PM3350 ELAN 8 X10
ELAN 8X10
DATA SHEET
PMC-970109
ISSUE 3
8 PORT ETHERNET SWITCH
DEVICE DATA
Introduction
The PM3350 ELAN 8x10 offers a complete system-level solution, integrating all
required elements (except packet-buffer/address-table memory and transceiver logic) in
a single high-density VLSI chip. It is a true single-chip managed switch; all the required
functions, including address learning/aging, management, RMON-level statistics
collection, spanning tree support and self-configuration, are performed by the ELAN
8x10 without need for external CPUs or logic. In addition, the functions required for
expandability are also integrated into the device.
The ELAN 8x10 is built around a RISC CPU based Switch Processor core, coupled with
a multi-channel DMA controller, MAC-layer interface logic, FIFOs, a PCI-based
expansion port and a flexible memory controller.
Switch Processor
An on-chip Switch Processor is primarily responsible for performing the Ethernet / IEEE
802.3 packet switching functions, and can switch packets arriving simultaneously from
the eight 10BaseT ports and the expansion port at full wire rates using address tables
that it creates and maintains in external local memory. Store-and-forward switching is
performed, allowing the Switch Processor to detect CRC, length and alignment errors
and reject bad packets. The Switch Processor also supports IEEE 802.3
group/functional address handling. Address aging, topology change updates, and
statistics collection are performed by the Switch Processor as well.
The Switch Processor unit allows the device to support high-level capabilities. In
addition, it implements the full IEEE 802.1d spanning-tree transparent bridging protocol,
which allows the ELAN 8x10 to act as a eight-port expandable learning bridge,
performing learning, filtering and redirection at full speed. Finally, the Switch Processor
can host an SNMP agent for powerful remote switch configuration and diagnostic
capabilities, allowing systems built around the ELAN 8x10 to be managed in-band using
standard management platforms. When additional switch devices are connected to the
ELAN 8x10 expansion port, the Switch Processors in all ELAN 8x10s intercommunicate
to transparently support a distributed SNMP MIB.
In host-based applications, the host CPU may bypass the on-chip SNMP agent to
communicate directly with the Switch Processor for configuration, control and
monitoring purposes.
Multichannel DMA Processor
The on-chip DMA Coprocessor contains eleven independent and concurrently operating
channels, one for each of the eight 10BaseT ports and three dedicated to the
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND PMC-SIERRA, INC. CUSTOMERS ONLY
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PMC [ PMC-SIERRA, INC ]
