Pci Interrupt Request Routing - MSI KM4M Series Manual

PCI Interrupt Request Routing

The IRQ, acronym of interrupt request line and pronounced I-R-Q, are
hardware lines over which devices can send interrupt signals to the
microprocessor.
The PCI IRQ pins are typically connected to the PCI bus INT A# ~ INT
D# pins as follows:
PCI Slot 1
PCI Slot 2
PCI Slot 3
Order 1 Order 2
INT A# INT B#
INT B# INT C#
INT C# INT D#
Hardware Setup
Order 3 Order 4
INT C# INT D#
INT D# INT A#
INT A# INT B#
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