft Management Console  crashed.

 device image

 

There is no entry  in registry HKLM\hardware\devicemap\serialcomm as it should.

 

The links provided to knowledge base by delu did not help to solve the issue. USBview and USBdeview did not help. Reinstall the driver and countless reboots neither.

 

Note that the same device with CP2102 works perfectly on an HP laptop,

The HP laptop uses same OS, also USB3 intel host. The only difference I could find is that the HP laptop has the previous generation Intel chipset (serie 9) and the Thinpad T460 uses the latest (serie 100).

My conclusion is similar to p3_chuck. It must be related to the Silabs driver interaction with Windows 10 with intel USB3 implemention.


Any help ?

thanks

Posts: 5
Registered: ‎02-08-2017

Re: CP210x - not assigning Com Port

Any update/ideas/suggestions on this?   I have a customer who has spent over $1000 on our hardware that currently cannot use it due to this issue.

Posts: 3
Registered: ‎02-26-2017

Re: CP210x - not assigning Com Port

It works again on my Thinkpad.
I reinstalled a system backup made prior to the first time I plugged this device.
With a clean windows install, I  plugged the board and let windows 10 find the driver.
Curiously, w10 installed automatically an older driver 6.7.0 from 19.3.2014. The board is properly installed, the com port number is visible in the device manager and it works as expected.

 

Previously, I installed manually the latest driver 6.7.4.261 from the website.

I won't try to update manually the driver Robot wink

Posts: 3
Registered: ‎02-26-2017

Re: CP210x - not assigning Com Port

ps: my HP laptop also has 6.7.0 driver

Posts: 5
Registered: ‎02-08-2017

Re: CP210x - not assigning Com Port

I have removed all traces of the driver that can be removed.   They didn't show in the registry, pnputil, etc.  But it still will not assign a COM Port when installing any driver.  I've tried 6.7.1, 6.7.3 and 6.7.4

 

Any help would be appreciated.  Although this is the first time I've seen this issue not easily resolved by driver uninstall & reinstall, I need to find a suitable solution for this customer.

 

Wiping the entire computer would not be a suitable solution.