Patent · US Expired

Microprocessor with non-aligned circular addressing

US6453405B1 · kind B1 · utility

19Cited by
15References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 31, 2000
Grant dateSep 17, 2002
Priority date
Expiry dateApr 17, 2021

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/3885
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A data processing system having a central processing unit (CPU) with address generation circuitry for accessing a circular buffer region in a non-aligned manner is provided. The CPU has an instruction set architecture that is optimized for intensive numeric algorithm processing. The CPU has dual load/store units connected to dual memory ports of a memory controller. The CPU can execute two aligned data transfers each having a length of one byte, two bytes, four bytes, or eight bytes in parallel by executing two load/store instructions. The CPU can also execute a single non-aligned data transfer having a length of four bytes or eight bytes by executing a non-aligned load/store instruction that utilizes both memory ports. A data transfer address for each load/store instruction is formed by fetching the instruction (600), decoding the instruction (610) to determine instruction type, transfer data size, addressing mode and scaling selection. For a non-aligned instruction, after selectively scaling (620) an offset provided by the instruction and combining the selectively scaled offset with a base address value the resultant address is then augmented (640) by a line size associated with …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.