Technical Reference
39
2.3 Fixed I/O Map
Table 11. I/O Map
Address (hex)
Size
Description
0000 - 00FF
256 bytes
Used by the Desktop Board D102GGC2. Refer to the
IXP 450 data sheet for dynamic addressing information.
0170 - 0177
8 bytes
Secondary Parallel ATA IDE channel command block
01F0 - 01F7
8 bytes
Primary Parallel ATA IDE channel command block
0228 - 022F
(Note 1)
8
bytes
LPT3
0278 - 027F
(Note 1)
8
bytes
LPT2
02E8 - 02EF
(Note 1)
8
bytes
COM4
02F8 - 02FF
(Note 1)
8
bytes
COM2
0374 - 0377
4 bytes
Secondary Parallel ATA IDE channel control block
0377, bits 6:0
7 bits
Secondary IDE channel status port
0378 - 037F
8 bytes
LPT1
03E8 - 03EF
8 bytes
COM3
03F0 - 03F5
6 bytes
Diskette channel
03F6 – 03F7
1 byte
Primary Parallel ATA IDE channel control block
03F8 - 03FF
8 bytes
COM1
04D0 - 04D1
2 bytes
Edge/level triggered PIC
LPTn + 400
8 bytes
ECP port, LPTn base a 400h
0CF8 - 0CFB
(Note 2)
4 bytes
PCI Conventional bus configuration address register
0CF9
(Note 3)
1 byte
Reset control register
0CFC - 0CFF
4 bytes
PCI Conventional bus configuration data register
FB00 – FB07
8 bytes
Primary Parallel ATA IDE bus master registers
FB08 – FB0F
8 bytes
Secondary Parallel ATA IDE bus master registers
Notes:
1.
Default, but can be changed to another address range
2.
Dword access only
3.
Byte access only
NOTE
Some additional I/O addresses are not available due to IXP 450 address aliasing. The IXP 450
data sheet provides more information on address aliasing.