HP Vectra VL 5/xxx Series 5 User Manual
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4 Summary of the HP/Phoenix BIOS
BIOS Addresses
HP I/O Port Map (I/O Addresses Used by the System
1
)
Peripheral devices, accessory devices and system controllers are accessed
via the system I/O space, which is not located in system memory space. The
64 KB of addressable I/O space comprises 8-bit and 16-bit registers (called
I/O ports) located in the various system components. When installing an
accessory board, ensure that the I/O address space selected is in the free
area of the space reserved for accessory boards (100h to 3FFh).
The following address map is not BIOS dependent, but is determined by the
operating system. However, the Setup program can be used to change some
settings. Beware that some of the I/O addresses are allocated dynamically.
1.
If configured (legacy resources only).
I/O Address Ports
Function
0000h - 000Fh
DMA controller 1
0020h - 0021h
Interrupt controller 1
0040h - 0043h
Interval timer 1
0060h, 0064h
Keyboard controller
0061h
System speaker, or NMI status and control
0070h
NMI mask register, RTC and CMOS address
0071h
RTC and CMOS data
0081h - 0083h, 008Fh
DMA low page register
0092h
Alternate reset and A20 Function
00A0h - 00A1h
Interrupt controller 2
00C0h - 00DFh
DMA controller 2
00EAh - 00EBh
Internal port
00F0h - 00FFh
Co-processor error
0102h
Graphics controller (Matrox MGA)
0170h - 0177h
IDE hard disk drive controller secondary channel
01F0h - 01F7h
IDE hard disk drive controller primary channel
0200h - 0207h
Joystick port (Soundblaster)