S/UNI®-JET Data Sheet
Released
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The Payload Type bits and buffers them so that they can be read by the microprocessor.
The Timing Marker bit and asserts the Timing Marker indication when the value of the
extracted bit has been in the same state for three or five consecutive frames.
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The Network Operator byte and presents it as a serial stream for further processing by the
RDLC block when the RNETOP bit in the S/UNI-JET Data Link and FERF Control Register
is logic one. The byte is also brought out on the ROH[x] output with an associated clock on
ROHCLK[x]. All eight bits of the Network Operator byte are extracted and presented on the
overhead output and, optionally, presented to the RDLC.
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The General Purpose Communication Channel byte and presents it to the RDLC when the
RNETOP bit in the S/UNI-JET Data Link and FERF Control Register is logic zero The byte
is also brought out on the ROH[x] output with an associated clock on ROHCLK[x].
In G.751 E3 mode, the E3-FRMR extracts:
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The RAI bit (bit 11 of the frame) and indicates a Remote Alarm when the RAI bit is a logic
one for three or five consecutive frames. Similarly, the Remote Alarm is removed when the
RAI bit is logic zero for three or five consecutive frames.
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The National Use reserved bit (bit 12 of the frame) and presents it as a serial stream for
further processing in the RDLC when the RNETOP bit in the S/UNI-JET Data Link and
FERF Control Register is logic zero. The bit is also brought out on the ROH[x] output with
an associated clock on ROHCLK[x]. Optionally, an interrupt can be generated when the
National Use bit changes state.
Further, while in-frame, the E3-FRMR indicates the position of all the overhead bits in the
incoming digital stream to the ATMF/SPLR block. For G.751 mode, the tributary justification bits
can be optionally identified as either overhead or payload for payload mappings that take
advantage of the full bandwidth.
The E3-FRMR declares OOF alignment if the framing pattern is in error for four consecutive
frames. The E3-FRMR is an "off-line" framer, where all frame alignment indications, all
overhead bit indications, and all overhead bit processing continue based on the previous
alignment. Once the framer has determined the new frame alignment, the OOF indication is
removed and a COFA indication is declared if the new alignment differs from the previous
alignment.
The E3-FRMR detects the presence of AIS in the incoming data stream when less than eight zeros
in a frame are detected while the framer is OOF in G.832 mode, or when less than five zeros in a
frame are detected while OOF in G.751 mode. This algorithm provides a probability of detecting
-3
AIS in the presence of a 10 BER as 92.9% in G.832 and 98.0% in G.751.
LOS is declared when no marks have been received for 32 consecutive bit periods. LOS de-
asserted after 32 bit periods during which there is no sequence of four consecutive zeros.
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990267, Issue 3
57
PMC [ PMC-SIERRA, INC ]
