![](http://datasheet.mmic.net.cn/330000/PM8315_datasheet_16444435/PM8315_128.png)
STANDARD PRODUCT
PM8315 TEMUX
DATASHEET
PMC-1981125
ISSUE 7
HIGH DENSITY T1/E1 FRAMER WITH
INTEGRATED VT/TU MAPPER AND M13 MUX
PROPRIETARY AND CONFIDENTIAL
113
Table 8
- DS3 desynchronizer clock gapping algorithm.
Row Number
Normal or DS3 AIS
Run Faster
Run Slower
1
621
621
621
2
621
621
621
3
622
622
622
4
621
621
621
5
621
622
621
6
622
622
621
7
621
621
621
8
621
622
621
9
622
622
621
9.33 Transmit Tributary Path Overhead Processor (TTOP)
The Transmit Tributary Path Overhead Processor (TTOP) generates the path
overhead for up to 28 VT1.5/TU-11s or 21 VT2/TU-12s.
When configured for SONET compatible operation, the TTOP inserts the four
tributary path overhead bytes (V5, J2, Z6, and Z7) to each tributary. The TTOP
may also be configured for SDH compatible operation. The incoming STM-1
stream may carry three AU3s or an AU4 with three TUG3s.
The TTOP computes the BIP-2 code in the current tributary SPE and inserts the
result into the BIP-2 bits of the V5 byte in the next tributary SPE. The tributary
path signal label in the V5 byte of each tributary can be sourced from internal
registers. The tributary far end block error bit in the V5 byte of each tributary is
inserted based of the BIP error count detected at a companion RTOP TSB. The
tributary remote failure indication and remote defect indication bits in the V5 or
the Z7 byte of each tributary is inserted based on the tributary alarm status from
the companion Tributary Remote Alarm Processor, TRAP, TSB.
The TTOP inserts the tributary trail trace identifier into the J2 byte. Each
tributary is provided with a 64-byte buffer to store the identifier. One shadow
buffer is available for temporary replacement of a selected transmitted TTI while
the 64-byte identifier buffer is being updated. Data is retrieved sequentially from
the active buffer at each J2 byte position. The shadow buffer can be
programmed with new messages without timing constraints when inactive. An
inactive 64-byte identifier buffer can also be programmed with new messages