20
MICRO T1 CSU/DSU
Errored Second
: In ESF or SF framing, if the unit detects a frame
error, the ERR LED will flash briefly once a second.
Framing Mismatch
: The ERR LED flashes briefly once a second when
framing modes are mismatched.
Loss of Signal
: When there is no signal at the network interface, the
ERR LED will flash briefly once a second.
TXD
Transmit Data. Lit green to indicate data flow to the Micro T1
CSU/DSU from the DTE.
RXD
Receive Data. Lit green to indicate data flow from the Micro T1
CSU/DSU to DTE.
LOS
Loss of Sync. Lit red to indicate a network Loss of Frame or Loss of
Signal condition.
ALM
Alarm. Lit red to indicate that one of several alarm conditions exists.
These conditions may be local alarms or remote alarm conditions.
Alarms may occur due to Loss of Synchronization, Loss of Frame, AIS
(Blue Alarm), or Yellow Alarm.
ERR
Error. Lit red to indicate the detection of an Errored Second (ES). An
Errored Second is any second in which a SuperFrame or Extended
Superframe error event has occurred.
TST
Test/Loop. Lit yellow to indicate that the unit is in test mode. The unit
may be in any one of the following modes: D4 Line Loop (CO
initiated), ESF Line Loop (CO Initiated), ESF Payload Loop (CO
Initiated).
PWR
Power. Lit green to indicate that the unit is receiving power.
