Abstract: In a computer for executing a computer program, apparatus and a method for updating information within a computer program instruction without interrupting execution of the computer program. The apparatus contains a memory for storing the information within the instruction at an address within the memory, circuitry for periodically accessing the information for execution by the computer, and circuitry for altering, between periodic accesses to the memory by the accessing circuitry, the information stored in the memory. In this manner, computer program execution is not interrupted to alter the information within the instruction. Typically, the information is a data field value contained within a computer microcode instruction. Consequently, the data field value is updated, but other information within the instruction such as an operational code (OPcode), is not altered by the update operation.

Abstract: A method and apparatus, within a computer system, for rotating and scaling an image using a three step process. The amount of image rotation and scaling is user defined. The three step process precisely rotates an input image to rapidly produce an output image. Specifically, the three step process shears each pixel location in the input image along a first axis, then shears and scales the sheared pixel locations along a second axis, and lastly, the sheared and scaled pixel locations are scaled along the first axis to produce an output image that is precisely rotated and scaled relative the input image. The apparatus and method disclosed find applicability in video servers, medical imaging, special effects and animation and location based entertainment systems among other applications.

Abstract: In a parallel processing computer containing a plurality of processors, each connected to a memory unit, a method and apparatus for accessing a distributed data buffer. Each of the processors within the computer executes a first routine for processing input data to generate output data. During processing, some or all of the data associated with the processing is temporarily stored within a predefined portion of each of the memory units that form a portion of the distributed data buffer. Upon occurrence of an interrupt signal, execution of the first routine is halted. Also, the status of the computer at the time the interrupt signal occurred is stored in memory. Thereafter, a second routine (an interrupt routine) is executed to access the data stored in the data buffer. Once the data is accessed, the status of the computer is restored in accordance with the previously stored computer status information.