Microprocessor with repeat instruction
US4713749A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 12, 1985 |
| Grant date | Dec 15, 1987 |
| Priority date | — |
| Expiry date | Feb 12, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/30167
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A system for real-time digital signal processing employs a single-chip microcomputer device having separate on-chip program and data memory, with separate address and data paths for program and data. An external program address bus allows off-chip program fetch in an expansion mode, with the opcode returned by an external data bus. A bus interchange module allows transfer between the separate internal program and data busses in special circumstances. A multiplier circuit produces a single state multiply function separate from the ALU. One input to the ALU passes through a full-width shifter with sign extension. The on-chip program memory is a RAM which may be configured as either program or data memory space. The processor may operate will all off-chip program memory and a large on-chip data memory, or with program execution from on-chip RAM (downloaded from the off-chip program memory) using a block move instruction. A repeat instruction is used to save program space when using block-move, or when using multiply instructions as needed for digital filters or the like.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.