The name of a generic device driver can be used as a subkey of the Drivers\PCMCIA\ key in conjunction with drivers listed within the Drivers\PCMCIA\Detect\ key. Such Driver subkeys are similar to the Drivers\PCMCIA\Plug-and-Play-ID key with respect to the values they contain.
The following table shows the values for this subkey. Additional values can be stored for purposes specific to the device.
Value name |
Value type |
Description |
| Dll | REG_SZ | This required entry specifies the file name for an driver DLL that the Device Manager is to load. |
| Prefix | REG_SZ | The Prefix value, if it exists instead of Entry, specifies the device file name prefix of the device driver. It is a three-character identifier, such as COM. |
| Index | REG_DWORD | Optional. Specifies the device index. 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. Only index values from 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 the RegisterDevice function. 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 then can open this key to read its information. To let the driver read the Active key data, do not initialize the Context value. |
| Ioctl | REG_DWORD | Optional. Specifies an optional I/O control code that the Device Manager sends to an stream interface driver. If the Ioctl value is present, the Device Manager opens the loaded driver and calls its I/O control function. The Device Manager passes the I/O control code specified by the Iocl registry. The driver does any necessary post-initialization in this context. For example, the driver loads modules that use the device.
In addition, the Device Manager broadcasts a WM_DEVICECHANGE message for the new device and signals the application notification system by means of the PegEventHasOccurred function, passing it the NOTIFICATION_EVENT_DEVICE_CHANGE message. |
For example, RAMCard is the name of a driver without a Plug and Play identifier. In addition to being listed within the Drivers\PCMCIA\Detect key, this driver would also have a subkey within Drivers\PCMCIA\ to store values as shown in the following example.
HKEY_LOCAL_MACHINE
[Drivers]
[PCMCIA]
[RAMCard]
SZ: Prefix = RAM
SZ: Dll = RAMCARD.DLL