AT&T DEFINITY 555-230-223 - Manual (Page 119)

Maintenance
Four main items make up the DEFINITY LAN Gateway system hardware
assembly shown in Figure 4-1. They are:
TN2208 Multi-Function Board (MFB) — The main circuit board that holds
the central processing unit, controllers, and memory devices that make
the system operational.
NOTE:
The DEFINITY LAN Gateway batteries are not field-replaceable. If
the batteries on the TN2208 are low, replace the the board.
TN2170 Alarm Board (ALB) — Works with the TN2208 to provide
monitoring for system power and environmental status, -48 VDC to +12
VDC power conversion for the mass-storage devices, and remote terminal
access. It also has the Ethernet interface.
3 1/2" Disk drive (ED-1E546-70 G8) — A hard disk used to store customer
data, boot the system, and log system error information.
3 1/2" Tape unit (part of ED-1E546-70 G1) — A 160-Mbyte data cassette
drive used to distribute software, store periodic backups of customer data,
install new software releases, and remove core dumps and other
maintenance information.
The system faceplate is made up of the following items:
Red Light-Emitting Diode (LED) — Indicates the health of the MFB and
Alarm Board. When flashing, it indicates a software problem. When it is
steadily lit, a hardware problem exists.
Liquid Crystal Display (LCD) — A 10-character alphanumeric display that
automatically shows the status of the MFB including alarms, and
information and procedures from a menu when any of the three buttons in
the following bullet item are pressed.
ENTER/YES, BACK, NEXT/NO buttons — Allow service personnel to
move through a structured menu system one item at a time as indicated
on the LCD.
BOOT/SHUTDOWN button — A recessed button used to take the entire
system off-line to a Maintenance Shutdown state. Closes all files, stops
file operations, and executes a spin-down of the disk drive. Pressing it
again when the system is shut down causes the system to reboot.
Cables include:
Interboard bus cable — A flat ribbon cable that provides the
communications link between the MFB and ALB. It transmits power,
environmental status, and control information.
Small Computer Systems Interface (SCSI) bus cables — Two
50-conductor ribbon cables that connect the disk and tape drives to the
ALB. They provide pass-through data transfer to the MFB.
Power cable — Provides 12 VDC power to the disk and tape drives from
the power module on the ALB.
Adapter cables — Two cables connected to the ALB and MFB through the
back of the switch. The MFB Y-cable provides administration/maintenance
terminal connections. The ALB cable provides an Ethernet connection to a
LAN, a reserved Amphenol connection, and an RS-232 connector to a
remote maintenance center via an external modem.
4-4 Issue 1 January 1996