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Multi-Service Access Device For Channelized Interfaces
Telecom Standard Product Data Sheet
Production
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990823, Issue 4
28
Provides independent time-slot interchange blocks on the incoming and outgoing
TelecomBus interfaces to allow arbitrary arrangement of timeslots at STS-1 granularity.
Optionally encodes egress data to a set of four working and to a set of four protection
777.6Mbit/s LVDS serial TelecomBus links with 8B/10B-based encoding.
Optionally decodes ingress data from a set of four working or from a set of four protection
777.6MHz LVDS serial TelecomBus links with 8B/10B-based encoding.
Provides redundant working and protection transmit LVDS serial TelecomBus streams and
redundant receive LVDS serial TelecomBus streams for protection switching purposes.
Optionally allows selection of either working or protection serial TelecomBus link data, at the
STS-1 timeslot granularity, to be directed to the device core for POS/HDLC/ATM processing.
Provides encoding and decoding of serial TelecomBus control signals at the multiplex section
termination (MST) point and high-order path termination (HPT) point.
Uses 8B/10B-based line coding protocol on the serial links to provide transition density
guarantee and DC balance and to offer a greater control character vocabulary than the
standard 8B/10B protocol.
Provides optional PRBS generation for each 8-bit bus on the outgoing parallel TelecomBus
interface or for each outgoing LVDS serial TelecomBus link for off-line link verification.
Provides PRBS detection for each 8-bit bus on the incoming parallel TelecomBus interface or
for each incoming LVDS serial TelecomBus link for off-line link verification.
Provides in-service link verification by optionally overwriting and monitoring the B1 and E1
byte of each constituent STS-1/STM-0 with a unique software programmable byte and its
complement.
Provides pins to coordinate updating of the connection map of the timeslot interchange blocks
in the local device, peer and companion PM5310 TBS devices, and companion PM5372 TSE
devices.
2.3
DS3 Demapper/Receiver
Performs STS-1 demapping and destuffing of up to 48 DS3 channels.
Complies with DS3 to STS-1 asynchronous mapping standard as stated in Bellcore, ANSI
and ITU specifications
Performs majority vote C bit decoding to detect stuff requests
Extracts DS3 payload from the STS-1 SPE (VC3) via an elastic store
Uses a simple bit leaking algorithm for the desynchronizer (8 bits are leaked out in four
frames, 500 sec)
Provides DS3 frame synchronization for C-bit parity DS3 applications as per ANSI-107.
DS3 Far end alarm channel code detection is provided.