Frequently asked questions about HII

Table of Contents What is VFR? What is VFR class & subclass? Are VFR generated manually or with tools? Can PEI check options set in NVRAM, that is, with PCDs? Where is an example of using HII and VFR ?

Visual Forms Representation (VFR) it is a language like syntax for describing forms and pages used for setup like screens. VFR is compiled and produces Internal Forms Representation (IFR) The VFR Spec can be downloaded from the EDK-II-Specifications page

Visual Forms Representation (VFR) Class and subclass described in a FormSet definition.

• Valid Class names are: "NON_DEVICE" ,"DISK_DEVICE", "VIDEO_DEVICE", "NETWORK_DEVICE", "INPUT_DEVICE", "ONBOARD_DEVICE", "OTHER_DEVICE"

ii.

• Valid SubClass names are: "SETUP_APPLICATION", "GENERAL_APPLICATION", "FRONT_PAGE", "SINGLE_USE"

Currently the VFR files are generated mostly manually with a text editor.

Yes, the PCDs need to be declared as DynamicHii

There is a good example in the MdkModulePkg\Universal\DriverSampleDxe. To see the demo of this use the Nt32 emulation setup page, go to "Device Manager" then "Browser Testcase Engine". This will open a menu form with examples of different types of ways to enter configuration data.