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PM7329 S/UNI-APEX-1K800
DATASHEET
PMC-2010141
ISSUE 2
ATM TRAFFIC MANAGER AND SWITCH
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
54
on the following address that was serviced. Since the polling is tied to the data
transfer, the WAN transmit interface is capable of mixing prepend enabled UL2
and Any-PHY slaves on the same bus with some external glue logic.
In UL2M, loop interface port selection is done via the 6 lower bits of the 12-bit
polling address bus, supporting up to 32 ports. WAN interface port selection is
done via the 3-bit polling address bus, supporting up to 4 ports.
Details of the polling algorithm for the loop and WAN interface can be found in
the loop port scheduler and WAN port scheduler section respectively.
The UL1M is effectively a UL2M without address polling, but retains the port
selection handshake. Hence a single external UL2S may be connected to the
S/UNI-APEX-1K800 UL1M transmit interface. Specific only to the WAN UL1M
mode, port address is presented with a programmable value , giving the option of
port sparing.
In slave mode, the transmit interface operates as a single port UTOPIA L2
receive slave port. The 6 lower bits of the 12-bit loop polling address, or the
entire 3 bits of the WAN polling address become inputs. The loop interface can
be configured to respond to any port identifier from 0 to 31. The WAN interface
can be configured to respond to any port identifier from 0 to 3.
Table 5
- Number of Ports Supported, Transmit Interface
Mode
Loop (8 bit)
Loop (16 bit)
WAN (8 bit)
WAN (16bit)
Any-PHY Master
128
128
4
4
UTOPIA L2
Master
32
32
4
4
UTOPIA L1
Master
1 (no sparing)
1 (no sparing)
1 (4 sparing)
1 (4 sparing)
UTOPIA L2 Slave
1 of 32
1 of 32
1 of 4
1 of 4
10.2 Loop Port Scheduler
The S/UNI-APEX-1K800 loop port scheduler provides weighted interleaved
round robin scheduling of up to 128 Any-PHY addresses. To achieve fairness
among the 128 ports and to avoid wasted polling opportunities, the selection of
what ports to poll is based on what ports have transmit data queued and have a
high probability of being able to accept the cell.
The scheduler has 128 polling sequences and 8 different weighting groups.
Software configures the number of polling sequences a port should participate in