I/O Map
Table 31. I/O Map
Address (hex)
0000 - 000F
0020 - 0021
0040 - 0043
0060
0061
0064
0070 - 0071
0072 - 0073
0080 - 008F
0092
00A0 - 00A1
00B2 - 00B3
00C0 - 00DF
00F0
0170 - 0177
01F0 - 01F7
0228 - 022F*
0278 - 027F*
02E8 - 02EF*
02F8 - 02FF*
0376
0377, bits 6:0
0378 - 037F
03B0 - 03BB
03C0 - 03DF
03E8 - 03EF
03F0 - 03F5
03F6
03F8 - 03FF
04D0 - 04D1
LPTn + 400
0CF8 - 0CFB**
0CF9***
0CFC - 0CFF
FFA0 - FFA7
FFA8 - FFAF
Size
16bytes
2bytes
4bytes
1byte
1byte
1byte
2bytes
2bytes
16bytes
1byte
2bytes
2bytes
32bytes
1byte
8bytes
8bytes
8bytes
8bytes
8bytes
8bytes
1byte
7bits
8bytes
12bytes
32bytes
8bytes
6bytes
1byte
8bytes
2bytes
8bytes
4bytes
1byte
4bytes
8bytes
8bytes
Technical Reference
Description
DMA controller
Programmable Interrupt Control (PIC)
System timer
Keyboard controller byte— reset IRQ
System speaker
Keyboard controller, CMD / STAT byte
System CMOS / Real Time Clock
System CMOS
DMA controller
Fast A20 and PIC
PIC
APM control
DMA
Numeric data processor
Secondary IDE channel
Primary IDE channel
LPT3
LPT2
COM4 / video (8514A)
COM2
Secondary IDE channel command port
Secondary IDE channel status port
LPT1
Video (VGA)
Video (VGA)
COM3
Diskette channel 1
Primary IDE channel command port
COM1
Edge / level triggered PIC
ECP port, LPTn base address + 400h
PCI configuration address register
Turbo and reset control register
PCI configuration data register
Primary bus master IDE registers
Secondary bus master IDE registers
continued
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