Intel® 800 Series Chipset Family Platform Controller Hub (PCH)

Datasheet, Volume 1 of 2

ID Date Version Classification
833778 01/07/2025 Public
Document Table of Contents

ISH Interrupt Handling via IOAPIC (Interrupt Controller)

The legacy IOAPIC is the interrupt controller for the ISH. It collects inputs from various internal blocks and sends interrupt messages to the ISH controller. When there is a change on one of its inputs, the IOAPIC sends an interrupt message to the ISH controller.

The IOAPIC allows each interrupt input to be active high or active low and edge or level triggered.