S/UNI®-JET Data Sheet
Released
In G.751 E3 mode, the E3-TRAN :
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Inserts the RAI bit (bit 11 of the frame) either via a register bit or, optionally, when the
E3-FRMR declares OOF.
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Inserts the National Use reserved bit (bit 12 of the frame) either as a fixed value through a
register bit or from the TDPR block as configured by the TNETOP bit in the S/UNI-JET Data
Link and FERF Control Register and the NATUSE bit in the E3 TRAN Configuration
Register.
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Optionally identifies the tributary justification bits and stuff opportunity bits as either
overhead or payload to SPLT for payload mappings that take advantage of the full bandwidth.
Further, the E3-TRAN can provide insertion of bit errors in the framing pattern or in the parity
bits, and insertion of single LCV for diagnostic purposes. Most of the overhead bits can be
overwritten by using the TOH[x] and TOHINS[x] input pins.
10.15 J2 Transmitter
The J2 Transmitter (J2-TRAN) Block integrates circuitry required to insert the overhead bits into
an J2 bit stream and produce a B8ZS-encoded signal. The J2-TRAN is directly compatible with
the framing format specified in G.704 and NTT Technical Reference for High-Speed Digital
Leased Circuit Services.
The J2-TRAN generates the frame alignment signal and inserts it into the incoming serial stream.
All overhead and status bits in each frame format can be individually controlled by either register
bits or by the transmit overhead stream.
The J2-TRAN inserts:
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The CRC-5 bits calculated over the preceding multiframe.
The x-bits through microprocessor programmable register bits.
The a-bit through a microprocessor programmable register bit.
The m-bit data link through the TDPR block.
Payload AIS or physical layer AIS through microprocessor programmable register bits.
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 LCV for
diagnostic purposes.
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990267, Issue 3
71
PMC [ PMC-SIERRA, INC ]
