2 operation method – Casio IT-2000W User Manual
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7.7 System 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.
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
Application Program
System Library
Virtual Keyboard Driver
Windows
BIOS and Hardware
Keyboard Controller