PM7346 datasheet(97/419 Pages) PMC

97 / 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 76

The J2-TRAN:

• inserts the CRC-5 bits calculated over the preceding multiframe;

• inserts the x-bits through microprocessor programmable register bits;

• inserts the a-bit through a microprocessor programmable register bit;

• inserts the m-bit data link through the TDPR block;

• inserts payload AIS or physical layer AIS through microprocessor

programmable register bits;

• inserts RAI over the m-bits, overwriting HDLC frames, by using the XBOC

block or through automatic activation upon detection of certain remote alarm

conditions.

The J2-TRAN allows overwriting of any of the overhead bits by using the TOH[x],

TOHINS[x], TOHFP[x], and TOHCLK[x] overhead signals. Further, the J2-TRAN

can provide insertion of single bit errors in the framing pattern or in the CRC-5

bits, and insertion of single line code violations for diagnostic purposes.

9.16 XBOC Bit Oriented Code Generator

The Bit Oriented Code Generator (XBOC) Block transmits 63 of the possible 64

bit oriented codes (BOC) in the C-bit parity Far End Alarm and Control (FEAC)

channel. A BOC is a 16-bit sequence consisting of 8 ones, a zero, 6 code bits,

and a trailing zero (111111110xxxxxx0) which is repeated as long as the code is

not 111111. The code to be transmitted is programmed by writing the XBOC

Code Register. The 64th code (111111) is similar to the HDLC idle sequence

and is used to disable the transmission of any bit oriented codes. When

transmission is disabled, the FEAC channel is set to all ones.

9.17 TDPR Facility Data Link Transmitter

The Facility Data Link Transmitter (TDPR) provides a serial data link for the C-bit

parity path maintenance data link in DS3, the serial Network Operator byte or the

General Purpose datalink in G.832 E3, the National Use bit datalink in G.751 E3,

or the m-bit datalink in J2. The TDPR is used under microprocessor control to

transmit HDLC data frames. It performs all of the data serialization, CRC

generation, zero-bit stuffing, as well as flag, and abort sequence insertion. Upon

completion of the message, a CRC-CCITT frame check sequence (FCS) can be

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