Compaq Deskpro 4000N Technical Reference Manual page 63

SMI- Generation
The SMI- (System Management Interrupt) is typically used for power management functions.
When power management is enabled, inactivity timers are monitored. When a timer times out,
SMI- is asserted and invokes the microprocessor's SMI handler. The SMI- handler works with
the APM BIOS to service the SMI- according to the cause of the timeout.
Although the SMI- is primarily used for power managment the interrupt is also employed for the
QuickLock/QuickBlank functions as well.
Compaq Deskpro 4000N and 4000S Personal Computers
First Edition - September1997
Technical Reference Guide
4-21