PM5380-BI PMC-Sierra, Inc., PM5380-BI Datasheet - Page 382

• Manufacturer Part Number: PM5380-BI
• Description: Network Interface, SATURN User Network Interface (8x155) Telecom Standard Product
• Manufacturer: PMC-Sierra, Inc.

Proprietary and Confidential to PMC-Sierra, Inc., and for its customers’ internal use.
Document No.: PMC- 2010299, Issue 2
13.1.5
Figure 18 STS-3c/STM-1 Overhead
Transport Overhead Bytes
A1, A2: The frame alignment bytes (A1, A2) locate the SONET/SDH frame in the STS-
3c/STM-1 serial stream.
J0: The J0 byte is currently defined as the STS-3c/STM-1 section trace byte for SONET/SDH.
J0 byte is not scrambled by the frame synchronous scrambler.
Z0: The Z0 bytes are currently defined as the STS-3c/STM-1 section growth bytes for
SONET/SDH. Z0 bytes are not scrambled by the frame synchronous scrambler.
B1: The section bit interleaved parity byte provides a section error monitoring function. In the
transmit direction, the S/UNI-8x155 calculates the B1 byte over all bits of the previous frame
after scrambling. The calculated code is then placed in the current frame before scrambling. In
the receive direction, the S/UNI-8x155 calculates the B1 code over the current frame and
compares this calculation with the B1 byte received in the following frame. B1 errors are
accumulated in an error event counter.
D1 - D3: The section data communications channel provides a 192 kbit/s data communications
channel for network element to network element communications. In the transmit direction, the
section DCC byte is inserted from a dedicated 192 kbit/s input, TDCC[7:0], when the channel is
configured for section DCC. In the receive direction, the section DCC is extracted on a
dedicated 192 kbit/s output, RDCC[7:0], when the channel is configured for section DCC.
H1, H2: The pointer value bytes locate the path overhead column in the SONET/SDH frame. In
the transmit direction, the S/UNI-8x155 inserts a fixed pointer value, with a normal new data
flag indication in the first H1-H2 pair. The concatenation indication is inserted in the remaining
H1-H2 pairs (STS-3c/STM-1). Pointer movements can be induced using the TPOP registers. In
the receive direction, the pointer is interpreted to locate the SPE. The loss of pointer state is
entered when a valid pointer cannot be found. Path AIS is detected when H1, H2 contain an all
ones pattern.
H3: The pointer action bytes contain synchronous payload envelope data when a negative stuff
event occurs. The all zeros pattern is inserted in the transmit direction. This byte is ignored in
the receive direction unless a negative stuff event is detected.
D10
A1
B1
D1
H1
B2
D4
D7
S1
A1
H1
B2
Z1
STS-3c Transport Overhead
A1
H1
B2
Z1
STM-1 Section Overhead
D11
A2
E1
D2
H2
K1
D5
D8
Z2
H2
A2
Z2
H2
M1
A2
D12
F1
D3
H3
K2
D6
D9
E2
J0
Z0
H3
H3
Z0
S/UNI®-8x155 ASSP Telecom Standard Product Data Sheet
Released
382