User guide

Chapter 5 - VMS Services 5-15
ViperView—Monitor and Control
Unlock Alarm Masks
InBand modem device Mask Unlock Alarm flags mask and set park states
every time the modem registers with the VMS. These flags simplify and reduce
the device item-by-item settings, making them persistent during active state.
These flag settings are typically set on modems that are switched expansion
units or hub burst demodulators. If these devices are not masked, the unit will
generate many unwanted alarms in the system during normal operations.
Hub burst demodulators, when masked, only shutdown their link status alarms
that are typically part of the carrier lock/unlock, leaving all other internal alarms
unmasked.
The hub and remote expansion demodulator carrier alarm mask is cleared each
time it is switched to receive a return carrier from a remote. This unmasking of
alarms remains until the demodulator is returned to a parked state (unlock),
where it is re-masked to prevent unwanted network alarms.
If the modem is rebooted, the alarm masks are cleared until the next VMS regis-
tration.
Note: It is not necessary to mask the SLM-5650A hub burst demodulator. If the
alarm mask is set for this device type, the front panel carrier lock LED’s
WILL NOT illuminate.
The Unlock Alarm mask for a device is set from the Properties dialog.
For a CDM-570/570L or a CDD-56X, open the Properties window for the unit
,
as shown in figure 5-20.
For an SLM-5650A, open the Properties window for the demodulator
.
Table 5-2 Alarm Masking in a Typical Network
Device Type
Demodulator
Lock Status
Demodulator
Level Alarm
Demodulator
Auto Gain Ctrl
TDM/ Burst Cont. X X X
Remote
Hub Expansion X X X
Remote Expansion X X X
NOTE