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Multi-Service Access Device For Channelized Interfaces
Telecom Standard Product Data Sheet
Production
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990823, Issue 4
560
Normal operation occurs when the character alignment sub-block is in the SYNC state. 8B/10B
characters are extracted from the FIFO using the character alignment of the K28.5 character that
caused entry to the SYNC state. Mimic K28.5 characters at other alignments are ignored. The
receive data is constantly monitored for line code violations. If 5 or more LCVs are detected in a
window of 15 characters, the character alignment sub-block transitions to the HUNT state. It will
search all possible alignments in the receive data for the K28.5 character. In the mean time, the
original character alignment is maintained until a K28.5 character is found. At that point, the
character alignment is moved to this new location and the sub-block transitions to the SYNC
state.
14.2.2 Frame Alignment
The frame alignment sub-block monitors the data read from the FIFO buffer sub-block for the J0
byte. When the frame counter sub-block indicates the J0 byte position, a J0 character is expected
to be read from the FIFO. If a J0 byte is read out of the FIFO at other byte positions, a J0 byte
error counter is incremented. When the counter reaches a count of 3, the frame alignment sub-
block transitions to HUNT state. The next time a J0 character is read from the FIFO, the
associated read address is latched and the sub-block transitions back to the SYNC state. The J0
byte error counter is cleared when a J0 byte is read from the FIFO at the expected position.
14.2.3 Character Decode
The following tables show the extended 8B/10B maps used by the S/UNI-MACH48. The
extended character set allows the mapping of TelecomBus control bytes and signals into 8B/10B
control characters. The table is divided into two sections, one for each software configurable
mode of operation.
Table 45 Serial TelecomBus 8B/10B Control Character Decoding
Code Group
Name
Curr. RD-
abcdei fghj
Curr. RD+
abcdei fghj
Decoded Signals
Description
Multiplex Section Termination (MST) Mode
K28.5
001111 1010
110000 0101
IJ0J1=’b1, IPL = ‘b0
Transport frame alignment
K.28.4-
001111 0010
-
IPAIS=’b1’
High-order path AIS
High-Order Path Termination (HPT) Mode
K28.0-
001111 0100
-
IPL = ‘b0,
High-order path H3 byte,
no negative justification event
K28.0+
-
110000 1011
IPL = ‘b0
High-order path PSI byte, positive
justification event
K28.6
001111 0110
110000 1001
IJ1=’b1’, IPL = ‘b1
High-order path frame alignment