This class provides, within an electrical computer or digital data processing system, for the following subject matter:
A. Processes and apparatus for addressing memory wherein the processes and apparatus involve significant address manipulating (e.g., combining, translating, or mapping and other techniques for formatting and modifying address data) and are combined with specific memory configurations or memory systems;
B. Processes and apparatus for accessing and controlling memory (e.g., transferring and modifying address data, selecting storage devices, scheduling access); and
C. Processes and apparatus for forming memory addresses (e.g., virtual memory addressing, address translating, translation-lookaside buffers (TLBs), boundary checking, and page mode).
SCOPE OF THE CLASS
(1) Note. In the instance where a peripheral is a memory, classification herein is proper. (2) Note. Classification herein requires more than nominal recitation of addressing techniques or of memory accessing or controlling in combination with digital data processing systems or data processing. A nominal combination refers to a combination wherein one or more of the means or steps thereof are recited so broadly, and without details, as to constitute a mere identification rather than a description of each means or step. (3) Note. Memory devices, per se, are classified in their respective device classes. More specifically, registers and data bearing records (e.g., smart cards) are classified elsewhere. Static memory devices including internal elements of memories are classified elsewhere. Display memory organizations and structures (i.e., selective visual display systems) such as memories defined by graphics processing systems and graphics processing that involves interfacing with memory are classified elsewhere. Devices (e.g., printers) that include memory for processing data for static presentation (i.e., for viewing on a fixed medium such as paper) are classified elsewhere. Dynamic magnetic information storage or retrieval devices (e.g., magnetic disks, tapes, drums, etc.) are classified elsewhere. Dynamic information storage or retrieval devices (e.g., optical disks, CD-ROMs, jukebox mechanics, and other storage devices having magnetic and mechanical components) are classified elsewhere. See the SEARCH CLASS notes below. (4) Note. Processes and apparatus for transferring data between memories of different computers directly (i.e., with minimum or no intervention from main processors of the computers) are classified elsewhere. See the SEARCH CLASS notes below. (5) Note. Processes and apparatus for direct memory access (DMA) (i.e., the transferring of data between peripherals and memories of a computer or digital data processing system with minimal or no intervention from the main processor of the computer or digital data processing system) are classified elsewhere. See the SEARCH CLASS notes below. (6) Note. Processes and apparatus for accessing and retrieving instruction data of a fixed or variable length from a memory or buffer and for shifting such instruction data to align it with a physical memory or buffer boundary are classified elsewhere. See the SEARCH CLASS notes below.