S/UNI®-ATLAS-3200 Telecom Standard Product Data Sheet
Preliminary
The destination of each OAM cell depends on the type of OAM cell and whether or not the
S/UNI-ATLAS-3200 is the end-point for that particular OAM flow. If the S/UNI-ATLAS-3200 is
not an end-point, the OAM cells are routed to the same destination as user cells, with the
exception of Loopback cells. If the S/UNI-ATLAS-3200 is an end point, the default
configuration terminates and processes all OAM cells except APS, System Management,
Activate/Deactivate and Undefined OAM cells, which may optionally be routed to either the
Output Cell Interface, or the Backward Cell Interface, or the Microprocessor Cell Interface. End-
to-end points are treated as also being segment end-points as well for the purposes of routing
these cells, to aid in localization of problems. The cell information fields prepended to cells sent
to the MCIF or BCIF is intended as an aid to processing these cells.
Parent Loopback OAM cells will have their Loopback Location ID examined. Depending on the
setting of the Loopback Routing bits in the Configuration field of the VC table, loopback cells
may be routed to the Backwards Cell Interface, with their Loopback Indication bit cleared and the
local Loopback Location Identifier encoded in their Loopback Location ID field. The Source ID
is not changed.
Returned Loopback OAM cells will have their Source ID examined. Depending on the setting of
the Loopback Routing bits in the Configuration field of the VC Table, Returned Loopback cells
may be dropped and routed to the microprocessor if the Source ID of the cell matches the local
Loopback ID programmed into the CP Loopback ID registers. Depending on the setting of the
Rtd_LB_to_UP_at_End bit in the CP Routing Configuration register, Returned Loopback cells
may be routed to the microprocessor at flow end points irrespective of the Source ID.
10.17.1 Output Backward OAM Cell Interface
The Output Backwards Cell Interface is an extended cell length 16-bit, 52 MHz UTOPIA Level 1
Rx Slave “SCI-PHY” interface. Generated RDI and Backwards Reporting cells, along with
Loopback cells, use this interface to access the opposite direction BCIF. A 16-cell FIFO is
provided on the Output BCIF, and another 16 cell in the Input BCIF, to facilitate these transfers.
The default configuration is shown in Figure 20
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990553, Issue 4
134
PMC [ PMC-SIERRA, INC ]
