Single shared ROM for storing keyboard microcontroller code portion and CPU code portion and disabling access to a portion while accessing to the other
US5603055A · kind A · utility
15Cited by
9References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1994 |
| Grant date | Feb 11, 1997 |
| Priority date | — |
| Expiry date | Jan 27, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/0638
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A shared keyboard and system ROM uses a single ROM for both the keyboard and the system operating system information (BIOS). The shared ROM is never simultaneously used for both of these functions. At initial boot-up, the system processor executes from the shared ROM to copy the system BIOS information to the system Random Access Memory DRAM. Once this copying has been completed, the shared ROM then is used by the keyboard subsystem. Different address ranges are employed in the shared ROM for the keyboard information and for the system BIOS.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.