The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 11, 1997
Filed:
Dec. 16, 1994
Kenneth A Dockser, San Jose, CA (US);
VLSI Technology, Inc., San Jose, CA (US);
Abstract
A Harvard architecture data processing system includes a processor, main memory, an instruction cache, and a data cache. As is generally known with the Harvard architecture, these components are interconnected by an instruction bus, an instruction address bus, a data bus, and a data address bus. The instruction cache includes a branch target section and a general instruction section. For each instruction request by the processor, both sections are examined to determine if the requested instruction is in the cache. If it is, it is transmitted from the cache to the processor. If it is not, an instruction line including the requested instruction is fetched from main memory. If the requested instruction represents a jump (the result of an unconditional branch or a conditional branch the condition of which is met) the fetched instruction line can be stored only in the branch target section. If the requested instruction is simply the one located at the address one above that of the previous instruction, the fetched instruction line can only be stored in the general instruction section. This approach preserves branch targets in cache, while allowing all cached instructions to be available to the processor irrespective of whether a jump is called for.