Keyboard Controller Password Security Scan Code Filter
Original Publication Date: 1988-Jan-01
Included in the Prior Art Database: 2005-Feb-14
This article describes a keyboard security feature for a personal computer (PC) system utilizing a software technique. For an Intel* 80286- and also an 80386-based PC system which does not have a physical keylock to disable the keyboard while the system is on, a keyboard security feature through a software technique is disclosed herein. Between the CPU and the keyboard there is an Intel 8042 microprocessor which has the functions as follows: ~Performs the serial communication for the keyboard. ~ Performs the serial communication for the optional mouse. ~ Performs some data translation on the keyboard scan codes. ~ Provides some commands available to the system. ~ Provides a software keyboard lockout mechanism. The 8042 only receives scan codes from the keyboard.