The [Drivers\PCMCIA\Driver] Key

The name of a generic device driver can be a subkey of the Drivers\PCMCIA key, and are used in conjunction with drivers listed within the [Drivers\PCMCIA\Detect] key. Such Driver subkeys are similar to the [Drivers\PCMCIA\Plug-and-play ID] keys with respect to the values they contain.

Values for this subkey are described in the following table. Additional values can be stored for purposes specific to the device.

Value name Value type Description
Dll REG_SZ This required entry specifies the filename for an driver DLL the Device Manager is to load.
Prefix REG_SZ The Prefix value, if it exists instead of Entry, specifies the device driver's device filename prefix. It is a three character identifier, such as "COM".
Index REG_DWORD Optional. Specifies the device index (0 through 9). The Index value specifies the index assigned to the driver. If the Index value is not present, the Device Manager assigns the lowest index value available. This index will be associated with the device (for example, PGR1). Only index values 0 through 9 are allowed. Let the Device Manager determine the index value.
Context REG_DWORD Optional. Specifies the device context. If the Context value is present (that is, if it was initialized by the device's setup application), the Device Manager passes it as the dwInfo parameter to RegisterDevice. If it is not present, a pointer to a string containing the registry path to the device's Active key is passed as the parameter. The driver's initialization function can then open this key to read its information. To let the driver read the Active key data, you should not initialize the Context value.
Ioctl REG_DWORD Optional. Specifies an optional I/O control code the Device Manager sends to an installable driver. If the Ioctl value is present, the Device Manager opens the loaded driver and calls its stream interface I/O control function. The Device Manager passes the I/O control code specified by the Iocl registry. The driver can do any necessary post-initialization in this context. For example, the driver could load modules that will use the device.

In addition, the Device Manager broadcasts a WM_DEVICECHANGE message for the new device and it signals the application notification system via the PegEventHasOccurred function, passing it the NOTIFICATION_EVENT_DEVICE_CHANGE event.


For example, RAMCard is the name of a driver that does not have a Plug and Play ID.

HKEY_LOCAL_MACHINE     [Drivers]         [PCMCIA]             [RAMCard]                 SZ: Prefix = RAM                 SZ: Dll = RAMCARD.DLL