PM5347 datasheet(63/302 Pages) PMC

63 / 302 page

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

successive frames have been received, where no three consecutive frames

contain identical K1 bytes. The protection switching byte failure alarm is removed

upon detection of three consecutive frames containing identical K1 bytes. The

detection of invalid APS codes is done in software by polling the S/UNI-PLUS

Receive K1 Register and the S/UNI-PLUS Receive K2 Register.

Error Monitor

The Error Monitor Block calculates the received line BIP-8/24 error detection

code (B2) based on the line overhead and synchronous payload envelope of the

receive stream. The line BIP code is a bit interleaved parity calculation using

even parity. Details are provided in the references. The calculated BIP code is

compared with the BIP code extracted from the B2 bytes of the following frame.

Any differences indicate that a line layer bit error has occurred. Up to 192000 (24

x 8000) bit errors can be detected per second.

The Error Monitor Block accumulates these line layer bit errors in a 20 bit

saturating counter that can be read via the microprocessor interface. During a

read, the counter value is latched and the counter is reset to 0 (or 1, if there is an

outstanding event). Note, this counter should be polled at least once per second

to avoid saturation which in turn may result in missed bit error events.

The Error Monitor Block also accumulates line far end block error indications

(contained in the M0 or M1 byte) in a similar manner.

9.5

Transport Overhead Extract Port

The Transport Overhead Extract Port extracts the entire receive transport

overhead on RTOH for optional external TOH processing. RTOHFP is provided

to identify the most significant bit of the A1 framing byte on RTOH. The transport

overhead clock, RTOHCLK is nominally a 5.184 MHz (STS-3c/STM-1 mode) or a

1.728 MHz (STS-1 mode) clock. RTOH and RTOHFP are updated on the falling

edge of RTOHCLK.

9.6

Receive Path Overhead Processor

The Receive Path Overhead Processor (RPOP) provides pointer interpretation,

extraction of path overhead, extraction of the synchronous payload envelope,

and path level alarm indication and performance monitoring.

PM5347 데이터시트(PDF) 63 Page - PMC-Sierra, Inc