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1-8 Technical Information
reduces inadvertent system board damage that can take place when replacing
ROMs
facilitates adopting new technology while maintaining corporate standards
gives network administrators company-wide control of BIOS revisions.
The BIOS programs execute the Power-On Self-Test, initialize processor controllers, and
interact with the display, diskette drives, hard disks, communication devices, and
peripherals. The system BIOS also contains the Setup utility. The hardware setup default
copies the ROM BIOS into RAM (shadowing) for maximum performance.
The Flash ROM allows the system and video BIOS to be upgraded with the BIOS Update
utility, without removing the ROM (see Section 2 for further information on the BIOS
Update utility). The Flash ROM supports the reprogramming of the system BIOS and the
video BIOS.
The system memory map is shown in Table 1-3.
Table 1-3 System Memory Map
Memory Space
Size
Function
100000-8000000
130048 KB
Extended memory (configurable/upgradable)
E0000-FFFFF
64 KB
AMI System BIOS
EC000-EFFFF
16 KB
FLASH boot block (available as UMB)
EA000-EBFFF
8 KB
ECSD (Plug and Play configuration area)
E9000-E9FFF
4 KB
Reserved for BIOS
E8000-E8FFF
4 KB
OEM logo (available as UMB)
E0000-E7FFF
32 KB
BIOS reserved (currently available as UMB)
C8000-DFFFF
96 KB
Available HI DOS memory (open to ISA and PCI
bus)
A0000-C7FFF
160 KB
Available HI DOS memory (normally reserved for
Video BIOS)
9FC00-9FFFF
1 KB
Extended BIOS data
80000-9FBFF
127 KB
Extended conventional memory
00000-7FFFF
512 KB
Conventional base memory
Summary of Contents for MT-2550-24874C
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