Browse Prior Art Database

Dynamic Determination of System Operation

IP.com Disclosure Number: IPCOM000038597D
Original Publication Date: 1987-Feb-01
Included in the Prior Art Database: 2005-Jan-31

Publishing Venue

IBM

Related People

Authors:
Chiang, DL Krishnamurty, R Nunn, CR [+details]

Abstract

A method is described which allows a system to determine how a coprocessor operates by changing the code that will be executed when the coprocessor is reset. The coprocessor card has no ROM (read-only memory) on it. It uses system RAM (random-access memory) or RAM plugged into the system bus. When the processor on the coprocessor card is reset, it begins executing code at segment address X'F000' offset X'FFF0'. As this is in the range of memory that is read/write to the system, the system determines what function the coprocessor performs based on what code is placed in that location. Thus, the operation of the coprocessor system can be dynamically determined at coprocessor start time.