PM7346 datasheet(94/419 Pages) PMC

94 / 419 page

PM7346 S/UNI-QJET

DATASHEET

PMC-960835

ISSUE 6

SATURN QUAD USER NETWORK INTERFACE FOR J2, E3, T3

PMC-SIERRA, INC. PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA INC., AND ITS CUSTOMERS’ INTERNAL USE 73

that no events are missed. The data is then available in the holding registers

until the next accumulation. In addition to the two counters, a record of the 32

bits received immediately prior to the accumulation is available.

The PRGD may also be programmed to check for repetitive sequences. When

configured to detect a pattern of length N bits, the PRGD will load N bits from the

detected stream, and determine whether the received pattern repeats itself every

N subsequent bits. Should it fail to find such a pattern, it will continue loading

and checking until it finds a repetitive pattern. All the features (error counting,

auto-synchronization, etc.) available for pseudo-random sequences are also

available for repetitive sequences. Whenever a PRGD accumulation is forced,

the PRGD stores a snapshot of the 32 bits received immediately prior to the

accumulation. This snapshot may be examined in order to determine the exact

nature of the repetitive pattern received by PRGD.

The pseudo-random or repetitive pattern can be inserted/extracted in the PLCP

payload (if PLCP framing is enabled) or in the DS3, E3, J2, or Arbitrary framing

format payload (if PLCP framing is disabled). It cannot be inserted into the ATM

cell payload.

9.13 DS3 Transmitter

The DS3 Transmitter (T3-TRAN) Block integrates circuitry required to insert the

overhead bits into a DS3 bit stream and produce a B3ZS-encoded signal. The

T3-TRAN is directly compatible with the M23 and C-bit parity DS3 formats.

Status signals such as far end receive failure (FERF), the alarm indication signal,

and the idle signal can be inserted when their transmission is enabled by internal

combination of LOS, OOF or RED, or AIS by the T3-FRMR.

A valid pair of P-bits is automatically calculated and inserted by the T3-TRAN.

When C-bit parity mode is selected, the path parity bits, and far end block error

(FEBE) indications are automatically inserted.

When enabled for C-bit parity operation, the FEAC channel is sourced by the

XBOC bit-oriented code transmitter. The path maintenance data link messages

are sourced by the TDPR data link transmitter. These overhead signals can also

be overwritten by using the TOH[x] and TOHINS[x] inputs.

When enabled for M23 operation, the C-bits are forced to logic 1 with the

exception of the C-bit Parity ID bit (first C-bit of the first M-subframe), which is

forced to toggle every M-frame.

PM7346 Folha de dados(PDF) 94 Page - PMC-Sierra, Inc