Casio IT-2000D - Manual (Page 15)

15
2. Basic Software
2.1 Overview
2.1.1 Software Configuration
The following diagram shows the software configuration of the IT-2000.
Fig. 2.1
Note: The PenMouse driver and Keypad driver cannot co-exist on the system.
Application
Layer
MS-DOS
Layer
Hardware & BIOS
Layer
Application
Int33h
Keypad Library System Library OBR Library
MS-
DOS
Keypad
Driver
PenMouse
Driver
System Driver
ROM BIOS
AT Architecture + Original Hardware
Pen BIOS Extended BIOS APM BIOS