ORT8850H AGERE [Agere Systems], ORT8850H Datasheet - Page 28

• Manufacturer Part Number: ORT8850H
• Description: Field-Programmable System Chip (FPSC) Eight-Channel x 850 Mbits/s Backplane Transceiver
• Manufacturer: AGERE [Agere Systems]

ORCA ORT8850 FPSC
Eight-Channel x 850 Mbits/s Backplane Transceiver
Backplane Transceiver Core Detailed
Description
The incoming data from the HSI (also referred to as
CDRM850) can be separated into four STS-12 chan-
nels (A, B, C, and D) per slice. Thus, there are STS-12
channels AA to AD from slice A of the STM and STS-
12 channels BA to BD of slice B. These streams can be
frame-aligned in the following patterns: in STS-48
mode, all four STS-12s of each STM slice are aligned
with each other (i.e., AA, AB, AC, AD). Optionally, in
STS-48 mode, all eight STS-12s (STMs A and B) can
be aligned (to allow hitless switching at the STS-48
level). Multiple devices can be aligned to enable STS-
192 or higher modes. Streams can also be aligned on a
twin STS-12 basis. There is also a provision to allow
certain streams to be disabled (i.e., not producing inter-
rupts or affecting synchronization). These streams can
be enabled at a later time without disrupting other
streams. If the selected stream needs to be a part of a
bigger group (i.e., STM A), then either the entire group
must be resynched or the affected stream must have
been in the correct mode (i.e., align all STM A) when
the initial synchronization was performed. As long as
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STM SLICE A
STM SLICE B
Figure 8. Interconnect of Streams for FIFO
Alignment
(continued)
STREAM AA
STREAM AB
STREAM AC
STREAM AD
STREAM BA
STREAM BB
STREAM BC
STREAM BD
STS-12
STS-12
STS-12
STS-12
STS-12
STS-12
STS-12
STS-12
SYNC
FIFO
5-8577 (F)
all four streams in STM A are in the correct mode when
synchronization takes place, then those streams may
be enabled or disabled without affecting synchroniza-
tion.
These streams can be frame-aligned in the patterns
shown in Figure 10, Figure 9, and Figure 11.
STM A S tream D
STM B Stream A
STM A Stream C
STM B Stream B
S TM B Stream C
S TM B S tream D
S TM B S tream D
STM A Stream B
S TM A Stream A
S TM B Stream D
STM A Stream B
STM B Stream A
STM A Stream B
STM B Stream A
Figure 10. Example of Intra-STM Alignment
Figure 11. Example of Twin STS-12 Stream
STM A Stream A
STM B Stream B
STM A Stream A
STM B Stream B
Figure 9. Example of Inter-STM Alignment
S TM A S tream D
S TM A S tream D
S TM B S tream C
S TM B S tream C
S TM A S tream C
S TM A S tream C
TWINS ALIGNMENT OF STREAMS A AND C
ALL 8 ALIG N M E NT O F STM A A ND STM B
ALL 4 ALIG N M E NT O F STM A A ND STM B
Alignment
Agere Systems Inc.
August 2001
STM B Stream A
STM B Stream A
STM B Stream B
STM B Stream C
STM B Stream D
STM A Stream B
STM B S tream B
S TM A Stream D
STM A S tream A
STM B S tream D
S TM A S tream C
S TM A S tream D
S TM B S tream C
S TM B S tream D
S TM A S tream C
S TM A S tream D
STM A Stream A
STM A Stream B
STM B Stream A
STM B Stream B
STM A Stream A
STM A Stream B
Data Sheet
S TM A Stream C
STM B Stream C
t
0
t
0
0673(F)
t
t
0
1
0674
0675
t
1