Casio IT-2000W manual System Library main program file Function, Operation Method

7.7System Library (main program file)

7.7.1 Function

SYSCALL.DLL is a dynamic link library that constitutes the main program of the system library (refer to Chapter 8.6.2 "System Library"). Before executing an application that calls the system library it is necessary to locate this file in the Windows directory (or other directory to which the path is established). Some of the system libraries use the functions of the keyboard controller. However, Windows applications cannot directly access the hardware. Therefore, they use the 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.

Windows

Application Program

System Library

Virtual Keyboard Driver

Keyboard Controller BIOS and Hardware

Fig. 7.5

7.7.2 Operation Method

Copy the SYSCALL.DLL file into the directory to which the path is established. The setup file does not need to be modified at all. If Windows is installed by the installer, SYSCALL.DLL will be automatically copied into the "D:￿WINDOWS" directory.

For information about the method used to call SYSCALL.DLL from applications refer to Chapter 8.6.2 "System Library".

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