BIOS Setup
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EC3-1816CLD2NA
APIC
Advanced programmable interrupt controller. Most motherboards above P4 level
support APIC and provide more than 16 interrupt sources, like IRQ16 - IRQ23; while
some others can have up to 28 interrupt sources, such as motherboard supporting
PCI-X. However, relevant OS are required to enable that function.
IO Port Address
Only 16 IO address lines are designed for X86, from 0 ~ 0FFFFh; there is 64K for the
system I/O address space. In traditional ISA connector, only the foregoing 1024 (0000
~ 03FFh) are adopted while the ports above 0400h are adopted by PCI and EISA
connectors. Each peripheral will occupy portion of the space. The table below shows
the I/O connectors used in X86 platform.
Address
Device Description
000h – 001Fh
DMA Controller#1
020h - 021h
Programmable Interrupt Controller
040h - 043h
System Timer
060h - 060h
Standard PS/2 Keyboard
064h – 064h
Standard PS/2 Keyboard
070h - 071h
System CMOS/Real Time Clock
081h - 091h
DMA Controller
0A0h – 0A1h
Programmable Interrupt Controller
0C0h – 0DFh
DMA Controller
0F0h – 0FFh
Numeric data processor
2E8h – 2EFh
COM4
2F8h – 2FFh
COM2
3B0h – 3BBh
Intel(R) Graphic Media Accelerator
3C0h – 3DFh
Intel(R) Graphic Media Accelerator
3E8h – 3EFh
COM3
3F8h – 3FFh
COM1
4D0h – 4D1h
Programmable Interrupt Controller
D00h – FFFFh
PCI Bus
