NEC Direction T-Series, Руководство пользователя

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Technical Information 1-3
Chipset
The Intel 82430TX PCI chipset provides DMA, memory, bus, and cache control. The
chipset includes the following chips:
„
430TX System Controller (MTXC)

integrates the cache, main memory DRAM
control and provides bus control to handle transfers between the processor, cache,
main memory, and PCI bus.
„
430TX PCI ISA IDE Xcelerator (PIIX4)

features multifunction PCI to ISA
bridge/USB support.
PCI Local Bus
The 32-bit industry-standard PCI bus is a highly-integrated input/output (I/O) interface that
offers the highest performance local bus available for the Pentium processor. The PCI bus
supports burst modes that send large chunks of data across the bus, allowing fast displays of
high-resolution images.
The high-bandwidth PCI local bus eliminates data bottlenecks found in traditional systems,
maintains maximum performance at high clock speeds, and provides a clear upgrade path to
future technologies.
The PCI bus contains two embedded PCI devices: the PCI local bus IDE interface and the
PCI video/graphics controller. The PCI bus also contains a connector for attaching the bus
expansion board.
Expansion Bus
The expansion bus contains two ISA slots, three PCI slots, and one PCI/ISA slot. The PCI
ISA IDE Xcelerator chip (430TX) provides the logic that enables the ISA bus functions.
With 24-bit memory addressing, a 16-bit data path, and an eight MHz clock, the ISA bus is
designed to support all peripherals compatible with the IBM

AT
™
standard. For PCI
functions, the Xcelerator chip provides 32-bit memory addressing, 32-bit data path, and a
33 MHz clock speed.
BIOS
The BIOS (Basic Input Output System) is stored in the Intel U6520222D Flash EPROM.
The Flash EPROM is reprogrammable and allows fast, economical BIOS upgrades.
The system memory map in shown in Table 1-2.