HARDWARE MANUAL

The XRT79L74 is a four channel, ATM UNI/PPP Physical Layer Processor with integrated DS3/E3 framing controllers and Line Interface Units with Jitter Attenuators that are designed to support ATM direct mapping and cell delineation as well as PPP mapping and Frame processing.

GENERAL FEATURES:

? Integrated T3/E3 Line Interface Unit

? Integrated Jitter Attenuator that can be selected either in Receive or Transmit path

? Flexible integrated Clock Multiplier that takes single frequency clock and generates either DS3 or E3 frequency.

? 8/16 bit UTOPIA Level I and II and PPP Multi-PHY Interface operating at 25, 33 or 50 MHz.

? HDLC Controller that provides the mapping/extraction of either bit or byte mapped encapsulated packet from DS3/E3 Frame.

? Contains on-chip 16 cell FIFO (configurable in depths of 4, 8, 12 or 16 cells), in both the Transmit (TxFIFO) and Receive Directions (RxFIFO)

? Contains on-chip 54 byte Transmit and Receive OAM Cell Buffer for transmission, reception and processing of OAM Cells

? Supports ATM cell or PPP Packet Mapping

? Supports M13 and C-Bit Parity Framing Formats

? Supports DS3/E3 Clear-Channel Framing.

? Includes PRBS Generator and Receiver

? Supports Line, Cell, and PLCP Loop-backs

? Interfaces to 8 Bit wide Intel, Motorola or PowerPC

? Low power 3.3V, 5V Input Tolerant, CMOS

? Available in 456 Lead PBGA Package

? JTAG Interface

APPLICATIONS

? Digital Access and Cross Connect Systems

? 3G Base Stations

? DSLAMs

? Digital, ATM, WAN and LAN Switches