NEC NEC Express5800 Series, Online Service Manual

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System Cabling A-3
Standard Configuration
Your system is cabled using a dual channel on-board IDE Controller and an on-board Symbios
Logic SYM53C875 SCSI Controller. The on-board IDE controller supports the internally mounted
CD-ROM as its first (master) device and an optional IDE device as its second (slave) device. The
SCSI controller attaches to a 68-pin 16-bit (wide) SCSI connector interface and is capable of
supporting a maximum of four 1-inch high SCSI hard disk drives or three 1.6-inch high SCSI hard
disk drives. Also, a 3.5-inch diskette drive is installed in all systems and interfaces separately to the
system board.
Referring to the "IDE Disk System Cable Configuration" Figure, your system can be cabled using
the on-board dual enhanced IDE controller. This controller has two connectors (primary and
secondary) on the system board, each connector supporting a first (master) and a second (slave)
device. This provides support for the internally mounted IDE CD-ROM, an optional tape, and up
to three internally mounted IDE hard disk drives. An IDE cable (K) connects the secondary IDE
connector to the CD-ROM as its master device (I) and an optional IDE device as its slave device (J).
Another IDE cable (O) connects the primary IDE connector to the optional first hard drive (HD1) as
its master device (M) and the optional second hard drive (HD2) as its slave device (N).
As an option, the on-board SCSI controller can be used to control a SCSI tape drive. In this case, a
SCSI cable (D) connects the wide SCSI connector to the optional SCSI tape drive (B) via a narrow
SCSI to wide SCSI adapter (C). The tape drive SCSI address assignment is 2. SCSI termination must
be installed in the last SCSI drive of the daisy chain cabling. Since the tape is the only SCSI device,
the termination resistors (A) are installed in the tape drive.
When adding or removing IDE devices, consider the following:
n The system board supports a primary and secondary IDE channel connector. Each of these
supports two devices, for a total of four IDE devices.
n A first (master) device and a second (slave) device are supported on both the primary and
secondary IDE channel connector.
n The device configuration, master versus slave, is determined by jumpers on the devices. Cable
Sense (CS) device configuration is not supported.
n
If only one device is on a channel connector it must be set as the master device.