User's Manual

10-32 Vol. 3
ADVANCED PROGRAMMABLE INTERRUPT CONTROLLER (APIC)
The setup information that can be specified in the registers of the LVT table is as
follows:
Vector Interrupt vector number.
Delivery Mode Specifies the type of interrupt to be sent to the processor. Some
delivery modes will only operate as intended when used in
conjunction with a specific trigger mode. The allowable delivery
modes are as follows:
000 (Fixed) Delivers the interrupt specified in the vector
field.
010 (SMI) Delivers an SMI interrupt to the processor
core through the processor’s local SMI signal
path. When using this delivery mode, the
vector field should be set to 00H for future
compatibility.
100 (NMI) Delivers an NMI interrupt to the processor.
The vector information is ignored.
101 (INIT) Delivers an INIT request to the processor
core, which causes the processor to perform
an INIT. When using this delivery mode, the
vector field should be set to 00H for future
compatibility.
111 (ExtINT) Causes the processor to respond to the in-
terrupt as if the interrupt originated in an
externally connected (8259A-compatible)
interrupt controller. A special INTA bus cycle
corresponding to ExtINT, is routed to the ex
-
ternal controller. The external controller is
expected to supply the vector information.
The APIC architecture supports only one Ex
-
tINT source in a system, usually contained in
the compatibility bridge.
Delivery Status (Read Only)
Indicates the interrupt delivery status, as follows:
0 (Idle) There is currently no activity for this inter-
rupt source, or the previous interrupt from
this source was delivered to the processor
core and accepted.
1 (Send Pending)
Indicates that an interrupt from this source
has been delivered to the processor core,
but has not yet been accepted (see
Section
10.6.5, “Local Interrupt Acceptance”).