APPENDIX A: Resource Allocation
Default IRQ |
PIR |
Function |
Alternative Mappings |
Device |
IRQ0 |
Timer | N/A | South Bridge |
|
IRQ1 |
Keyboard | N/A | South Bridge |
|
IRQ2 |
Internal 8259 Cascade | N/A | South Bridge |
|
IRQ3 |
X |
Modem | Model Specific | Modem |
IRQ4 |
X |
COM1 Serial Port | 3, Disabled | Super I/O |
IRQ5 |
X |
Audio | 7, 9, 10, 11, Disabled | Audio Controller |
IRQ6 |
X |
Floppy Disk Controller | Disabled | Super I/O |
IRQ7 |
X |
LPT1 Parallel Port | 3, 4, 5, 9, 10, Disabled | Super I/O |
IRQ8 |
Real Time Clock | N/A | South Bridge |
|
IRQ9 |
X |
USB, NIC | PIR | USB Controller |
IRQ10 |
X |
|||
IRQ11 |
X |
|||
IRQ12 |
X |
PS/2 Mouse | Disabled | South Bridge |
IRQ13 |
Numeric Coprocessor | Disabled | South Bridge |
|
IRQ14 |
X |
Primary IDE | PIR, Disabled | IDE Controller |
IRQ15 |
X |
Secondary IDE | PIR, Disabled | IDE Controller |
Default DMA |
Function |
Alternative Mapping |
Device |
DMA0 |
Audio Record |
1, 3, Disabled |
Audio Controller |
DMA1 |
Audio Playback |
0, 3, Disabled |
Audio Controller |
DMA2 |
Floppy Controller |
N/A |
Super I/O |
DMA3 |
ECP Printer Port |
0, 1, 2, Disabled |
Super I/O |
DMA4 |
Internal Cascade |
N/A |
South Bridge |
DMA5 |
Available |
South Bridge |
|
DMA6 |
Available |
South Bridge |
|
DMA7 |
Available |
South Bridge |
Address |
High I/O Address |
Function |
Alternative Mappings |
Device |
0000 |
000F |
DMA Controller #1 | South Bridge |
|
0010 |
001F |
DMA Controller Aliases | South Bridge |
|
0020 |
Interrupt Controller #1 Control Register | South Bridge |
||
0021 |
Interrupt Controller #1 Mask Register | South Bridge |
||
0022 |
003D |
Interrupt Controller Aliases | South Bridge |
|
0040 |
0043 |
Counter/Timer | South Bridge |
|
0044 |
004F |
Not used |
||
0050 |
0053 |
Counter/Timer Aliases | South Bridge |
|
0053 |
005F |
Not used |
||
0060 |
Keyboard Controller Data Register | South Bridge |
||
0061 |
Port B: SERR/IOCHK NMI, Speaker, Refresh | South Bridge |
||
0062 |
0063 |
Not used |
||
0064 |
Keyboard Controller Command/Status Register | South Bridge |
||
0065 |
006F |
Not Used |
||
0070 |
NMI Mask Register (Bit 7) | South Bridge |
||
0070 |
RTC/Configuration Memory Index Port (Bit 6:0) | South Bridge |
||
0071 |
RTC/Configuration Memory Data Port | South Bridge |
||
0072 |
RTC Extended Index | South Bridge |
||
0073 |
RTC Extended Data | South Bridge |
||
0074 |
007F |
Not Used |
||
0080 |
008F |
DMA Page Registers | South Bridge |
|
0090 |
0091 |
Alias of DMA page registers if SOUTH BRIDGE.4C.7=0 | South Bridge Not Used |
|
0092 |
Port 92 (fast reset and A20 gate) | South Bridge |
||
0093 |
009F |
Alias of DMA page registers if SOUTH BRIDGE.4C.7=0 | South Bridge Not used |
|
00A0 |
Interrupt Controller #2 Control Register | South Bridge |
||
00A1 |
Interrupt Controller #2 Mask Register | South Bridge |
||
00A2 |
00B1 |
Not Used |
||
00B2 |
APM Control | South Bridge |
||
00B3 |
APM Status | South Bridge |
||
00B4 |
00BF |
Not Used |
||
00C0 |
00DF |
DMA Controller #2 | South Bridge |
|
00E0 |
ESS Index Register | Audio |
||
00E1 |
ESS Data Register | Audio |
||
00E2 |
00E3 |
DDC2 Registers | ||
00E4 |
00E9 |
Not used |
||
00EA |
Ultra I/O Index Register | Super I/O |
||
00EB |
Ultra I/O Data Register | Super I/O |
||
00EC |
00EF |
Modem configuration | Modem |
|
00F0 |
00F1 |
Coprocessor Busy Clear/Reset | South Bridge |
|
00F2 |
00F8 |
Not Used |
||
00F9 |
Lock Configuration Register (Dummy Write) | Audio, Modem, Super I/O |
||
00FA |
Not used |
|||
00FB |
