PM8611 Datasheet, PDF (61/292 Pages) PMC-Sierra, Inc – SBSLITE™ Telecom Standard Product Data Sheet Preliminary

SBSLITE™ Telecom Standard Product Data Sheet
Preliminary
10.15.3 Character Alignment Block
Character alignment locates character boundaries in the incoming 8B/10B data stream. The
character alignment algorithm may be in one of two states, in-character-alignment state and out-
of-character-alignment state. The two states of the character alignment algorithm is shown in
Figure 8.
When the character alignment state machine is in the out-of-character-alignment state, it
maintains the current alignment, while searching for a C1FP character. If it finds the C1FP
character it will re-align to the C1FP character and move to the in-character-alignment state. The
C1FP character is found by searching for the 8B/10B C1FP character, K28.5+ or K28.5-,
simultaneously in ten possible bit locations. While in the in-character-alignment state, the state
machine monitors LCVs. If 5 or more LCVs are detected within a 15 character window the
character alignment state machine transitions to out-of-character-alignment state. The special
characters listed in Table 21 and Table 22 are ignored for LCV purposes. Upon return to in-
character-alignment state the LCV count is cleared.
Figure 8 Character Alignment State Machine
5-in-15 LCVs
out-of-
character-
alignment
in-
character-
alignment
Found C1FP Character
10.15.4 Frame Alignment
Frame alignment locates SBI or TelecomBus frame and multiframe boundaries in the incoming
8B/10B data stream. The frame alignment state machine may be in one of two states, in-frame-
alignment state and out-of-frame-alignment state. Each SBI336S frame is 125 µS in duration.
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
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Document ID: PMC-2010883, Issue 2