
PM5317 SPECTRA-9953 Telecom Standard Product Data Sheet
Release
Proprietary and Confidential to PMC-Sierra, Inc., and for its customers’ internal use.
Document No.: PMC-2000741, Issue 5
118
14.17 Space Slot Interchange (SSI)
The SONET/SDH Space Slot Interchange (SSI) block grooms the SONET/SDH data stream by
performing STS-12 (STM-4) space switching. Any STS-12 (STM-4) can be switched to any
STS-12/STM-4 space slot.
14.18 8B/10B Encoder (T8TE)
The drop Data 8B/10B Encoder block (T8TE) constructs an 8B/10B character stream from an
incoming TelecomBus carrying an STS-12/STM-4 stream. A total of 16 T8TE blocks are
instantiated in the SPECTRA-9953 device.
The T8TE operates in one of two modes: multiplex section termination (MST) and high-order
path termination (HPT) mode. In MST mode, the upstream block is a multiplex section
terminator. It has identified transport frame boundaries. The first J0 byte (J0) On each
DD[x][7:0] STS-12 link is encoded by an 8B/10B control character. In HPT mode, the upstream
block is a high-order path terminator and has performed pointer processing to identify STS/AU
level pointer justification events. It has processed all the STS/VC3/VC4 path overhead bytes.
The H3 bytes in the absence of negative pointer justification events, the PSO byte in the
presence of positive pointer justification events may be encoded. Alternately, the J1 byte may
be encoded.
Table 13 shows the mapping of TelecomBus control bytes and signals into 8B/10B control
characters. The table is divided into three sections, one for each software configurable mode of
operation.
Table 13 Serial TelecomBus 8B/10B Character Mapping
Code
Group
Name
Curr. RD-
abcdei fghj
Curr. RD+
abcdei fghj
Encoded Signals
Description
Multiplex Section Termination (MST) Mode
K28.5
001111 101
110000 0101
IJ0 = ’b1
IPL = ‘b0
A1 #1
A1 #2
A1 #3
A1 #4
...
...
...
...
A1 #45
A1 #46
A1 #47
A1 #48
A1 #1
A1
A1 #2
A1 #3
A1 #4
A1 #5
A1 #6
A1 #7
A1 #8
A1 #9
A1 #10
A1 #11
A1 #12
A1 #13
A1 #14
A1 #15
A1 #16
AD1[7:0]/DD1[7:0]
A1 #18
A1 #17
A1 #25
A1 #24
A1 #20
A1 #19
A1 #21
A1 #22
A1 #23
A1 #27
A1 #29
A1 #31
A1 #26
A1 #28
A1 #30
A1 #32
A1 #33
A1 #35
A1 #37
A1 #39
A1 #34
A1 #36
A1 #38
A1 #40
A1 #41
A1 #42
A1 #43
A1 #44
A1 #45
A1 #47
A1 #48
A1 #46
STS-48c/AU-4-
16c
AD2[7:0]/DD2[7:0]
AD3[7:0]/DD3[7:0]
AD4[7:0]/DD4[7:0]
Order of
transmission
Order of
transmission