STANDARD PRODUCT
DATASHEET
PMC-1981125
ISSUE 7
PM8315 TEMUX
HIGH DENSITY T1/E1 FRAMER WITH
INTEGRATED VT/TU MAPPER AND M13 MUX
STM-1/VC4 TUG3 or STM-1/VC3 otherwise no loopback data will get through.
The ingress data path is not affected by the telecom line loopback. This loopback
is only available for VT1.5/VT2/TU11/TU12 mapped tributaries. DS3 mapped
tributaries must use the DS3 line loopback. The Telecom bus line loopback mode
is shown diagrammatically in Figure 46.
Figure 46
- Telecom Line Loopback Diagram
VTPP
VT/TU
Payload
Processor
RTDM
Receive
Tributary
Path O/H
LDDATA[7:0]
LDDP
LDPL
LDC1J1
LADATA[7:0]
LADP
LAPL
LAC1J1V1
LAC1
VTPP
VT/TU
Payload
Processor
TTOP
Transmit
Tributary
Path O/H
12.11 SBI Bus Data Formats
The TEMUX uses the Scaleable Bandwidth Interconnect (SBI) bus as a high
density link interconnect with devices processing T1s, E1s, DS3s and
transparent virtual tributaries. The SBI bus is a multi-point to multi-point bus
capable of interconnecting up to three TEMUX devices in parallel with other link
layer or tributary processing devices.
Multiplexing Structure
The SBI structure uses a locked SONET/SDH structure fixing the position of the
TU-3 relative to the STS-3/STM-1. The SBI is also of fixed frequency and
alignment as determined by the reference clock (SREFCLK) and frame indicator
signal (SC1FP). Frequency deviations are compensated by adjusting the
location of the T1/E1/DS3/TVT1.5/TVT2 channels using floating tributaries as
determined by the V5 indicator and payload signals (SDV5, SAV5, SDPL and
SAPL). TVTs also allow for synchronous operation where SONET/SDH tributary
PROPRIETARY AND CONFIDENTIAL
211
PMC [ PMC-SIERRA, INC ]
