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3 Motherboard BIOS and Setup Utility

3.1 Introduction

The motherboard uses an Intel BIOS, which is stored in Flash EEPROM and upgraded using a
floppy disk-based program. In addition to the Intel BIOS, the Flash EEPROM also contains the
Setup utility, Power-On Self Tests (POST), APM 1.1, the PCI auto-configuration utility, and
Windows 95 ready Plug and Play. This motherboard also supports system BIOS shadowing,
allowing the BIOS to execute from 64-bit on-board write-protected DRAM.
Hardware has been added to the board so only Intel compiled BIOS can be flashed into the Flash
EEPROM. This was done for extended virus protection.
The BIOS displays a sign-on message during POST identifying the type of BIOS and a five-digit
revision code. The initial production BIOS in the motherboard will be identified as 1.00.0x.CY0.
Information on BIOS functions can be found in the IBM† PS/2 and Personal Computer BIOS
Technical Reference published by IBM, and the ISA and EISA Hi-Flex AMIBIOS Technical
Reference published by AMI. Both manuals are available at most technical bookstores

3.2 BIOS Flash Memory Organization

The Intel PA28FB100BX 1 Mb Flash component is organized as 128K x 8 (128 KB). The Flash
device is divided into four areas, as described in Table 11.
Table 11. Flash Memory Organization
System Address FLASH Memory Area
FFFFE000H FFFFFFFFH 8 KB Boot Block (erasable only if jumpered)
FFFFD000H FFFFDFFFH 4 KB Plug and Play ESCD Storage Area
FFFFC000H FFFFCFFFH 4 KB Custom LOGO and Vital Product Data
FFFE0000H FFFFBFFFH 112 KB System BIOS Reserved during boot