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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
66
The S/UNI-ATLAS-3200 input interface must behave as a Tx PHY layer device on the UTOPIA
bus. As a PHY layer device, it responds with the appropriate cell available (buffer) status when a
channel address is on the bus, TPU_ADDR. Additionally, when the ATM layer device engages a
transfer, the S/UNI-ATLAS-3200 must respond by accepting cell for the channel that has been
selected. The TxPhy block, assisted by the SDQ (see below) performs these functions. The TxPhy
configuration registers may be found in Section 11.7.
The S/UNI-ATLAS-3200 output interface must behave as a Tx Link Layer device on the
UTOPIA bus. As a Link Layer device, it controls the address bus, TLU_ADDR, in order to poll
the PHY to obtain cell available (buffer) status. Polling is performed in a weighted round-robin
fashion controlled by a software-configurable calendar. Once the Cell Available information has
been collected through polling, port selection is performed using the same calendar. The calendar
is programmed via the TxLink block’s Calendar Address and Data Register, and is described in
Section 10.1.7. The TxLink block can map internal PHY addresses to different external PHY
addresses via a user-programmable port map, as described in Section 10.1.6. The TxLink block,
assisted by the SDQ (see below) performs these functions. The TxLink configuration registers
may be found in Section 11.10.
10.1.3 Ingress Mode with POS-PHY Level 3 Signaling
In this configuration, the S/UNI-ATLAS-3200 receives traffic from a PHY, and transmits traffic
to a traffic manager. This traffic consists of variable-length packets, transferred using POS-PHY
Level 3 signaling.