LAN9115_05 Datasheet, PDF (98/131 Pages) SMSC Corporation – Highly Efficient Single- Chip 10/100 Non-PCI Ethernet Controller

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Highly Efficient Single-Chip 10/100 Non-PCI Ethernet Controller
Datasheet
DESCRIPTION
Loopback operation Mode (LOOPBK). Selects the loop back operation modes for the MAC. This is
only for full duplex mode
1’b0: Normal: No feedback
1’b1: Internal: Through MII
In internal loopback mode, the TX frame is received by the Internal MII interface, and sent back to
the MAC without being sent to the PHY.
Note:
When enabling or disabling the loopback mode it can take up to 10µs for the mode change
to occur. The transmitter and receiver must be stopped and disabled when modifying the
LOOPBK bit. The transmitter or receiver should not be enabled within10µs of modifying the
LOOPBK bit.
Full Duplex Mode (FDPX). When set, the MAC operates in Full-Duplex mode, in which it can transmit
and receive simultaneously. In Full-Duplex mode, the heartbeat check is disabled and the heartbeat
fail status should thus be ignored.
Pass All Multicast (MCPAS). When set, indicates that all incoming frames with a Multicast destination
address (first bit in the destination address field is 1) are received. Incoming frames with physical
address (Individual Address/Unicast) destinations are filtered and received only if the address matches
the MAC Address.
Promiscuous Mode (PRMS). When set, indicates that any incoming frame is received regardless of
its destination address.
Inverse filtering (INVFILT). When set, the address check Function operates in Inverse filtering mode.
This is valid only during Perfect filtering mode.
Pass Bad Frames (PASSBAD). When set, all incoming frames that passed address filtering are
received, including runt frames, collided frames or truncated frames caused by buffer underrun.
Hash Only Filtering mode (HO). When set, the address check Function operates in the Imperfect
Address Filtering mode both for physical and multicast addresses
Reserved
Hash/Perfect Filtering Mode (HPFILT). When reset (0), the LAN9115 will implement a perfect
address filter on incoming frames according the address specified in the MAC address register.
When set (1), the address check Function does imperfect address filtering of multicast incoming
frames according to the hash table specified in the multicast hash table register.
If the Hash Only Filtering mode (HO) bit is set (1), then the physical (IA) are imperfect filtered too. If
the Hash Only Filtering mode (HO) bit is reset (0), then the IA addresses are perfect address filtered
according to the MAC Address register
Late Collision Control (LCOLL). When set, enables retransmission of the collided frame even after
the collision period (late collision). When reset, the MAC disables frame transmission on a late
collision. In any case, the Late Collision status is appropriately updated in the Transmit Packet status.
Disable Broadcast Frames (BCAST). When set, disables the reception of broadcast frames. When
reset, forwards all broadcast frames to the application.
Disable Retry (DISRTY). When set, the MAC attempts only one transmission. When a collision is
seen on the bus, the MAC ignores the current frame and goes to the next frame and a retry error is
reported in the Transmit status. When reset, the MAC attempts 16 transmissions before signaling a
retry error.
Reserved
Automatic Pad Stripping (PADSTR). When set, the MAC strips the pad field on all incoming frames,
if the length field is less than 46 bytes. The FCS field is also stripped, since it is computed at the
transmitting station based on the data and pad field characters, and is invalid for a received frame
that has had the pad characters stripped. Receive frames with a 46-byte or greater length field are
passed to the Application unmodified (FCS is not stripped). When reset, the MAC passes all incoming
frames to the host unmodified.
Revision 1.1 (05-17-05)
98
DATASHEET
SMSC LAN9115