PM8611-BIAP PMC [PMC-Sierra, Inc], PM8611-BIAP Datasheet - Page 24

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

Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-2010883, Issue 2
Pin Name
JUST_REQ
JUST_REQ[1]
(continued)
OTPL
OTAIS
Type
Bidir
Tristate
Output
Tristate
Output
Pin
No.
K12
A8
D8
Function
Shared Bus Justification Request (JUST_REQ). The SBI Bus
Justification Request signal, JUST_REQ, is used to speed up, slow
down or maintain the minimal rate of a slave timed SBI device.
When the SBSLITE is configured to be connected to a physical
layer device, JUST_REQ is an input aligned with the incoming bus.
When the SBSLITE is configured to be connected to a link layer
device, JUST_REQ is an output aligned with the outgoing bus.
This active high signal, JUST_REQ, indicates negative timing
adjustments on the SBI bus when asserted high during the V3 or
H3 octet, depending on the tributary type. In response to this the
slave timed SBI device should send an extra byte in the V3 or H3
octet of the next frame along with a valid payload signal indicating
a negative justification.
This signal indicates positive timing adjustments on the
corresponding SBI bus when asserted high during the octet
following the V3 or H3 octet, depending on the tributary type. The
slave timed SBI device should respond to this by not sending an
octet during the V3 or H3 octet of the next frame along with a valid
payload signal indicating a positive justification.
For fractional rate links this signal is asserted high during any
available information byte to indicate to the slave timed SBI device
that the timing master device is able to accept another byte of data.
For every byte that this signal is asserted high the slave device is
expected to send a valid byte of data.
All timing adjustments from the slave timed device in response to
the justification request must still set the payload and payload
indicators appropriately for timing adjustments.
JUST_REQ is not used when configured for TelecomBus mode.
JUST_REQ is asserted or sampled on the rising edge of
SREFCLK.
Outgoing Tributary Payload (OTPL). This signal is used to
indicate tributary payload when configured for TelecomBus and is
held low when configured for an SBI336 bus.
OTPL is set high during valid VC11 and VC12 bytes of the
Outgoing bus. OTPL is set low for all transport overhead bytes,
high order path overhead bytes, fixed stuff column bytes and
tributary transport overhead bytes (V1,V2,V3,V4).
OTPL is updated on the rising edge of SREFCLK.
Outgoing Tributary Alarm Indication Signal (OTAIS). This signal
indicates tributaries in low order path AIS state for the Outgoing
TelecomBus and is held low when configured for an SBI336 bus.
OTAIS is set high when the tributary on the Outgoing bus is in AIS
state and is set low when the tributary is out of AIS state.
OTAIS is updated on the rising edge of SREFCLK.
SBSLITE™ Telecom Standard Product Data Sheet
Preliminary
23