5-20
Stinger® FS/Stinger FS+ Getting Started Guide
Configuring Control Modules and System Timing
Configuring system clocking
[in SYSTEM]
system-8k-clock = controller
Using the BITS clock source
The following commands cause the system to first attempt to use a BITS clock as its
clock source, and to use the built-in clock only if it does not find a valid BITS signal:
admin>
read system
SYSTEM read
admin>
set system-8k-clock = bits
admin>
write
SYSTEM written
Loss of BITS signal indications and fall-back
If the
system-8K-clock
parameter in the
system
profile is set to
bits
and the
system detects a loss of signal, it displays the following message:
LOG alert, Shelf 1, Controller-1, Time: 17:02:01--
BITS clock source has been lost - 8kHz clock is free running
If no other clock source is eligible, the system then displays the following message:
LOG notice, Shelf 1, Controller-1, Time: 17:02:01
Master clock source changed to local oscillator
When the Stinger unit recovers the BITS signal, it displays the following messages:
LOG alert, Shelf 1, Controller-1, Time: 17:02:03--
BITS clock source has been recovered - 8kHz clock is locked
LOG notice, Shelf 1, Controller-1, Time: 17:02:03--
Master clock source changed to T1 framer
Parameter
Setting
System-8K-Clock
Source for the master system clock.
With the default
controller
setting, the Stinger unit uses
the built-in 8kHz clock on the primary control module.
If set to
lim-or-
trunk-module
, the unit obtains its clock
signal from a trunk port that has been configured as an
eligible clock source, using the ports in order of their
priority. If no eligible trunk ports are available, it uses the
control module clock.
If set to
bits
, the unit sources its clock from the building
interoffice timing source (BITS) T1 framer on its alarm
relay.
If set to
ami-8k
, a model A-J control module sources the
400Hz ISDN reference clock used in Japan, from the BITS
input across the backplane for use by Annex C LIMs. (The
model A-J control module is available only for the Stinger
LS.)