System Memory Map - NEC POWERMATE ENTERPRISE NETPC Service Manual

The BIOS programs execute the Power-On Self-Test, initialize processor controllers, and
interact with the display, diskette drives, hard disk drives, communication devices, and
peripherals. The system BIOS also contains the Setup utility. The POST 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 having to physically remove 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.
Memory Space
100000-10000000
F0000-FFFFF
EC000-EFFFF
EA000-EBFFF
E9000-E9FFF
E8000-E8FFF
E4000-E7FFF
E0000-E3FFF
C8000-D7FFF
A0000-C7FFF
9F800-9FFFF
80000-9F7FF
00000-7FFFF
Table 1-3 System Memory Map
Size Function
256 MB Extended memory
64 KB PTL system BIOS
16 KB Reserved for BIOS
8 KB ECSD (Plug and Play configuration and DMI)
4 KB Reserved for BIOS
4 KB OEM logo or Scan User Flash
32 KB Reserved for BIOS (currently available as UMB)
96 KB USB buffer area
160 KB Available HI DOS memory (open to ISA and PCI bus)
1 KB Video memory and BIOS
127 KB Extended BIOS data (moveable by memory manager
software)
126 KB Extended conventional memory
512 KB Conventional memory
Technical Information 1-9