NEC NEC Express5800 Series, Онлайн руководство по обслуживанию

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1-8 System Overview
The system board has four full-length PCI connectors. One of the connectors shares a chassis
expansion slot with an ISA connector. PCI features:
n Bus speed up to 33 MHz
n 32-bit memory addressing
n 5 V signaling environment
n Burst transfers of up to 133 Mbps
n 8-, 16-, or 32-bit data transfers
n Plug and Play ready
n Parity enabled.
Real-Time Clock/Calendar
The real-time clock provides system clock/calendar information stored in a non-volatile memory
(NVRAM). The real-time clock battery provides power backup for the real-time clock.
BIOS
A BIOS and Setup Utility are located in the Flash EPROM on the system board and include support
for system setup and PCI/ISA Plug-and-Play auto-configuration. A number of security, reliability,
and management features also have been incorporated to meet vital server needs.
IDE Controller
The system includes a dual channel enhanced IDE interface controller. The controller has a
primary and secondary connector located on the system board, each connector supporting a master
and a slave device. The IDE controller provides support for the internally mounted standard CD-
ROM, an optional tape drive, and up to three optional hard disk drives for a total of four IDE
devices.
SCSI Controller
The system includes a Symbios Logic SYM53C875 single channel PCI SCSI controller. The
controller is capable of operations using either 8 or 16 bit SCSI providing 10 MB/s (Fast-10) or
20 MB/s (Fast-20) throughput, or 20 MB/s (Ultra) or 40 MB/s (Ultra-wide). As implemented, the
controller attaches to a 68 pin 16 bit (wide) SCSI connector interface. As a PCI bus master the
SYM53C875 supports burst data transfers on PCI up to the maximum rate of 132 MB/sec using
onchip buffers.
The SCSI controller provides support for optional SCSI devices including internally mounted tape
and/or up to four internally mounted hard disk drives. No logic, termination, or resistor loads are
required to connect devices to the SCSI controller other than termination at the end of the cable.
The SCSI bus is terminated on the system board with active terminators that cannot be disabled.
Network Controller
The system board includes a 10BASE-T/100BASE-TX network controller based on the Intel 82558
Fast Ethernet PCI Bus Controller. As a PCI bus master, the controller can burst data at up to
132 MB/sec. The controller contains two receive and transmit FIFO buffers that prevent data
overruns or underruns while waiting for access to the PCI bus. The controller has the following:
n 32-bit PCI bus master interface (direct drive of bus), compatible with
PCI Bus Specification,
Revision 2.1
n Chained memory structure with improved dynamic transmit chaining for enhanced
performance
n Programmable transmit threshold for improved bus utilization
n Early receive interrupt for concurrent processing of receive data
n On-chip counters for network management
n Autodetect and autoswitching for 10 or 100 Mbps network speeds