Re: Driver Load Sequence

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Thanks Steve. The problem is that detaching the external device from the USB
port doesn't un-load the driver, the driver gets stuck in somehow as if the
OS doesnot know that it is there. But this only happens if WinCE is started
with the USB device attached to the USB port otherwise everything works fine.
When the WinCE device is booted with the external FTDI device physically
attached to the USB, the Host driver loads the FTDI_SER.DLL at boot time. The
problem is that under this senario the Host Controller can not un-load the
driver when the external device is detached. In a way the OHCI driver gets
stuck and it wouldn't work properly either. Basically the WinCE device can
only handle the external USB device properly if it is attached after
completion of the boot up sequence.
So to resolve this problem i need to tell WinCE not to load the FTDI driver
until every other DLL is loaded and boot up sequence is complete.
Alternatively if it is not possible to tell wince to load the driver until
after system boot, i need to somehow un-load the ftdi driver as soon as it
gets loaded during the system boot up and let the boot up sequence finish and
then load the ftdi driver. Maybe i could write a script that runs at start
up, but by what i read from your post doesnt look like that can be doen
programatically, something using insmod and rmmod in unix like OSs.

Regards,
EZ.

"Steve Maillet (eMVP)" wrote:

> You can't programmatically load/unload USB client drivers only the USB host
> driver can do that. Just unplug the device and the host driver will unload
> the client driver.
>
> --
> Steve Maillet
> EmbeddedFusion
> www.EmbeddedFusion.com
> smaillet at EmbeddedFusion dot com
>
>
>
.

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