Table of Contents
Advertisement
LEVEL 6 MEGABUS
I
MULTIPLE DEVICE CONTROLLER
f - - - - T - - - r -
I
I
I
I
I
I
DEVICE·
I
PAC
I
PERIPHERAL
DEVICE
Figure 1-2. Peripheral Device Connection
commands or by operator entered data. If a
requested. device becomes unavailable to the
system (device turned off, device busy, device
malfunctioning, etc.) the software outputs an
error code. The error message corresponding to
the error code is described in the
Series 60 (Level
6) GCOS/BES Operators Guide
and indicates to
the operator exactly what action is required to
correct the situation. Section 2 of this text
discusses the central processor, and sections 3
through 10 discuss the available peripherals.
For the system to operate, all the power
supplies must be turned on. Additionally, the
Power
Distribution
Unit
and
the
optional
Memory Save and Autorestart must have power
applied.
The order for application of power to the
Level 6 system is as follows:
Power Distribution Unit
Central Processor
Memory Save and Autorestart
Peripherals
Power Distribution Unit
The Power Distribution Unit is located in the
base of the cabinet (bottom of the rack; see
Figure 1-3). The Power Distribution Unit ON/
OFF switch must be set to the ON position by
the operator. This action is taken before power is
applied to the Central Processor.
Memory Save and Autorestart
Memory
Save
and
Autorestart
(PSS91
°
1/9lO2) is an optional device which
INTRODUCTION
Figure 1-3. Power Distribution Unit
provides for the retention of up to 131,072 bytes
of memory for a two hour period in the event of
a power failure or fault (see Figure 1-4).
In the event of a normal system power down,
the memory contents are automatically retained
(with the ON/OFF switch positioned ON) until
the system is manually powered up again.
ON/OFF Switch
An ON/OFF switch enables the selection of
one of two states. When it is placed in the OFF
position, memory contents are not saved. When it
is placed in the ON position, however, the central
processor memory contents are saved for up to
two hours by the battery backup unit.
Memory On Indicator
The device also contains a Memory On indica
tor which when illuminated indicates that the
device is functioning properly. Loss of ac power
for longer than two hours or a malfunction in the
device (battery backup supply dead, etc.) causes
the power supply to be turned Off and the
Memory On indicator to be extinguished. Should
total device failure occur, information retained is
not available. Manual depression of the Reset
Button is necessary to re-illuminate the indicator
if the device itself lost power or the two hour
time period was exceeded. AC power must be
applied to the device and the battery, if run
down, requires time to be recharged.
Reset Button
Depression of the Reset button restores power
to the device, thereby enabling a restart.
1-2
AT04
Advertisement
Table of Contents
