Intel Desktop Board D975XBX2 Technical Product Specification 
52   
2.3  Fixed I/O Map 
Table 12. I/O Map 
Address (hex)  Size  Description 
0000 - 00FF  256 bytes  Used by the Desktop Board D975XBX2.  Refer to the  
ICH7-R/ICH7-DH 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  
03F4 â 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 address + 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 
FFA0 - FFA7  8 bytes  Primary Parallel ATA IDE bus master registers 
FFA8 - FFAF  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. 
î NOTE 
Some additional I/O addresses are not available due to ICH7-R/ICH7-DH address 
aliasing.  The ICH7-R/ICH7-DH data sheet provides more information on address 
aliasing. 
For information about  Refer to 
Obtaining the ICH7-R/ICH7-DH data sheet   Section 1.2 on page 17