ID protected memory with a maskable ID template
US4903299A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1988 |
| Grant date | Feb 20, 1990 |
| Priority date | — |
| Expiry date | Jun 28, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/1466
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A remotely disposed RAM (12) is provided which is accessible by a centralized serial CPU (28) through a common data link. The RAM (12l ) is interfaced with the common data link through a serial port (19) and access thereto is controlled by an arbiter (10). The arbiter (10) includes a protocol shift register (31) for receiving control information, ID information and address information for the RAM (12). The ID information is compared with prestored identification information in an ID template (37). This ID template is operable to have a portion thereof masked off in response to receiving a mask command as part of the control information. If a match is present between the unmasked portion of the ID template and the corresponding portion of the ID information, access is allowed to the arbiter (10) and the RAM (12). A response is then transmitted to the common data link in the form of data read from the RAM.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.