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4 Summary of the HP/Phoenix BIOS
HP/Phoenix BIOS (BIOS version: GX.07.xx)
BIOS I/O Port Map (BIOS version: GX.07.xx)
This section describes the HP BIOS port map. The next section provides
more details about how the BIOS uses the system board components
mentioned in the I/O port list.
I/O Address Ports
Function
Bits
0000-000F
DMA controller 1
8
0020-0021
Interrupt controller 1
8
0040-0043
Interval timer 1
8
0060, 0064
Keyboard controller
8
0061
NMI status and control
8
0070
NMI mask register, RTC address
8
0071
RTC data
8
0081-0083, 008F
DMA low page register
8
0092
Alternate reset and A20 Function
8
00A0-00A1
Interrupt controller 2
8
00C0-00DF
DMA controller 2
8
00F0-00FF
Co-processor error
0100-0109
HP reserved
015C-015D
I/O Controller
0170-0177
IDE controller secondary channel
01F0-01F7
IDE controller primary channel
0278-027F
Parallel port 3
02E8-02EF
Serial Port 4
02F8-02FF
Serial Port 2
0370-0375
Secondary floppy disk controller
0376
IDE controller secondary channel
0377
Secondary floppy disk controller