S/UNI®-JET Data Sheet
Released
The Receive PLCP Overhead diagram (Figure 42) shows the extraction of the PLCP path
overhead bits on the RPOH output, along with overhead clock (RPOHCLK), and PLCP frame
position indicator (RPOHFP). The path overhead octets are shifted out in order with the most
significant bit (bit 1) of each octet first. The number of growth octets (Zn) in the PLCP frame
varies according to the selected PLCP frame format (DS3, DS1, G.751 E3, or E1). The PLCP
frame position indicator (RPOHFP) is set high once per PLCP frame period, during bit 1 of the
F1 octet, and indicates the 8 kHz receive PLCP frame timing.
Figure 43 Transmit DS1 Stream
TICLK
TCLK]
Framing Octet 1
Position Bit 1
Octet 24 Octet 24 Octet 24 Octet 24 Overhead Octet 1
Bit 5 Bit 6 Bit 7 Bit 8 Slot Bit 1
TDATO
TOHM
The Transmit DS1 Stream diagram (Figure 43) illustrates the generation of DS1 overhead
indicators on TOHM when the S/UNI-JET is configured for DS1 PLCP or non-PLCP frame
formats. The S/UNI-JET flywheels using its internal timeslot counter to generate TOHM. The
ATM cell stream is inserted in TDATO, along with a framing bit placeholder every 193 bit
periods. An upstream DS1 framer (such as the PM4341A T1XC or PM4344 TQUAD) must be
used to insert the appropriate DS1 framing pattern. Note: TCLK is a flow through version of
TICLK; a variable propagation delay exists between these two signals.
Figure 44 Transmit E1 Stream
TICLK
TCLK
TS0 bit 1 TS0 bit 2
TS31 bit 5 TS31 bit 6TS31 bit 7 TS31 bit 8 TS0 bit 1 TS0 bit 2
TDATO
TOHM
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990267, Issue 3
302
PMC [ PMC-SIERRA, INC ]
