PMC-Sierra PM5349 manual Description

PMC-Sierra, Inc.

S/UNI-QUAD

DATASHEET

PM5349 S/UNI-QUAD

PMC-971239 ISSUE 6 SATURN USER NETWORK INTERFACE (155-QUAD)

7 DESCRIPTION

The PM5349 S/UNI-QUAD SATURN User Network Interface is a monolithic integrated circuit that implements four channel SONET/SDH processing and ATM mapping functions at the STS-3c (STM-1) 155.52 Mbit/s rate.

The S/UNI-QUAD receives SONET/SDH streams using a bit serial interface, recovers the clock and data and processes section, line, and path overhead. It performs framing (A1, A2), de-scrambling, detects alarm conditions, and monitors section, line, and path bit interleaved parity (B1, B2, B3), accumulating error counts at each level for performance monitoring purposes. Line and path far end block error indications (M1, G1) are also accumulated. The S/UNI-QUAD interprets the received payload pointers (H1, H2) and extracts the synchronous payload envelope which carries the received ATM cell payload.

The S/UNI-QUAD frames to the ATM payload using cell delineation. HCS error correction is provided. Idle/unassigned cells may be dropped according to a programmable filter. Cells are also dropped upon detection of an uncorrectable header check sequence error. The ATM cell payloads are descrambled. The ATM cells that are passed are written to a four cell FIFO buffer. The received cells are read from the FIFO using a 16-bit wide Utopia level 2 compliant datapath interface. Counts of received ATM cell headers that are errored and uncorrectable and also those that are errored and correctable are accumulated independently for performance monitoring purposes.

The S/UNI-QUAD transmits SONET/SDH streams using a bit serial interface and formats section, line, and path overhead appropriately. It synthesizes the transmit clock from a lower frequency reference and performs framing pattern insertion (A1, A2), scrambling, alarm signal insertion, and creates section, line, and path bit interleaved parity (B1, B2, B3) as required to allow performance monitoring at the far end. Line and path far end block error indications (M1, G1) are also inserted. The S/UNI-QUAD generates the payload pointer (H1, H2) and inserts the synchronous payload envelope which carries the ATM cell payload. The S/UNI-QUAD also supports the insertion of a large variety of errors into the transmit stream, such as framing pattern errors, bit interleaved parity errors, and illegal pointers, which are useful for system diagnostics and tester applications.

ATM cells are written to an internal four cell FIFO using a 16-bit wide Utopia Level 2 datapath interface. Idle/unassigned cells are automatically inserted when the internal FIFO contains less than one cell. The S/UNI-QUAD provides generation of the header check sequence and scrambles the payload of the ATM cells. Each of these transmit ATM cell processing functions can be enabled or bypassed.

Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use 9