| 摘要 |
<p>The present invention provides a microprocessor (20) with a special OEM mode of operation transparent to system programmers, 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 accessed by a signal on a special I-O pin (21F). For example, an external timer (26) can periodically provide signals to this special pin (21F), thereby periodically interrupting the microprocessor (20) and putting the microprocessor (20) in the OEM mode. Special power management code stored in an external ROM (25A) can be executed each time the microprocessor (20) is placed in OEM mode. At the end of the operations performed in OEM mode, the microprocessor (20) is restored to the state where the OEM mode of operation began.</p> |
