Dual port ram with arbitration status register
US4937781A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 13, 1988 |
| Grant date | Jun 26, 1990 |
| Priority date | — |
| Expiry date | May 13, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/18
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A dual port RAM includes an arbiter (10) which interfaces between a random access memory (12) and two ports, a serial port (19) and a parallel port (21). The arbiter (10) has an internal arbitration byte (38) for storing status information. The arbiter operates in first and second modes. In the first mode, the serial port (19) is afforded priority access to the system with status information stored in the arbitration byte (38). The parallel port (21) polls the arbitration byte (38) to determine the system status. In the second mode, the first port to attempt access is provided priority and this information is stored in the arbitration byte (38). In this mode, each port attempting access must poll the arbitration byte (38) before attempting access.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.