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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
253
13.3 Telecom DROP Bus Interface Timing
Figure 62 shows the function of the various telecom DROP bus signals in AU3
mode. Data on LDDATA[7:0] is sampled on the rising edge of LREFCLK. The
bytes forming the three STS-1 synchronous payload envelopes are identified
when the LDPL signal is high. In this diagram, a negative stuff event is shown
occurring on STS-1 #2 and a positive stuff event on STS-1 #3. The LDC1J1V1
signal pulses high, while LDPL is set low, to mark the C1 byte of the first STS-1
in every frame of the STS-3 transport envelope. The LDC1J1V1 signal is high
when the LDPL signal is high to mark every J1 byte of each of the three STS-1
SPEs. The bytes forming the various tributary synchronous payload envelopes
are identified by the LDTPL when set high. The LDV5 signal pulses high to mark
the V5 bytes of each outgoing tributaries. LDTPL and LDV5 are invalid when
LDPL is set low. The three STS-1 SPEs can each have different alignments to
the STS-3 transport envelope and the alignment is changing for two of the STS-1
SPEs (STS-1 #2 and #3) due to the pointer justification events shown.
Figure 62
- Telecom DROP Bus Timing - STS-1 SPEs / AU3 VCs
LDPL
LREFCLK
LDC1J1
LDV5
INVALID
INVALID
IV
IV
LDTPL
INVALID
INVALID
IV
IV
STS-1 #1 SPE J1 byte
LDDATA[7:0]
A1 A1 A2 A2 A2 C1 C1 C1
A1
H1 H1 H2 H2 H2 H3
H3
H1
Negative stuff for STS-1 #2
SPE which happens to
carry a non-final H4 byte
V5 byte as marked by OTV5
Positive stuff for STS-1 #3 SPE
J1
H4 Vx
V5
Any V1 - V4 byte
TU#1, STS-1 #1
Last H4 byte in
tributary multiframe
H4
C2
G1