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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
191
XVPIVCI
If the XVPIVCI bit is logic 1, VPI/VCI translation is globally enabled. The ATM cell
VPI/VCI bytes can be replaced by the contents of the Translated VPI and Translated VCI
words of the VC Table. If the GVPIVCI bit is logic 0, the incoming VPI/VCI combination is
passed transparently.
Note that if the connection is F4 (ie. VPC, where the VCI field in the search key is coded as
all zeros), then the VCI is passed through transparently, and if the connection is at a UNI, the
translation of the GFC field is controlled by XGFC.
XPREPO
If the XPREPO bit is logic 1, substitution of prepend and postpend bytes is globally enabled.
Any prepend or postpend bytes of an ATM cell are replaced by the contents of the Translated
Pre/Po1 and Translated Pre/Po 2 words of the VC Table. If XPREPO is logic 0, prepend and
postpend bytes pass through transparently.
XHEC
If the XHEC bit is logic 1, the HEC field of an ATM cell is replaced by the contents of the
Translated HEC word of the VC Table. If GHEC is logic 0, the HEC field of an ATM cell is
passed transparently.
XUDF
If the XUDF bit is logic 1, the UDF field of an ATM cell is replaced by the contents of the
Translated UDF field in the VC Table. If GUDF is logic 0, the UDF field of an ATM cell is
passed transparently.
XGFC
If the XGFC bit is logic 1 and the connection belongs to a UNI, then the GFC field is
replaced by the top 4 bits of the Translated VPI field in the VC table. If XGFC is logic 0 and
the connection belongs to a UNI, the GFC field is passed through transparently. If the
connection belongs to an NNI, then this bit has no effect.
Cell_Info_to_UP
The Cell Info to UP bit allows the Microprocessor Cell Info Field to replace the two
Prepend/Postpends of a cell extracted to the Microprocessor Interface. This allows an
external microprocessor to immediately determine the reason a cell was routed to the
Microprocessor Cell Interface, the PHY it was on, and the VC Record that processed it.