Microprocessor with OEM mode for power management with input/output intiated selection of special address space
US5274791A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 5, 1991 |
| Grant date | Dec 28, 1993 |
| Priority date | — |
| Expiry date | Jul 5, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F1/3203
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention provides a microprocessor with a special OEM mode of operation that can be used by an OEM system integrator to implement special tasks such as power management. The OEM mode provided by the present invention is designed for use by a system integrator who integrates a microprocessor into a larger system such as a personal computer. The OEM mode of operation provided by this invention adds features to the overall system; however, it is transparent to system programmers. The system integrator can use the OEM mode to configure a system so that the system has certain special power management features, which can not be accessed by programmers who use the system. The OEM mode provided by the present invention is accessed by a signal on a special I-O pin. For example, an external timer can periodically provide signals to this special pin, thereby periodically interrupting the microprocessor and putting the microprocessor in the OEM mode. Special power management code stored in an external ROM can be executed each time the microprocessor is placed in OEM mode. At the end of the operations performed in OEM mode, the microprocessor is restored to the state where the OEM …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.