Abbreviated as APIC, an Advanced Programmable Interrupt Controller
is a PIC used to extend the number of
IRQs available, has more available
interrupt lines that a typical PIC and also supports distributed
CPUs. APIC must
be implemented on the motherboard and also supported by the
operating system. APIC differs from PIC as it offers multiple APICs on a motherboard connected via
a bus system. The CPU has a LOCAL APIC and the motherboard has at least one
I/O APIC.
A Description of the APIC I/O Subsystem The implementation of symmetric I/O in the FreeBSD SMP kernel is based upon the Intel Advanced Programmable Interrupt Controller (APIC).
The 8259 Programmable Interrupt Controller A technique is based on interrupts and allows a system to service devices on demand (asynchronously), thereby increasing the time available to perform other processing tasks.
