Chapter 3
Hardware
22
Reference Manual
ReadyBoard 910
Memory Map
The following table provides the common PC/AT memory allocations. These are DOS-level addresses. The
OS typically hides these physical addresses by way of memory management. Memory below 000500h is
used by the BIOS.
I/O Address Map
shows the I/O address map. These are DOS-level addresses. The OS typically hides these physical
addresses by way of memory management.
Table 3-2. Memory Map
Base Address
Function
00000000h - 0009FFFFh
Conventional Memory
000A0000h - 000AFFFFh
Graphics Memory
000B0000h -
000B7FFFh
Mono Text Memory
000B8000h -
000BFFFFh
Color Text Memory
000C0000h -
000CFFFFh
Standard Video BIOS
000D0000h - 000DFFFFh
Reserved for Extended BIOS
000E0000h - 000EFFFFh
Extended System BIOS Area
000F0000h -
000FFFFFh
System BIOS Area (Storage and RAM Shadowing)
Top 32, 64, or 128MB of
Physical Memory
Shared memory of Integrated Graphics enabled
FFF80000h -
FFFFFFFFh
System Flash
Table 3-3. I/O Address Map
Address (hex)
Subsystem
0000-000F
Primary DMA Controller
0020-0021
Master Interrupt Controller
0040-0043
Programmable Interrupt Timer (Clock/Timer)
0060
Keyboard Controller
0061
NMI, Speaker control
0063
NMI Controller
0064
Keyboard Controller
0065
NMI Controller
0067
NMI Controller
0070-007F
CMOS RAM, NMI Mask Reg, RT Clock
0080
System reserved
0081-0083
DMA Page Registers
0084-0086
System reserved
0087
DMA Page Register
0088
System reserved
0089-008B
DMA Page Registers
008C-008E
System reserved
008F
DMA Page Register