Casio IT-2000W manual Virtual Keyboard Driver Function

7.6Virtual Keyboard Driver

7.6.1Function

The Virtual Keyboard Driver (VKD.386) is a driver that enables access to the keyboard controller on Windows (refer to Chapter 6 "Keyboard Controller"). This driver is only called from the system library. Since this driver has no chance of being directly called from the application program, the user does not have to be aware of its existence. Some of the system libraries use the functions of the keyboard controller. However, Windows applications cannot directly access the hardware. Therefore, they use this virtual keyboard driver to access the keyboard controller assuming that it is a virtual machine. The relationship between the virtual keyboard driver and application programs is shown in the following diagram.

Application Program

Windows

System Library

Virtual Keyboard Driver

Keyboard Controller

Fig. 7.4

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