Legacy Document

Inside Macintosh: Devices /

Chapter 6 - Power Manager / Power Manager Reference

Power Manager Dispatch Routines / Controlling the Processor

EnableProcessorCycling

You can use the EnableProcessorCycling function to turn the processor cycling feature on and off.

void EnableProcessorCycling(Boolean enable);

enable

A Boolean that specifies whether to enable processor cycling.

DESCRIPTION

The EnableProcessorCycling function enables processor cycling if a value of true is passed in, and disables it if false is passed.

WARNING

You should follow the advice of the mustProcessorCycle bit in the feature flags when turning processor cycling off. Turning processor cycling off when it's not recommended can result in hardware failures due to overheating.

ASSEMBLY-LANGUAGE INFORMATION

The trap is _PowerMgrDispatch ($A09E). The selector value for EnableProcessorCycling is 25 ($19) in the low word of register D0. The Boolean value to set is passed in the high word of register D0.

SEE ALSO

You can use the PMFeatures function (page 6-41) to determine whether the computer supports processor cycling.