NEC PowerMate 2000 Series, Инструкция по обслуживанию и справочник, Страница: 101 / 175

System Board 4-9
System Board Components
Component Function
CardBus Controller (TI PCI1420) High performance PCI-to-CardBus controller supporting two
independent PC card sockets
32-bit transfers at 33 MHz
Supports any combination of 16-bit and 32-bit CardBus PC
cards, powered by 5V or 3.3V (see “Advanced Menu” in Section
2 to select the voltage).
Internally buffered to allow PC card hot insertion and removal
without external buffering.
Sound Intel 82801AB (ICHO) with AD1881 chip
PCM 8/16 bit stereo record/playback, sampling rate 8.0 to 48.0
KHz, compatible with Windows Sound System
Processor and Secondary Cache
The system uses an Intel Celeron processor with an internal clock speed of 433
MHz.
The processor is an advanced pipelined 32-bit addressing, 64-bit data processor
designed to optimize multitasking operating systems. The 64-bit registers and
data paths support 64-bit addresses and data types.
To use the processor’s power, the system features an optimized 64-bit memory
interface and 128 KB of secondary write-back cache on the processor.
The processor is compatible with 8-, 16-, and 32-bit software written for the
Intel386™, Intel486™, Pentium, and Pentium Pro processors. The processor is
mounted in a Socket370 connector. A heat sink is attached to the top of the
processor for cooling.
System BIOS
The PCI-compatible BIOS is contained in a flash memory device on the system
board. The BIOS provides the Power-On Self-Test (POST), the system Setup
program, a PCI and IDE auto-configuration utility, and BIOS recovery code.
The system BIOS is always shadowed. Shadowing allows any BIOS routine to
be executed from fast 32-bit DRAM on the system board, instead of from the
slower 8-bit flash device.
The Flash ROM allows fast, economical BIOS upgrades. The Flash ROM is a
reprogrammable EPROM containing both the system and video BIOS. Using
the Flash ROM to change the ROM BIOS provides the following advantages:
!
the BIOS upgrade is performed quickly and easily
!
the expense of replacing ROM BIOS chips is eliminated, so system
maintenance costs are reduced