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:
Sep. 16, 1997
Filed:
Sep. 26, 1994
Jonathan Fitch, Cupertino, CA (US);
Apple Computer, Inc., Cupertino, CA (US);
Abstract
An address selective address mapping system comprises an address translation circuit, a central processing unit (CPU), a data cache, and a memory. The address outputs of the CPU are coupled to a first address bus, while the address inputs of the data cache and memory are coupled to a second address bus. The address translation circuit's inputs are coupled to the first address bus, and the address translation circuit's outputs are coupled to the second address bus. The CPU sends a pointer address via the first address bus to the address translation circuit. The address translation circuit determines whether the pointer address indicates that the next source instruction is within the subset of the most frequently executed source instructions. If so, the address translation circuit maps the pointer address to an address within the data cache. If not, the pointer address is routed through the address translation circuit unchanged. The pointer address is next routed to the data cache and to the RAM via the second address bus. If the pointer address was mapped to a data cache address, the data cache outputs the pointer to the next emulation routine on the data bus. If the pointer address was not mapped to a data cache address, the pointer to the next emulation routine is output to the data bus at the data outputs of the memory. The present invention also includes a method for manufacturing an address selective address mapping system.