The Device Manager uses registry keys that are stored in the HKEY_LOCAL_MACHINE\Drivers\key. The following are the major subkeys of the HKEY_LOCAL_MACHINE\Drivers\key:

Active\

The Active\key contains subkeys that track currently active drivers that were loaded by the Device Manager. Device driver setup routines should not modify the Active\key's contents, nor should they rely on the presence of any specific values within the Active\key.

When a device driver is loaded, the Device Manager passes the device driver the path to its Active\key as the dwContextparameter in the device driver's XXX_Initfunction. The device driver can rely on the presence of the following values:

• Hnd

  Device handle from the RegisterDeviceor ActivateDevicefunction. Please note that in Windows CE 3.0 and later, RegisterDevicehas been replaced with ActivateDevice.

• Name

  The device driver's Device File Name, for example "COM1:" or "SCR7:".

• Key

  Registry path within HKEY_LOCAL_MACHINEto the device driver's Builtin\or PCMCIA\key

  The Active\key for PC Card device drivers has the following additional values:

  • PnpId

    Plug and Play identifier string

  • Sckt

    Current socket and function pair of the PC Card

    Device drivers should never modify any of the values in this part of the registry that are put there by the Device Manager. Once a device driver is loaded, it can add values to its Active\key. However, the Device Manager will delete the device driver's Active\key and any values in it when the device driver is unloaded.

    Builtin\
    The Builtin\key contains subkeys that control which device drivers to load when the system starts up. Each driver-specific subkey can have the following values, some of which are optional:

    • Dll

      The name of the device driver's .DLL file.

    • Prefix

      The device driver's Device File Name Prefix.

    • Index

      The device driver's Device File Name Index.

    • Order

      The loading order for this device driver. The Device Manager loads device driver according to their Order numbers, starting with 0. This value is optional.

    • FriendlyName

      A string containing a human-readable description or name for the device driver.

    • Entry

      The name of a function for the Device Manager to call to initialize the device driver. This value is optional. If this value is not specified, the Device Manager will initialize the device driver by calling its RegisterDevicefunction.

    • Keep

      If an Entryvalue is present, then the presence of a Keepvalue prevents the device manager from freeing the device driver DLL after calling the function named in the Entryvalue. The mere presence of a Keep value is sufficient; the actual value stored in Keepis irrelevant.

    • Ioctl

      If an Ioctlvalue is present, the Device Manager will call the device driver's IOControl function, as described in XXX_IOControl, after loading the driver.

    • Context

      The value passed in the dwInfoparameter to RegisterDevicewhen the device driver is loaded.

      PCMCIA\
      The PCMCIA\key contains subkeys that are related to PC Cards and their stream interface drivers. The most important information in these subkeys is the Plug and Play identifier of the PC Card, which corresponds to a specified driver.
      Detect\
      The Detect\subkey contains numbered entries that list DLL names and detection functions. The functions identify a generic stream interface driver for PC Cards with no Plug and Play identifier, or for PC Cards with an unknown Plug and Play identifier.
      Driver
      Driver subkeys, named after generic PC Card drivers, contain values that are used to load the drivers. The Device Manager creates individual Driver subkeys when a generic stream interface driver detection function indicates that it can drive a particular device. The existence of a Driver subkey indicates detection by a driver that has an entry within the PCMCIA\Detect\key.
      Plug-and-Play ID
      Plug-and-Play ID subkeys contain values that are used to load stream interface drivers for PC Cards. Typically, the setup routine for a PC Card driver creates these subkeys when the driver is installed on a Windows CE-based platform.
      

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       Last updated on Tuesday, July 13, 2004

      © 2004 Microsoft Corporation. All rights reserved.