Exar
Corporation 48720 Kato Road, Fremont CA, 94538
(510) 668-7000
FAX (510) 668-7017
www.exar.com
PRELIMINARY
XRT95L34
OC-12/STM-4, QUAD OC-3/STM-1 POS/ATM FRAMER WITH INTEGRATED CDR'S
MARCH 2002
REV. P1.0.0
GENERAL DESCRIPTION
The XRT95L34 is an OC-12/STM-4, Quad OC-3/
STM-1 POS/ATM Framer with integrated CDR's. ATM
direct mapping and cell delineation are supported, so
are packets (PPP) over SONET for POS mapping
and frame processing. The XRT95L34 contains an in-
tegral SONET framer which provides framing and er-
ror accumulation in accordance with ANSI/ITU-T
specifications. The configuration of this device is
through internal registers accessible via an 8-bit par-
allel, memory mapped, microprocessor interface.
APPLICATIONS
Edge and WAN ATM Switches
IP Routers, Packet Switches and Hubs
Multi-protocol Switches
FEATURES
A single chip solution for ATM UNI and packet over
SONET
Provides the highest level of protection switching
flexibility for up to 1:14 protected OC-3/STM-1
ports.
Provides quad serial OC-3/STM-1 interfaces with
integrated CDR, compatible with industry standard
optical modules.
Provides serial OC-12/STM-4 interfaces with inte-
grated CDR, compatible with industry standard
optical modules.
Supports the mappings for any standard combina-
tion of STS-12c/AU-4c or STS-3c/AU4.
Provides four 8-bit busses on the line side running
at 19.44 MHz to connect OC-12 framers through a
parallel interface or aggregate four low speed OC-3
devices into an OC-12 line.
Supports both SONET and SDH on all interfaces.
SONET/SDH is programmable per interface.
Terminates Section Overhead, Line Overhead and
STS-Path Overhead on 4xOC-3, 1xOC-12 inter-
faces. Supports performance monitoring and
alarms required by GR.253, G.707 and ANSI
T1.105.
Provides SONET frame scrambling and de-scram-
bling.
Supports 50 msecond APS by monitoring and filter-
ing K1 and K2 bytes as required by the standards.
Offers differential line interfaces.
Offers multiple microprocessor compatible interface
- Intel, Motorola, PowerPC, Mips.
Provides 8/16-bit data UTOPIA level II Interface and
POS interface.
Includes ATM cell or PPP packet Mapping.
Single +3.3V power supply with +5V input toler-
ance.
SONET TRANSMITTER
Performs standard OC-3c/STM-1c transmit pro-
cessing.
Conforms to ITU-T I.432, ANSI T1.105, and
Bellcore-253.
SONET RECEIVER
Performs standard STS-12/STS-3c/STM-1c receive
processing.
Conforms to ITU-T I.432, ANSI T1.105, and
Bellcore-253.
HIGH SPEED INTERFACE
Quad serial OC-3/STM-1 PECL interfaces with inte-
grated CDR, compatible with industry standard
optical modules.
Single serial OC-12/STM-4 PECL interface with
integrated CDR, compatible with industry standard
optical modules.
LOW SPEED INTERFACE
Complies with ATM forum Utopia Level 2 Specifica-
tion
Supports 8/16-bit 50MHz transmit and receive
interface.
Provides up to total 16 cell buffers for transmit and
receive.
MICROPROCESSOR INTERFACE
Supports standard 8-bit micro-controllers with Intel
or Motorola style interfaces.
33 MHz read and write access.
Provides burst bus transfers.
Provides DMA controller interface for OAM buffer
interface.
Separated and multiplexed data/address bus.
Both write-clear and reset-upon-read for control of
status registers.
Provides interrupts for alarm processing.
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