PM5347 datasheet(83/302 Pages) PMC

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PM5347 S/UNI-PLUS

DATA SHEET

PMC-941033

ISSUE 6

SATURN USER NETWORK INTERFACE PLUS

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

error control octet and the forty-eight octet payload. The second data structure

consists of fifty-three 8-bit words comprising the five octet cell header and the

forty-eight octet payload. Refer to the Operation section for more detail on these

data structures.

Management functions include filling the transmit FIFO, indicating when cells are

available to be written to the transmit FIFO, maintaining the transmit FIFO read

and write pointers, and detecting a FIFO overrun condition. The FIFO depth can

be programmed to be one to four cells deep. The TCA output signal transitions

low to indicate a full FIFO when the FIFO contains the same number of cells as

the programmed FIFO depth. Note, a cell is not transmitted by the S/UNI-PLUS

until the full cell has been written into the FIFO.

When the FIFO is full as indicated by TCA and the upstream device writes into

the FIFO, the TACP indicates a FIFO overrun condition using a maskable

interrupt and register bits. The offending write and all subsequent writes are

ignored until there is room in the FIFO.

The FIFO interface provided to the system is a synchronous interface emulating

commercial synchronous FIFOs. All transmit FIFO signals, TSOC, TWRENB,

TCA, TXPRTY[1:0] and TDAT[15:0] are either sampled or updated on the rising

edge of the TFCLK clock input.

9.17

SONET/SDH Section and Path Trace Buffers

The SONET/SDH Section Trace Buffer (SSTB) block and the SONET/SDH Path

Trace Buffer (SPTB) block are identical. The blocks can handle both 64-byte

CLLI messages in SONET and 16-byte E.164 messages in SDH. The generic

SONET/SDH Trace Buffer (STB) block is described below.

9.17.1 Receive Trace Buffer (RTB)

The RTB consists of two parts: the Trace Message Receiver and the Overhead

Byte Receiver.

1. Trace Message Receiver:

The Trace Message Receiver (TMR) processes the trace message, and

consists of three sub-processes: Framer, Persistency, and Compare.

Framer:

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