PM8611-BIAP PMC [PMC-Sierra, Inc], PM8611-BIAP Datasheet - Page 64

• Manufacturer Part Number: PM8611-BIAP
• Manufacturer: PMC [PMC-Sierra, Inc]

10.16.1 Outgoing SBI336S Translation
10.17 Outgoing SBI336 Timing Adapter
10.18 In-band Link Controller
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-2010883, Issue 2
This block translates the generic internal SBI format to the external SBI format. A control RAM
keeps the current configuration of the outgoing SBI bus(es) and the tributaries carried so that it
can perform the translation function.
Common to all tributaries is identification of the first C1 byte. There are unique mappings of the
8B/10B codes for the supported SBI bus link types: Asynchronous T1/E1, Synchronous (locked)
T1/E1, Transparent VT1.5/VT2, DS3/E3 and Fractional rate links. Much of the identification and
mapping of a link from serial SBI format is based on the OC1FP frame pulse and a tributaries
location relative to that C1 reference. In addition to the OC1FP identification this block identifies
multiframe alignment, valid payload, pointer movements for floating tributaries and timing
control for decoding from the 8B/10B serial SBI format.
The Outgoing SBI336 Timing Adapter, OSTA, provides a demultiplexing from a 77.76 MHz
SBI336 or TelecomBus to four outgoing 19.44 MHz SBI or TelecomBuses. The outgoing timing
adapter block also provides a transparent mode when the outgoing interface is already in 77.76
MHz SBI336 or TelecomBus format.
When the SBS is connected to a 19.44 MHz SBI link layer device the justification request signal,
JUST_REQ, is an output from the SBS and is aligned to the incoming bus. This block re-aligns
the internal justification request signal from the internal outgoing SBI336 frame alignment to the
incoming SBI frame alignment, marked by IC1FP. When the SBS is connected to a 19.44 MHz
SBI physical layer device or any 77.76 MHz SBI336 device, no re-alignment of the justification
request is required by this block.
In order to permit centralized control of distributed NSE/SBSLITE fabrics from the NSE
microprocessor interface (for applications in which NSEs are located on fabric cards, and
SBSLITEs are located on multiple line cards), an in-band signaling channel is provided between
the NSE and the SBSLITE over the Serial interface. Each NSE can control up to 32 SBSLITEs
which are attached by the LVDS links. The NSE/SBSLITE in-band channel is full duplex, but the
NSE has active control of the link.
The SBSLITE contains two independent In-Band Link Controllers. One ILC is connected to the
Working Transmit Serial LVDS Link and the other is connected to the Protection Transmit Serial
LVDS Link.
The in-band channel is carried in the first 36 columns of four rows of the SBI or TelecomBus
structure, rows 3, 6, 7 and 8. The overall in-band channel capacity is thus 36*4*64kb/s =
9.216Mb/s. Each 36 bytes per row allocated to the in-band signaling channel is its own in-band
message between the end points. Four bytes of each 36 byte inband message are reserved for end-
to-end control information and error protection, leaving 8.192Mb/s available for user data transfer
between the end points.
SBSLITE™ Telecom Standard Product Data Sheet
Preliminary
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