1. Field of the Invention
The present invention generally relates to methods and apparatus for electronically and securely configuring hardware features and options and, more particularly, to a configuration which contains a predetermined code or encryption sequence on a computer chip which is used to selectively enable the function features of the chip.
2. Description of Related Art
At present, it is standard for a variety of models of computers to be offered, each with different capabilities and features. This is true for each type of computer, from a personal computer to large mainframe and super computers. However, this wide variety of choices results in the requirement that each variation and model must be manufactured and kept in inventory.
In particular, it is common for a specific computer to be offered with various configurations of a multichip module or single chip assembly which each include different features and capabilities. Each module or chip assembly could include different numbers of control processors and feature chips. At present, each configuration of a module or chip assembly is manufactured and must be stocked in inventory to meet the demands of customers who desire the option of variations in functional characteristics or capabilities of a computer system. However, it is apparent that computer manufacturers would realize large efficiencies and economies by reducing the number of models manufactured.
In addition, a computer is generally sold with a particular configuration which meets the current needs of a computer user. The computer can usually be upgraded, modified or repaired as needed to meet the increased needs of the customer. At present, it is common for a new hardware unit to be added to the computer system to upgrade the hardware features or options. Often, a new or additional multichip module must be installed. The installation of the new hardware often must be performed off-site and so the customer must do without the computer system while the appropriate hardware is added or removed. In other instances, the configuration can be done on site but requires extensive configuration of the hardware. The loss of the use of the computer can result in financial loss and usually causes an interruption in the customer's business. Furthermore, similar problems result from failures in hardware elements.
In the past, off chip configurations have been used to store information for enabling features of a circuit. However, these systems are not completely secure since the information or code can be intercepted from the chip interface. In addition, a separate key chip can be used to provide security for single chip modules. The single chip modules are becoming more common as the density of a chip increases, so that multiple processors and/or features are present on a single chip.
Therefore, methods and apparatus which allow for the implementation of numerous combinations of functional characteristics or capabilities for a computer system or a multi chip module would be advantageous. It would also be beneficial to perform the configuration electronically and securely.