User`s guide

SHOW OTHER_CONTROLLER command to check the status of your
batteries.
See Section 4.10 for information on how to upgrade your cache module option
from a read to write-back cache module (or from 16-MB to 32-MB write-back
cache module).
The battery circuit automatically detects loss of backplane power and switches
from backplane +5V power to battery power. This transition occurs when the
backplane supply drops to approximately +4.65V +/- .05V, providing adequate
time to switch to the battery power before the supply voltage drops below +4.5V,
the minimum voltage for the write-back cache module DRAMS.
The battery charge circuit senses the battery voltage and automatically activates
the charger as needed to achieve and maintain full battery charge. The battery
charger is powered from the backplane +12V supply and a switch-mode topology
is used. Battery charge time from a fully discharged condition is 10 hours
maximum.
Minimum data retention time when operating from fully charged batteries is
estimated to be greater than 100 hours, based on an estimated total load of less
than 40 mA at +5V on the batteries. Digital supports data retention up to, but
not greater than 100 hours with fully charged batteries. You may lose your data
if you run on battery power for more than 100 hours.
If a power failure occurs, and the write-cache module batteries are used, when
the power is restored the firmware checks the status of the battery charge at 4
minute intervals.
2.1.7 Operator Control Panel
The operator control panel (OCP) LEDs reflect the state of the controller and
the external bus. The green OCP LED is reserved for controller status, and the
amber LEDs are reserved for the SCSI–2 port (bus) information. When a fault
condition occurs, the OCP LEDs indicate a fault code. If a controller has ceased
functioning, the green LED (reset) is lit continuously.
The controller can be reset/restarted (if needed) by pressing the reset (//) button
on the OCP.
The following sections briefly describe the physical appearance of the operator
control panels for HSJ30, HSJ40, HSD30, and HSZ array controllers.
2.1.7.1 HSJ40 and HSJ30 Array Controller OCP
Figure 2–2 shows the OCP on an HSJ40 array controller’s front bezel and the
location of the program card slot.
2–6 Controller Technical Description