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S/UNI-ATLAS-3200 Telecom Standard Product Data Sheet
Preliminary
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990553, Issue 4
106
If the CC_Activate_Segment bit is a logic 1, and no user cells have been transmitted within a 1.0
second (nominal) window, a segment CC cell is generated and sent to the Output Cell Interface.
The forced generation of CC cells (independent of the flow of user cells) at one second (nominal)
intervals is enabled when the CC_Activate_Segment bit is logic 1 and the ForceCC register bit is
logic 1. If the ForceCC register bit is logic 0, then the generation of CC cells is dependent on the
flow of user cells. Regardless of the state of the CC_Activate_Segment bit, if no user cells or
segment CC cells have been received within a 3.5 +/- 0.5 sec window, the CC_Alarm_Segment
status bit is set. If the connection FM_Interrupt_Enable bit is set, a globally maskable interrupt
will be asserted at the change of state of the segment CC alarm. The Segment CC alarm is cleared
upon the reception of the first user or Segment CC cell.
If the S/UNI-ATLAS-3200 is configured as a segment end-point, and the AUTO_RDI and
CC_AIS_RDI bits of the OAM Configuration field is set, a segment RDI cell is generated once
per second into the reverse direction while the segment CC alarm is declared. In addition, if the
AUTO_AIS bit is logic 1, then an ETE AIS cell is generated once per second while segment CC
alarm is declared.
If the S/UNI-ATLAS-3200 is not configured as a segment end point, then if the Segment_Flow
bit is logic 1, the AUTO_AIS register bit is set, and the CC_AIS_RDI bit is set in the OAM
Configuration field of the VC table, a segment AIS cell is generated once per second while
Segment CC alarm is declared and Segment AIS alarm is not declared.
When AIS cells are generated by the S/UNI-ATLAS-3200 due to the AUTO_AIS function, the
per-PHY AIS generation bits, or the per-VC Send_AIS bits, the Generated_Defect_Type[7:0]
field in the VC table is used for the defect type, and the Defect Location register fields are used
for the defect location.
When F5 AIS cells are generated due to F4 AIS, the defect location and type of the F4 AIS cell
that caused the alarm are sent. Similarly, when F4 Ete AIS cells are sent as a result of reception
of Segment AIS cells (via the APSx function) the Defect Location and Type of the received
Segment AIS cell is used.
For each segment OAM capability described above, the same capability exists for the End-to-
End.
The S/UNI-ATLAS-3200 also supports the generation of F5 AIS and RDI cells when associated
F4 connections, which are terminated, enter the AIS alarm state. This is described in detail in
section 10.10.
The S/UNI-ATLAS-3200 may be configured on a per-PHY basis to output AIS or RDI cells (or
both) on all connections whose PHYID matches those set in a programmable register. The Per-
PHY RDI Cell Generation Control and Per-PHY AIS Cell Generation Control registers control
the generation of RDI and AIS cells on entire PHYs at once. When the PHY AIS bits are set, end-
to-end cells (and, if Segment_Flow is logic 1, segment AIS cells) are sent once per second, except
at flow end points. When the PHY RDI bits are set, RDI cells will be sent once per second in the
reverse flow direction on all connections which are segment or end-to-end points. In the case of a
segment end point, one segment RDI and one end-to-end AIS cell will be sent per second, if both
the PHY AIS and PHY RDI bits are set.