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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
104
The S/UNI-ATLAS-3200 can be configured to have some of its counters roll over or saturate at
all ones. All per-PHY counts, the per-connection cell counts, non-compliant cell counts, and the
PM counts are configurable in this manner.
The Rollover_FIFO_EN bit in the Configuration field of the VC table controls whether the 32-bit
per-VC Cell counts saturate, or whether they generate Count Rollover FIFO entries when their
MSB is logic 1, and then reset their MSBs to 0. The Policing Rollover FIFO EN bit in the
Policing Configuration field performs this function for the non-compliant counts; The PHY
Policing Rollover_FIFO_EN bit in the PHY Policing RAM performs the same function for the
per-PHY non-compliant counts, as does the PHY Rollover_FIFO_EN bit in the Per-PHY Counter
Configuration register for the other per-PHY counts. The PM_Rollover_FIFO_EN bit in the PM
Configuration Field of the Internal PM table controls whether the Performance Management
counts generate Count Rollover FIFO entries. The Count Rollover FIFO is described in Section
10.16.
All per-PHY and per-VC counts have a Clear On Read option. If this bit is logic 1, then when the
microprocessor reads the counter value, the value is immediately set to zero. If the per-PHY or
per-VC Clear On Read register bit is logic 0, the counter value is not cleared when it is read, and
the value must be cleared by explicitly writing all zeros to that counter location.
In order to allow for a time-of-day billing mechanism, the S/UNI-ATLAS-3200 provides
Alternate Count fields for the general 32-bit counts. When the Alternate_Count bit in the Cell
Processor Configuration register is set to logic 1, the 32-bit cell counts in all VCs stop
incrementing, and the Alternate Counts are incremented instead. The cell counts may then be
read at leisure by the microprocessor. When the Alternate_Count bit is set to logic 0 again, the
counting reverts to the regular 32-bit counts, and the Alternate Counts may be read (and
presumably cleared) at leisure by the microprocessor.
One of the objectives of counting is to count, somewhere, every cell that arrives. Almost all cells
can be counted in the per-VC cell counts. However, cells that do not belong to any particular
connection (i.e. they do not search to a valid, active connection) cannot be counted per-VC.
These cells have their own per-PHY count, the Invalid VPI/VCI/PTI cell count. The only overlap
between this count and the per-VC counts is for cells with a reserved VCI or PTI. The
Cnt_Rsvd_VCI_PTI bit in the per-PHY count configuration register controls whether cells with
reserved VCI or PTI are counted in the Invalid VPI/VCI/PTI cell count.
10.9
Operations, Administration and Maintenance (OAM) Cell
Servicing
The S/UNI-ATLAS-3200 is capable of terminating and monitoring F4 and F5 segment and end-
to-end OAM flows. Complete processing of Fault Management cells is provided on all
connections. Performance Management is provided on a limited number of connections (512
simultaneous sessions in each direction are supported). Activate/Deactivate and Undefined OAM
cells are passed to the Microprocessor Cell Interface or to the Output Cell Interface for external
processing. Loopback cells are examined, and routed based on their Loopback Indication,
Loopback Location ID, and Source ID.