Module Descriptions, RFL 9508D Digital Section
8.1.12.3
RX, BPV AND FRM INDICATORS
Three LED indicators on the CM4 module (RX, BPV and FRM) indicate the status of the received T1
signal. The meaning of each of these indicators appears in Table 8-11.
RFL 9508D UCC
RFL Electronics Inc.
Table 8-13. RX, BPV and FRM Indicators
G G G
LOOP INT EXT
G Y R
TX LPBK ERR
G Y R
RX BPV FRM
Item
Module Label Description
(Fig. 8-5)
15 CM4
RX
Receive Input indicator (green); indicates receive status:
ON: A valid T1 data signal is detected at the CM4 T1 receiver
input.
OFF: No receive signal is detected.
BLINKING: One of the following signals or conditions is detected.
(View the BLNK group, Paragraph 5.9, to determine
which condition is causing the blinking.)
Rx11: All ones produced by an idle shelf at the far end, framed or
unframed.
RxY1: Remote alarm, indicating a loss of receive signal at the far
end, if the equipment at the far end is set up to generate
a yellow alarm.
XsJt: Excessive jitter, indicating that the jitter buffer depth has
been exceeded.
FTIM The CM4 transmitter is in fallback internal timing mode.
BPV
Bipolar Variations indicator (yellow). Flashes once each time a bipolar
violation is detected, and remains on continuously above a random BPV
(bipolar variations) error ratio of about 10-5.
FRM
Out-Of-Frame indicator (red). Lights when the CM4 T1 receiver is not in
frame synchronization. This can indicate either a high bit error ratio, or
improper CM4 configuration.
March 11, 2010
8-20
(973) 334-3100
