System Memory Map
Memory is mapped by the memory controller registers.
Figure 2-11 shows the memory map for a correctly functioning
system. Memory can be mapped differently if POST detects an error
in system board memory or RT/CMOS RAM. In the figure, the
variable
x
represents the number of 1-MB blocks of system board
memory starting at or above the hex 100000 boundary.
Figure 2-11. System Memory Map
Hex Address Range Function
00000000 to 0009FFFF 640-KB system board RAM
000A0000 to 000BFFFF Video RAM
000C0000 to 000C9FFF System board video BIOS ROM mapped to
RAM
000C8000 to 000EFFFF Channel ROM
000F0000 to 000FFFFF 64-KB system board ROM mapped to RAM
00100000 to (00100000 +
x
MB)
x
MB system board RAM
FFFF0000 to FFFFFFFF 64-KB system board ROM
(same as 000F0000 to 000FFFFF)
2-16 System Board
To Next Page
Loading...
