S/UNI®-JET Data Sheet
Released
Transmission System
Sublayer Processing
Transmit or Detected Features
Receive
J2
Receive
LCV, LOS, LOF, framing bit errors, physical layer AIS,
payload AIS, CRC-5 errors, Remote End Alarm, and RAI
In the E3 receive direction, the S/UNI-JET frames to G.751 and G.832 E3 signals with a
maximum average reframe times of 135 µs for G.751 frames and 250 µs for G.832 frames. LCVs,
LOS, framing bit errors, AIS, and remote alarm indication (RAI) are detected. Further, when
processing G.832 formatted data, parity errors, far end receive failure, and far end block errors are
also detected; and the Trail Trace message can be extracted and made available through the
microprocessor port. HDLC receivers are provided for either the G.832 Network Requirement or
the G.832 General Purpose Data Link support.
In the J2 receive direction, the S/UNI-JET frames to G.704 6.312 MHz signals with a maximum
average reframe time of 5.07 ms. An alternate framing algorithm that uses the CRC-5 bits to rule
out 99.9% of all static mimic framing patterns is available with a maximum average reframe time
4
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of 10.22 ms when operating with a 10 bit error rate. The alternate framing algorithm can be
selected by the CRC_REFR bit in the J2-FRMR Configuration Register. LCV, LOS, loss of frame
(LOF), framing bit errors, physical layer AIS, payload AIS, CRC-5 errors, Remote End Alarm,
and RAI are detected. HDLC receivers are provided for Data Link support.
Error event accumulation is also provided by the S/UNI-JET. Framing bit errors, LCV, parity
errors, path parity errors, and far end block errors (FEBE) are accumulated, when appropriate, in
saturating counters for DS3, E3, and J2 frames. LOF detection for DS3, E3, and J2 is provided as
recommended by ITU-T G.783 with integration times of 1ms, 2ms, and 3ms.
In the DS3 transmit direction, the S/UNI-JET inserts DS3 framing, X and P bits. When enabled
for C-bit parity operation, bit-oriented code transmitters and HDLC transmitters are provided for
the insertion of FEAC channels and the PMDL in the appropriate overhead bits. AIS can be
inserted by using internal register bits and other status signals such as the idle signal can be
inserted when enabled by internal register bits. When M23 operation is selected, the C-bit Parity
ID bit (the first C-bit of the first M sub-frame) is forced to toggle so that downstream equipment
will not confuse an M23-formatted stream with stuck-at 1 C-bits for C-bit parity application.
In the E3 transmit direction, the S/UNI-JET inserts E3 framing in either G.832 or G.751 format.
When enabled for G.832 operation, an HDLC transmitter is provided so that the Network
Requirement or General Purpose Data Link is inserted into the appropriate overhead bits. The
AIS and other status signals can be inserted by internal register bits.
In the J2 transmit direction, the S/UNI-JET inserts J2 6.312 Mbit/s G.704 framing. HDLC
transmitters are provided the Data Links are inserted. CRC-5 check bits are calculated and
inserted into the J2 multiframe. External pins are provided so that any of the overhead bits within
the J2 frame can be overwritten.
The S/UNI-JET also supports diagnostic options that allow it to insert, when appropriate, the
transmit framing format, parity or path parity errors, F-bit framing errors, M-bit framing errors,
invalid X or P-bits, LCV, all-zeros, AIS, RAIs, and Remote End Alarms.
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990267, Issue 3
30
PMC [ PMC-SIERRA, INC ]
