Re: interacting with USB drivers

If it's not detected, I'd say that you have a hardware problem, not a driver
problem. The USB Host driver is what would have the ability to detect
insertions of cards, find which driver it needs, etc.

Paul T.

"Juhi S" <JuhiS@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:21E02C63-6A8E-4234-A7A4-752D19865C73@xxxxxxxxxxxxxxxx
I have an data-acquisition application in which data-logging is
performed constantly and data is stored in a CF Card, which acts as the
primary data-storage device for the system.

The Windows CE image that i have loaded has support for automatic
detection of USB mass storage devices.

The User can retrive the data from the system (CF Card) thru USB Drive.

There is no screen or console , it is an industrial Controller.

The data acquistion goes on constantly , and the applicaiton
periodically polls the USB slot to see if the user has inserted any
USB Drive in it.

I am using a 4 m long cable for USB Pen drive. This is unavoidable!
The problem caused due to this is that the Pen Drive is sometimes not
detected byt he Win CE system. Once the pen drive is not detected, it is
never subsequently detected. I want to know which driver is responsible
for
this, and how I can trap any errors occuring in the USB detection
operation.
I know tht in case of any errors, the driver disables this device on tht
USB
port. But it allows the same device on the second USB port , and detectes
it
too. I observed this during internal testing,,,there is only one port at
the
client site though.
I think the bus enumeration feature of the USB Host driver disables this
device if it cannot detect it in some number of tries.

I was thinking of a solution in which I could clear any error that occurs
on
the USB port, so that the USB driver wud re-enable the device and detect
it.

How can I detect any errors that occur at the Port? How can i clear these
errors?

I am an application developer, with a very basic idea about device driver
programming. Can anyone guide me to a good place to start with?


.

Relevant Pages