Physical Description; Faceplate Leds - Nortel Enterprise 1000 Reference Manual

Page 28 of 236 NTAK20 clock controller daughterboard

Physical description

Faceplate LEDs

Table 4

Faceplate LEDs

State
On (Red)
On (Green)
Flashing (Green)
Off
553-3023-211 Standard 1.00 June 2001
stage. The green LED flashes until the clock controller is locked on to the
reference again.
If the incoming reference is unstable, the internal clock controller
continuously tracks, and the LED continuously flashes green. This condition
does not present a problem. It shows that the clock controller is continually
attempting to lock onto the signal. If slips are occurring, it means that there is
a problem with the clock controller or the incoming line.
Free-run (non-tracking)
In free-run mode, the clock controller does not synchronize on any outside
source. Instead, it provides its own internal clock to the system. This mode
can be used when the Succession CSE 1000 is used as a master clock source
for other systems in the network. Free-run mode is undesirable if the
Succession CSE 1000 is intended to be a slave to an external network
Free-run mode can occur when both the primary and secondary clock sources
are lost due to hardware faults or if invoked using software commands.
Each of the motherboards have five DTI/PRI LEDs and one clock controller
LED. The clock controller LED is dual-color (red and green). The clock
controller LED states are described in Table 4.
NTAK20 is equipped and disabled.
NTAK20 is equipped, enabled, and is either locked to a reference or is in
free run mode.
NTAK20 is equipped and is attempting to lock (tracking mode) to a
reference. If the LED flashes continuously over an extended period of time,
check the CC STAT in LD 60. If the CC is tracking this may be an
acceptable state. Check for slips and related clock controller error
conditions. If none exist, then this state is acceptable, and the flashing is
identifying jitter on the reference.
NTAK20 is not equipped.
Definition
clock.