PM7344 datasheet(169/293 Pages) PMC

169 / 293 page

PM7344 S/UNI-MPH

DATA SHEET

PMC-950449

ISSUE 6

MULTI-PHY USER NETWORK INTERFACE

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

153

signalling data nibble in the lower four bits of the time slot byte. A logic 0 in

the DLEN bit position is reserved and should not be used.

GENCRC:

The GENCRC bit enables generation of the CRC multiframe. When

GENCRC is a logic 1, the E1-TRAN generates the CRC multiframe alignment

signal, calculates and inserts the CRC bits, and if enabled by FEBEDIS,

inserts the FEBE indication in the spare bit positions. When GENCRC is set

to logic 0, the CRC generation is disabled. The CRC bits are then set to the

logic value contained in the Si[1] bit position in the International/National Bit

Control Register and bit 1 of the NFAS frames are set to the value of Si[0] bit.

FDIS:

The FDIS bit value controls the generation of the framing alignment signal. A

logic 1 in the FDIS bit position disables the generation of the framing pattern

in TS0. A logic 0 in FDIS enables the generation of the framing pattern,

replacing TS0 of frames 0,2,4,6,8,10,12,14 with the frame alignment signal.

When FDIS is a logic 1, framing is globally disabled and the values in controls

bits GENCRC and FEBEDIS are ignored.

Note that the above is true only if the AIS bit in the Transmit Alarm /

Diagnostic Control Register is a logic 0. If AIS is logic 1, the output bit stream

becomes all ones unconditionally.

GENCRC and FEBEDIS:

When FDIS is a logic 0, the bit values used for the International and National

bits are dependent upon the values of the GENCRC and FEBEDIS

configuration bits, as follows:

GENCRC

FEBEDIS

Source of International/National bits

Bit Si[1] of the International/National Control

frame alignment signal (FAS) frames and the Si[0]

bit is used for the International bit in the non-frame

alignment signal (NFAS) frames. Bits Sn[4:8] in

the register are used for the National bits in NFAS

frames.

PM7344 Datasheet(PDF) 169 Page - PMC-Sierra, Inc