HP Vectra VL400 User Manual
Page 47
47
4 BIOS Overview
BIOS Addresses
Although the Setup program can be used to change some of the settings, the
following address map is not completely BIOS dependent, but is determined
partly by the operating system. Note that some of the I/O addresses are
allocated dynamically.
I/O Address Ports
Function
0000 - 000F
DMA controller 1
0020 - 0021
Master interrupt controller (8259)
002E - 002F
NS364 Configuration registers
0040 - 0043
Timer 1
0060, 0064
Keyboard controller (reset, slow A20)
0061
Port B (speaker, NMI status and control)
0070
Bit 7: NMI mask register
0070 - 0071
RTC and CMOS data
0080
Manufacturing port (POST card)
0081 - 0083, 008F
DMA low page register
0092
PS/2 reset and Fast A20
00A0 - 00A1
Slave interrupt controller
00C0 - 00DF
DMA controller 2
00F0 - 00FF
Co-processor error
0170 - 0177
IDE secondary channel
01F0 - 01F7
IDE primary channel
0278 - 027F
LPT 2
02E8 - 02EF
Serial port 4 (COM4)
02F8 - 02FF
Serial port 2 (COM2)
0372 - 0377
IDE secondary channel, secondary floppy disk drive
0378 - 037A
LPT1
03B0 - 03DF
VGA
03E8 - 03EF
COM3
03F0h- 03F5
Floppy disk drive controller
03F6
IDE primary channel
03F7
Floppy disk drive controller
03F8 - 03FF
COM1
04D0 - 04D1
Interrupt edge/level control
0678 - 067B
LPT2 ECP
0778 - 077B
LPT1 ECP
0CF8 - 0CFF
PCI configuration space