Security is an important issue within the development of integrated circuits. Components and information within these integrated circuits require some way to provide access protection to protect the integrity of these systems. A security system of some form is usually implemented to prevent unauthorized access to particular locations of integrated circuits such as components (e.g. memory) of a data processing system. Trusted software developers are authorized users responsible for all applications on an integrated circuit such as a data processing system. They know of the existence, location, and use of every component and feature within the data processing system. In general, when a data processing system is released to the public, full disclosure of all the features is not given to the general public. They are only informed of those elements that apply to their needs and uses of the integrated circuit. Therefore, these authorized software developers, by having full access to the system, are responsible for all applications within the data processor while only limited information is given to the general users.
A problem arises when unauthorized users access portions of the system that are not available to the general public. These unauthorized users can therefore achieve access to important components and violate the security of the system. This violation gives the unauthorized users important information concerning data or functions within the system, and this information can be detrimental to an integrated circuit such as a data processing system. A technique used to secure portions of a data processing system is to generate an exception fault anytime an access fault is detected. This exception fault is then handled by a software exception handler in a prior art manner. A large problem with a software exception handler arises when unauthorized users detect this software security feature and possibly trace the software in the handler. Unauthorized users can achieve unlimited access and can even override the handler in order to access protected components of the data processor or other integrated circuit. The software exception handler is very susceptible to penetration; therefore, a need exists for a more secure method to prevent unauthorized access to information stored in an integrated circuit.