LNC(4) BSD/i386 Kernel Interfaces Manual LNC(4)NAMElnc — AMD Am7900 LANCE and Am79C9xx PCnet Ethernet interface driver
SYNOPSIS
device lncDESCRIPTION
The lnc driver provides support for the AMD family of Lance/PCnet Ether‐
net NICs including the Am7990 and Am79C960.
The lnc driver also supports PCnet adapters based on the AMD 79C9xx fam‐
ily of chips, which are single-chip implementations of a LANCE chip and a
DMA engine. This includes a superset of the PCI bus Ethernet chip sets
supported by the pcn(4) driver. The lnc driver treats all of these PCI
bus Ethernet chip sets as an AMD Am79C970 PCnet-PCI and does not support
the additional features like the MII bus and burst mode of AMD Am79C971
PCnet-FAST and greater chip sets. Thus the pcn(4) driver should be pre‐
ferred for the latter.
The lnc driver supports reception and transmission of extended frames for
vlan(4). Selective reception of multicast Ethernet frames is provided by
a 64-bit mask; multicast destination addresses are hashed to a bit entry
using the Ethernet CRC function.
HARDWARE
PCI
The PCI bus Ethernet chip sets supported by the lnc driver are:
· AMD Am53C974/Am79C970/Am79C974 PCnet-PCI
· AMD Am79C970A PCnet-PCI II
· AMD Am79C971 PCnet-FAST
· AMD Am79C972 PCnet-FAST+
· AMD Am79C973/Am79C975 PCnet-FAST III
· AMD Am79C976 PCnet-PRO
· AMD Am79C978 PCnet-Home
The lnc driver supports the following media types with these chip sets:
autoselect Enable autoselection of the media type.
10baseT/UTP Select UTP media.
10base5/AUI Select AUI/BNC media.
The following media option is supported with these media types:
full-duplex Select full duplex operation.
Note that unlike the pcn(4) driver, the lnc driver does not support
selecting 100Mbps (Fast Ethernet) media types.
For further information on configuring media types and options, see
ifconfig(8).
DIAGNOSTICS
lnc%d: overflow More packets came in from the Ethernet than there was
space in the LANCE receive buffers. Packets were missed.
lnc%d: receive buffer error The LANCE ran out of buffer space, packet
dropped.
lnc%d: lost carrier The Ethernet carrier disappeared during an attempt
to transmit. The LANCE will finish transmitting the current packet, but
will not automatically retry transmission if there is a collision.
lnc%d: excessive collisions, tdr %d The Ethernet was extremely busy or
jammed, outbound packets were dropped after 16 attempts to retransmit.
TDR is the abbreviation of "Time Domain Reflectometry". The optionally
reported TDR value is an internal counter of the interval between the
start of a transmission and the occurrence of a collision. This value
can be used to determine the distance from the Ethernet tap to the point
on the Ethernet cable that is shorted or open (unterminated).
lnc%d: dropping chained buffer A packet did not fit into a single
receive buffer and was dropped. Since the lnc driver allocates buffers
large enough to receive maximum sized Ethernet packets, this means some
other station on the LAN transmitted a packet larger than allowed by the
Ethernet standard.
lnc%d: transmit buffer error The LANCE ran out of buffer space before
finishing the transmission of a packet. If this error occurs, the driver
software has a bug.
lnc%d: underflow The LANCE ran out of buffer space before finishing the
transmission of a packet. If this error occurs, the driver software has
a bug.
lnc%d: controller failed to initialize Driver failed to start the LANCE.
This is potentially a hardware failure.
lnc%d: memory error RAM failed to respond within the timeout when the
LANCE wanted to read or write it. This is potentially a hardware fail‐
ure.
lnc%d: receiver disabled The receiver of the LANCE was turned off due to
an error.
lnc%d: transmitter disabled The transmitter of the LANCE was turned off
due to an error.
SEE ALSOarp(4), ifmedia(4), intro(4), netintro(4), pcn(4), vlan(4), ifconfig(8)HISTORY
The lnc driver first appeared in FreeBSD 2.2, it was replaced in
DragonFly 1.5 with the le(4) driver from FreeBSD 6.1 which was in turn
ported from NetBSD. The NetBSD driver was derived from the le(4) driver
in 4.4BSD.
AUTHORS
The lnc driver was ported to FreeBSD by Marius Strobl
⟨marius@FreeBSD.org⟩ and later ported to DragonFly by Bill Marquette
⟨bill.marquette@gmail.com⟩.
BSD July 7, 2006 BSD
