ds2152 Maxim Integrated Products, Inc., ds2152 Datasheet - Page 36

• Manufacturer Part Number: ds2152
• Description: Ds2152 Enhanced T1 Single Chip Transceiver
• Manufacturer: Maxim Integrated Products, Inc.

Table 5-2. Alarm Criteria
Note 1: The definition of Blue Alarm (or Alarm Indication Signal) is an unframed all 1s signal. Blue alarm detectors should be able to
operate properly in the presence of a 10-3 error rate and they should not falsely trigger on a framed all 1s signal. The blue alarm criteria in
the DS2152 have been set to achieve this performance. It is recommended that the RBL bit be qualified with the RLOS bit.
Note 2: ANSI specifications use a different nomenclature than the DS2152 does; the following terms are equivalent:
Blue Alarm (AIS)
(See note 1 below)
Yellow Alarm (RAI)
1. D4 bit 2 mode(RCR2.2 = 0)
2. D4 12
3. ESF mode
Red Alarm (LRCL)
(This alarm is also referred to as
Loss Of Signal)
(RCR2.2=1; this mode is also
referred to as the "Japanese
Yellow Alarm"
th
F-bit mode
ALARM
When over a 3ms window, five or
less 0s are received
When bit 2 of 256 consecutive
channels is set to 0 for at least 254
occurrences
When the 12
1 for two consecutive occurrences
When 16 consecutive patterns of
00FF appear in the FDL
When 192 consecutive 0s are
received
SET CRITERIA
th
RLOS = LOF
LRCL = LOS
RYEL = RAI
RBL = AIS
framing bit is set to
36 of 97
When over a 3ms window, six or
more 0s are received
When bit 2 of 256 consecutive
channels is set to 0 for less than 254
occurrences
When the 12
for two consecutive occurrences
When 14 or less patterns of 00FF
hex out of 16 possible appear in the
FDL
When 14 or more 1s out of 112
possible bit positions are received
starting with the first one received
CLEAR CRITERIA
th
framing bit is set to 0