PM7341 Datasheet, PDF (73/413 Pages) PMC-Sierra, Inc – S/UNI INVERSE MULTIPLEXING FOR ATM, 84 LINKS

PRELIMINARY
INVERSE MULTIPLEXING OVER ATM
DATASHEET
PMC-2000223
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PM7341 S/UNI-IMA-84
INVERSE MULTIPLEXING OVER ATM
10.1.2 Receive Any-PHY/UTOPIA Slave (RXAPS)
In the receive direction, each S/UNI-IMA-84 transmits cells on an Any-
PHY/UTOPIA L2 compatible interface operating at clock rates up to 52 MHz and
supporting 16-bit and 8-bit wide cells. The S/UNI-IMA-84 operates as a bus
slave.
In all modes, an optional prepend is allowed on the bus. This prepend will
always be set to zero and has no significance to the S/UNI IMA-84 but is
provided for interoperability.
10.1.2.1 UTOPIA Level 2 Multi-Address Slave Mode
In UTOPIA Level 2 Multi-Address Slave mode, the S/UNI-IMA-84 operates as a
31 port multi-PHY with each virtual PHY stored in its own FIFO. UTOPIA L2
Mode limits the S/UNI-IMA-84 to 31 IMA groups or TC links. A 4-bit configuration
register, RCAEN, controls the response to polling the individual channels within
this group of 31 ports. Setting RCAEN[0] enables addresses 0 through 7, and
RCAEN[3] enables addresses 24 through 30. This is typically used to allow more
than one slave device to share the Receive UTOPIA master bus. When polled,
the Receive Packet Available (RPA) output indicates whether there is at least one
cell available for transfer from the polled link. Upon selection, the interface
handles data pausing anywhere in the middle of a cell transfer.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
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