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CXR Larus 80-100-400 Issue 2 July 2006 page
3-25
INPUT A
Green
Input A select, tracking
INPUT B
Green
Input B select, tracking
HOLD Yellow Hold
ACQUIRE Green
Acquiring
data
LOCKED Green
Locked
FREERUN Yellow
Free
run
ACTIVE Green Driving
outputs
3.3540 Controls and Monitoring:
a. Test pushbutton (press for up to 6 seconds). In the tracking state, momentary
hold test; display shows 'H' if successful. This does not disrupt tracking. In the
invalid output state, resets tracking algorithm to FREERUN state; display shows
'r'. (An internal TEST/RUN toggle, S2, is set in RUN mode for normal operation.)
b. Monitor jack (-20 dB), framed all ones at clock output frequency.
c. Software control for setting SF/ESF or CCS/CAS framing on both input channels.
d. EEPROM for storing last best guess for DDFS.
e. Flash EPROM for software updates.
f. Temperature sensor for future software algorithms for temperature compensated
holdover.
g. Predictive holdover feature that remembers the average correction it has been
making and continues the average correction while in holdover to cancel aging.
3.3541 Seven Segment Status Display:
a. Status conditions while in tracking or acquisition state (display blinks every 1 to
2 seconds):
.
ACQUIRE 1 state (single dot).
o
At top of display: Normal tracking, no phase error. Alternates with
display of input reference.
o
At bottom of display: Correction in progress due to more than 1/4 bit
phase change.
P
Displayed momentarily immediately after power-up if input card is T1
type (54511) or CC/5 MHz/10 MHz (54513-3, -4, -5).
E
Displayed momentarily immediately after power-up if input card is E1
type (54512-4).
NOTE:
For the clock card to detect an E1 type of input card, the input card itself must be
present. Without an E1 input card physically plugged in, the clock card will default to
