We have a USB device plugged into a CF USB host adaptor on the Pocket PC.
We wrote a driver for the PPC 2003.
On the PPC 2003 1st edition PPC, when the PPC goes through power off/on
cycle, the PPC will re-enumerate the USB device correctly with the new
¡°Hnd¡± value in the registry key
[HKEY_LOCAL_MACHINE\Drivers\Active\33].
In other words, every time the 2003 1st Edition PPC goes to the power off/on
cycle, the ¡°Hnd¡± value at the above key will be refreshed with a new
value, this seems working correctly.
While in the case of PPC 2003 2nd edition (we used Dell x50), after a Power
off/on cycle, the ¡°Hnd¡± value at the above key will NOT be updated and
stays the same as that of before Power off, and our USB device will NOT be
re-enumerated.
Our questions are,
Would anybody tell what cause this problem? Is this caused by the newer PPC
OS turning on the sleep mode of the USB device while the OS can not wake up
the USB device from the sleeping mode?
Are we missing something in the routines XXX_PowerDown and/or XXX_PowerUp
and/or in the IOControls such as IOCTL_POWER_CAPABILITIES?
Any instructions/helps will be appreciated.
Frank