PMC-Sierra, Inc.
PRELIMINARY
PM5381 S/UNI-2488
DATASHEET
PMC-2000489
ISSUE 1
SATURN USER NETWORK INTERFACE FOR 2488 MBIT/S
H1, H2:
The pointer value bytes locate the path overhead column in the SONET/SDH
frame.
In the transmit direction, the S/UNI-622-POS 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-48c (STM-16c)).
Pointer movements can be induced using the THPP 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:
B2:
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.
The line bit interleaved parity bytes provide a line error monitoring function.
In the transmit direction, the S/UNI-2488 calculates the B2 values. The
calculated code is then placed in the next frame.
In the receive direction, the S/UNI-2488 calculates the B2 code over the
current frame and compares this calculation with the B2 code receive in the
following frame. Receive B2 errors are accumulated in an error event counter.
K1, K2:
The K1 and K2 bytes provide the automatic protection switching channel. The
K2 byte is also used to identify line layer maintenance signals. Line RDI is
indicated when bits 6, 7, and 8 of the K2 byte are set to the pattern '110'. Line
AIS is indicated when bits 6, 7, and 8 of the K2 byte are set to the pattern
'111'.
In the transmit direction, the S/UNI-2488 provides register control for the K1
and K2 bytes.
In the receive direction, the S/UNI-2488 provides register access to the filtered
APS channel. Protection switch byte failure alarm detection is provided. The
K2 byte is examined to determine the presence of the line AIS, or the line RDI
maintenance signals
D4 - D12:
The line data communications channel provides a 576 kbit/s data
communications channel for network element to network element
communications.
S1:
The S1 byte provides the synchronization status byte. Bits 5 through 8 of the
synchronization status byte identifies the synchronization source of STS-48c
(STM-16c) signal. Bits 1 through 4 are currently undefined.
Proprietary and Confidentail to PMC-Sierra Inc., and for its Customer’s Internal Use
435
PMC [ PMC-SIERRA, INC ]
