PM8610-BIAP PMC [PMC-Sierra, Inc], PM8610-BIAP Datasheet - Page 74

• Manufacturer Part Number: PM8610-BIAP
• Description: SBS Telecom Standard Product Data Sheet Preliminary
• Manufacturer: PMC [PMC-Sierra, Inc]

10.4.2
10.5
10.6
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-2000168, Issue 3
The Connection Memory sub-block contains two pages of mapping configuration, page 0 and
page 1. One page is designated the active page and the other the stand-by page. Selection
between which page is to be active and which is to be stand-by is controlled by the ICMP signal
(for the IMSU) and OCMP signal (for the OMSU). The Connection Memory sub-block samples
the value on the ICMP signal at the C1 byte position as defined by the incoming frame pulse
signal, IC1FP. The Connection Memory sub-block samples the value on the OCMP signal at the
C1 byte position as defined by the receive serial interface frame pulse signal, RC1FP. Swaps
between the active/standby status of the two pages are synchronized to the first A1 byte of the
next frame or multiframe. This arrangement allows all devices in a cross-connect system to be
updated in a coordinated fashion. Consequently, DS0 streams or tributaries not being assigned
new positions are unaffected by page swaps.
The CMP input signals can be overridden by register configuration or by the SBI336S inband link
channel.
CAS Merging
The Channel Associated Signaling Merge blocks, ICASM and OCASM, insert the CAS signaling
information into the SBI bus on a tributary basis. CAS signaling channels within the SBI bus are
constructed out of the available CAS bits for T1 and E1 SBI tributaries that are enabled for CAS
signaling. The resulting CAS signaling channel replaces the octets of the SBI bus where the new
CAS signaling is to be inserted. This block adds one T1 multiframe (24 frames) or one E1
multiframe (16 frames) of latency to the CAS bits.
Incoming SBI336 Tributary Translator
The Incoming SBI336 Tributary Translator block, ISTT, translates all SBI336 timing and
Channel Associated Signaling information for all tributaries into SBI336S format. The output
from this block is a 77.76 MHz SBI336 stream with all tributaries and control signals encoded
into an internal format that closely resembles the serial SBI336S format.
This block translates all tributary types into a form that is easy for the 8B/10B encoder to handle
in a more generic form. A control RAM keeps the current configuration for each of the incoming
SBI bus tributaries 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 and SBI336 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 into serial SBI format is based on the C1 frame pulse and
a tributaries location relative to that C1 pulse. In addition to the C1FP identification this block
identifies multiframe alignment, valid payload, pointer movements for floating tributaries and
timing control for encoding into the 8B/10B serial SBI format.
This block is transparent in TelecomBus mode.
Connection Memory
SBS Telecom Standard Product Data Sheet
Preliminary
74