52
Appendix-A I/O Port Address Map
Each peripheral device in the system is assigned a set of I/O port addresses which also becomes the identity of the
device. The following table lists the I/O port addresses used.
Address
Device Description
000h - 01Fh
DMA Controller #1
020h - 03Fh
Interrupt Controller #1
040h - 05Fh
Timer
060h - 06Fh
Keyboard Controller
070h - 07Fh
Real Time Clock, NMI
080h - 09Fh
DMA Page Register
0A0h - 0BFh
Interrupt Controller #2
0C0h - 0DFh
DMA Controller #2
0F0h
Clear Math Coprocessor Busy Signal
0F1h
Reset Math Coprocessor
1F0h - 1F7h
IDE Interface
2F8h - 2FFh
Serial Port #2(COM2)
2B0h- 2DFh
Graphics adapter Controller
360h - 36Fh
Network Ports
3F8h - 3FFh
Serial Port #1(COM1)
Appendix-B Interrupt Request Lines (IRQ)
Peripheral devices use interrupt request lines to notify CPU for the service required. The following table shows the
IRQ used by the devices on board.
Level
Function
IRQ0
System Timer Output
IRQ1 Keyboard
IRQ3
Serial Port #2
IRQ4
Serial Port #1
IRQ8
Real Time Clock
IRQ14 Primary
IDE
IRQ15 Secondary
IDE
