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Chapter 1
Memory Address Map
Memory Address
Size
Function
000E0000h-000FFFFFh
128KB
System BIOS
000C0000h-000CFFFFh
64KB
VGA BIOS
000A0000h-000BFFFFh
128KB
Video memory (VRAM)
00000000h-0009FFFFh
640KB
Conventional memory
I/O Address Map
I/O Address
Function
0000-001F
Direct memory access controller
0000-0CF7
PCI bus
0010-001F
Motherboard resources
0020-0021
Programmable interrupt controller
0024-0025
Motherboard resources
0028-0029
Motherboard resources
002C-002D
Motherboard resources
002E-002F
Motherboard resources
0030-0031
Motherboard resources
0034-0035
Motherboard resources
0038-0039
Motherboard resources
003C-003D
Motherboard resources
0040-0043
System timer
004C-004F
Motherboard resources
0050-0053
Motherboard resources
0060-0060
Standard 101/102-Key or Microsoft Natural PS/2 Keyboard
0061-0061
System speaker
0062-0062
Microsoft ACPI-Compliant Embedded Controller
0064-0064
Standard 101/102-Key or Microsoft Natural PS/2 Keyboard
0066-0066
Microsoft ACPI-Compliant Embedded Controller
0070-0071
System CMOS/real time clock
0072-0077
Motherboard resources
0080-0080
Motherboard resources
0081-008F
Direct memory access controller
0090-009F
Motherboard resources
00A0-00A1
Programmable interrupt controller
00A4-00A5
Motherboard resources
00A8-00A9
Motherboard resources
00AC-00AD
Motherboard resources
00B0-00B5
Motherboard resources
00B8-00B9
Motherboard resources
00BC-00BD
Motherboard resources
00C0-00DF
Direct memory access controller
00F0-00FE
Numeric data processor
0170-0177
Secondary IDE Channel