FBFM2112F897CSLJLS View Datasheet(PDF) - Intel

Part Name

Description

Manufacturer

FBFM2112F897CSLJLS

Intel® FM2112 24-Port 10G/1G Ethernet Switch Chip

Intel 

Intel® FM2112 24-Port 10G/1G Ethernet Switch Chip Data Sheet

3.1.6.1

3.1.6.2

The FM2112 implements a standard 10 Gigabit Ethernet MAC and/or a

standard 1G full duplex MAC (SGMII), and in addition supports some

optional proprietary and/or pre-standard implementations. The

supported specifications are:

• IEEE 802.3ae (10G MAC)

• IEEE 802.3z (SGMII MAC)

The MAC layer performs:

• Frame length enforcement

• CRC checking on ingress and CRC checking and generation on Egress

• Frame padding

• MIB counters (described in the frame control section)

• VLAN tagging (described in VLAN section)

• Priority regeneration (described in congestion management)

• MAC control frame trapping and generation

• Special support for proprietary routing applications

Frame Length, Errors and Trapping

The MAC supports the following frame lengths, and has specific

counters for their bins:

• Standard Ethernet frames - 64 bytes to 1522 bytes

• Jumbo frames - up to 10240 bytes

• Small frames - A minimum frame size configuration that can be set as low as 32

bytes. However, the system must not go above the max frame rate of the FM2112.

The CRC of all incoming frames is checked. In addition on Egress, after

queuing and before any tagging, the CRC is checked again, to catch

soft errors. Finally, the CRC may be regenerated on Tx if a tag is added

or removed. In the event of an error in cut-through mode, the CRC may

be forced bad.

Padding:

• If the actual frame length is below specified minimum frame length, and the frame

is not discarded, it is padded to the minimum frame length before transmission.

• If a length of a legal frame is reduced below the minimum frame length because a

VLAN tag was stripped, then it is padded to the minimum frame length.

Flow Control

{Described in registers Table 157 through Table 159}

The FM2112 is fully compliant with the “Pause” specification of IEEE

802.3-2002 Clause 31 and Annex 31B, also published as IEEE 802.3x.

At the link level the following aspects of “Pause” are configurable:

• Whether the pause feature is on

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