PM4332 datasheet(60/446 Pages) PMC

60 / 446 page

PRELIMINARY

PM4332 TE-32

DATA SHEET

PMC-2011402

ISSUE 1

HIGH DENSITY 32 CHANNEL T1/E1/J1 FRAMER

PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR THE INTERNAL USE OF ITS CUSTOMERS

frame condition and all-ones in the PCM data stream have been present for 2.55

sec (±40 ms); the AIS alarm is removed when the AIS condition has been absent

for 16.6 sec (±500 ms).

CFA alarm detection algorithms operate in the presence of a 10-3 bit error rate.

9.1.3.1 Customer Interface Alarms

The RAI-CI and AIS-CI alarms defined in T1.403 are detected reliably.

By definition, RAI-CI is a repetitive pattern within the ESF data link with a period

of 1.08 seconds. It consists of sequentially interleaving 0.99 seconds of

00000000 11111111 (right-to-left) with 90 ms of 00111110 11111111.

RAI-CI is declared when a bit oriented code of “00111110 11111111” is validated

(i.e. two consecutive patterns) while RAI (a.k.a. Yellow alarm) is declared. RAI-CI

is cleared upon deassertion of RAI or upon 28 consecutive 40ms intervals

without validation of “00111110 11111111”.

By definition, AIS-CI is a repetitive pattern of 1.26 seconds. It consists of 1.11

seconds of an unframed all ones pattern and 0.15 seconds of all ones modified

by the AIS-CI signature. The AIS-CI signature is a repetitive pattern 6176 bits in

length in which, if the first bit is numbered bit 0, bits 3088, 3474 and 5790 are

logical zeros and all other bits in the pattern are logical ones. AIS-CI is an

unframed pattern, so it is defined for all framing formats.

AIS-CI is declared between 1.40 and 2.56 seconds after initiation of the AIS-CI

signal and is deasserted 16.6 seconds after it ceases.

9.2 E1 Framing

E1 framing can be performed on up to 32 tributaries.

The E1 framing function searches for basic frame alignment, CRC multiframe

alignment, and channel associated signaling (CAS) multiframe alignment in the

incoming recovered PCM stream.

Once basic (or FAS) frame alignment has been found, the incoming PCM data

stream is continuously monitored for FAS/NFAS framing bit errors, which are

accumulated in a framing bit error counter dedicated to each tributary. Once

CRC multiframe alignment has been found, the PCM data stream is continuously

monitored for CRC multiframe alignment pattern errors and CRC-4 errors, which

are accumulated in a CRC error counter dedicated to each tributary. Once CAS

multiframe alignment has been found, the PCM data is continuously monitored

PM4332 Datasheet(PDF) 60 Page - PMC-Sierra, Inc