AOpen AP43, User Manual

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Features
1-4
User’s Guide
System Board Parts
Microprocessor
The AP43 system board supports the Intel SL-enhanced, Intel
486SX/DX/DX2/DX4, AMD 486DX/DX2/DX4/DX4-S/Am5x86, Cyrix
Cx486DX/DX2/DX4/5X86 and TI 486DX2/DX4 series
microprocessors. Chapter 2 tells how to upgrade the processor.
ASICs
The two ASICs onboard are the SiS85C496 and SiS85C497. The
SiS85C496 acts as the PCI and CPU memory controller (PCM). It
integrates the host bridge, the cache and main memory DRAM
controller, the PCI bridge, the built-in IDE controller and the Fast Slow
Link (FS-Link) bus.
The SiS85C497 is the AT-bus controller and megacell (ATM)
component that acts as an interface the PCI/CPU/memory bus and
the ISA bus.
AMI BIOS
The AMI BIOS (basic input-output system) resides in the flash ROM
chip. This contains the program that performs the power-on self-tests
(POST) upon booting. During POST, this program activates the
peripheral devices, tests onboard memory, and prepares the system
for operation. Chapter 3 gives more information on the AMI BIOS.