S/UNI®-8x155 ASSP Telecom Standard Product Data Sheet
Released
10.10.5Line FEBE Insert
The Line FEBE Insert Block accumulates line BIP-24 errors (B2) detected by the Receive Line
Overhead Processor and encodes far end block error indications in the transmit Z2 byte.
10.11 Transmit Path Overhead Processor (TPOP)
The Transmit Path Overhead Processor (TPOP) provides transport frame alignment generation,
pointer generation (H1, H2), path overhead insertion and the insertion of path level alarm
signals.
10.11.1Pointer Generator
The Pointer Generator Block generates the outgoing payload pointer (H1, H2) as specified in
the references. The concatenation indication (the NDF field set to 1001, I-bits and D-bits set to
all ones, and unused bits set to all zeros) is inserted in the second and third pointer byte
locations in the transmit stream.
(1) A "normal pointer value" locates the start of the SPE. Note: 0 ? "normal pointer value" ?
782, and the new data flag (NDF) field is set to 0110. Note that values greater than 782 may be
inserted, using internal registers, to generate a loss of pointer alarm in downstream circuitry.
(2) Arbitrary "pointer values" may be generated using internal registers. These new values may
optionally be accompanied by a programmable new data flag. New data flags may also be
generated independently using internal registers.
(3) Positive pointer movements may be generated using a bit in an internal register. A positive
pointer movement is generated by inverting the five I-bits of the pointer word. The SPE is not
inserted during the positive stuff opportunity byte position, and the pointer value is incremented
by one. Positive pointer movements may be inserted once per frame for diagnostic purposes.
(4) Negative pointer movements may be generated using a bit in an internal register. A
negative pointer movement is generated by inverting the five D-bits of the pointer word. The
SPE is inserted during the negative stuff opportunity byte position, the H3 byte, and the pointer
value is decremented by one. Negative pointer movements may be inserted once per frame for
diagnostic purposes.
The pointer value is used to insert the path overhead into the transmit stream. The current
pointer value may be read via internal registers.
10.11.2BIP-8 Calculate
The BIP-8 Calculate Block performs a path bit interleaved parity calculation on the SPE of the
transmit stream. Details are provided in the references. The resulting parity byte is inserted in
the path BIP-8 (B3) byte position of the subsequent frame. BIP-8 errors may be continuously
inserted under register control for diagnostic purposes.
Proprietary and Confidential to PMC-Sierra, Inc., and for its customers’ internal use.
Document No.: PMC- 2010299, Issue 2
82
PMC [ PMC-SIERRA, INC ]