Unlock Configuration Register (Dummy Write) | Audio, Modem, Super I/O |
||
00FC |
TV/MPEG Configuration Register to remap base I/O address and interrupt resource | |||
00FD |
00FF |
Not Used |
||
0100 |
0101 |
Not Used |
||
0102 |
Video: POS. 102 register | Video |
||
0103 |
012F |
Not Used |
||
0130 |
0131 |
BGL Index/Data for second line modem See 260 for controllerless modems |
Modem |
|
0132 |
016F |
Not Used |
||
0170 |
0177 |
Secondary IDE Controller | South Bridge |
|
0178 |
01EF |
Not Used |
||
01F0 |
01F7 |
Primary IDE Controller | South Bridge |
|
01F8 |
0200 |
Not Used |
||
0201 |
Joystick Port | 200,202,203 |
Audio |
|
0202 |
021F |
Not Used |
||
0220 |
022F |
Audio Controller | 0230-023F, 0240-024F, 0250-025F |
Audio |
0230 |
025F |
Not Used |
||
0260 |
0263 |
Reserved-Modem use during POST | ||
0264 |
0277 |
Not Used |
||
0278 |
027F |
Reserved-Parallel Port | 0378 |
Super I/O |
0280 |
02E7 |
Not Used |
||
02E8 |
02EF |
Reserved-Serial Port (COM4) | 03F8 |
Super I/O |
02F0 |
02F7 |
Not Used |
||
02F8 |
02FF |
FAX/Modem (COM2) | 02E8-02EF, 03E8-03EF, 03F8-03FF |
Modem |
0330 |
0331 |
MPU-401 | 0300-0301 0310-0321 0320-0321 disabled |
Audio |
0332 |
036F |
Not Used |
||
0370 |
0377 |
Reserved-Floppy Drive Controller 2 | Super I/O |
|
0378 |
037F |
Parallel Port | 0278-27F 03BC-3BF |
Super I/O |
0380 |
0387 |
Not Used |
||
0388 |
038B |
Audio FM Synthesizer | Audio |
|
038C |
03B3 |
Not Used |
||
03B4 |
03B5 |
Video: Monochrome | Video |
|
03B6 |
03B9 |
Not Used |
||
03BA |
Video: Monochrome | Video |
||
03BB |
Not Used |
|||
03BC |
03BF |
Reserved-Parallel Port | Super I/O |
|
03C0 |
03CF |
Video: VGA Registers | Video |
|
03D0 |
03D3 |
Not Used |
||
03D4 |
03D5 |
Video: Color | Video |
|
03D6 |
03D9 |
Not Used |
||
03DA |
Video: Color | Video |
||
03DB |
03E7 |
Not Used |
||
03E8 |
03EF |
Reserved-Serial Port (COM3) | Super I/O |
|
03F0 |
03F7 |
Floppy Disk Controller (Primary) | Super I/O |
|
03F6 |
03F7 |
IDE Interface (Fixed Disk and CDROM) | South Bridge |
|
03F8 |
03FF |
Serial Port (COM1) | Super I/O |
|
0400 |
04EF |
Not Used |
||
04D0 |
Interrupt Controller #1 Edge/Level Control | South Bridge |
||
04D1 |
Interrupt Controller #2 Edge/Level Control | South Bridge |
||
04D2 |
0677 |
Not Used |
||
0678 |
067A |
Parallel Port ECP Mode | Super I/O |
|
0778 |
077A |
Parallel Port ECP Mode | Super I/O |
|
0CF8 |
PCI Configuration Index (32-bit I/O only) | North Bridge |
||
0CF9 |
Reset Control | South Bridge |
||
0CFC |
PCI Configuration Data | North Bridge |
||
46E8 |
Video: Adapter Sleep | Video |
Size | Low Address | High Address | System Function |
640 KB | 00000000 | 0009FFFF | Base Memory |
128 KB | 000A0000 | 000BFFFF | Video RAM |
48 KB | 000C0000 | 000CBFFF | Video ROM |
16 KB | 000CC000 | 000CFFFF | Unused |
48 KB | 000D0000 | 000DBFFF | Unused |
16 KB | 000DC000 | 000DFFFF | Used |
64 KB | 000E0000 | 000EBFFF | Used |
64 KB | 000F0000 | 000FFFFF | System BIOS ROM shadow image |
15 MB | 00100000 | 00FFFFFF | Standard Extended Memory |
64 MB | 01000000 | 04FFFFFF | Rest of Extended Memory |
60 MB | 05000000 | 07FFFFFF | Unused |
512 KB | 08000000 | 0807FFFF | Standard Direct Video Memory |
512 KB | 08080000 | 080FFFFF | Optional Direct Video Memory |
1919 MB | 08100000 | 7FFFFFFF | Unused |
16 MB | 80000000 | 80FFFFFF | Memory mapped I/O devices |
~2000 MB | 81000000 | FDFDFFFF | Unused/System ROM aliases |
128 KB | FDFE0000 | FDFFFFFF | System ROM (alias) |
~32 MB | FE000000 | FFFDFFFF | Unused |
128 KB | FFFE0000 | FFFFFFFF | System BIOS ROM |