NetBSD/share/man/man4/ec.4

109 lines
4.6 KiB
Groff

.\" $NetBSD: ec.4,v 1.5 1999/01/14 00:16:42 sommerfe Exp $
.\"
.\" Copyright (c) 1997 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
.\" NASA Ames Research Center.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\" must display the following acknowledgement:
.\" This product includes software developed by the NetBSD
.\" Foundation, Inc. and its contributors.
.\" 4. Neither the name of The NetBSD Foundation nor the names of its
.\" contributors may be used to endorse or promote products derived
.\" from this software without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.Dd October 20, 1997
.Dt EC 4
.Os NetBSD
.Sh NAME
.Nm ec
.Nd device driver for 3Com Etherlink II (3c503) Ethernet cards
.Sh SYNOPSIS
.Cd "ec0 at isa? port 0x250 iomem 0xd8000 irq 9"
.Sh DESCRIPTION
The
.Nm
device driver supports 3Com Etherlink II (3c503) Ethernet cards.
.Sh MEDIA SELECTION
The Etherlink II supports two media types on a single card. All support
the AUI media type. The other media is either BNC or UTP behind a
transciever. Software cannot differentiate between BNC and UTP cards.
.Pp
To enable the AUI media, select the
.Em 10base5
or
.Em aui
media type with
.Xr ifconfig 8 's
.Sq media
directive. To select the other media (BNC or UTP), select the
.Em 10base2
or
.Em bnc
media type.
.Sh DIAGNOSTICS
.Bl -diag
.It "ec0: wildcarded IRQ is not allowed"
The IRQ was wildcarded in the kernel configuration file. This is not
supported.
.It "ec0: invalid IRQ <n>, must be 3, 4, 5, or 9"
An IRQ other than the above listed IRQs was specified in the kernel
configuration file. The Etherlink II hardware only supports the
above listed IRQs.
.It "ec0: failed to clear shared memory at offset <off>"
The memory test was unable to clear shared the interface's shared memory
region. This often indicates that the card is configured at a conflicting
.Em iomem
address.
.It ec0: warning - receiver ring buffer overrun
The DP8390 Ethernet chip used by this board implements a shared-memory
ring-buffer to store incoming packets.
The 3c503 usually has only 8k bytes of shared memory. This is only
enough room for about 4 full-size (1500 byte) packets. This can
sometimes be a problem, especially on the original 3c503, because
these boards' shared-memory access speed is quite slow; typically only
about 1MB/second. The overhead of this slow memory access, and the
fact that there is only room for 4 full-sized packets means that the
ring-buffer will occassionally overrun. When this happens, the board
must be reset to avoid a lockup problem in early revision 8390's.
Resetting the board causes all of the data in the ring-buffer to be
lost, requiring it to be retransmitted/received, congesting the board
further. Because of this, maximum throughput on these boards is only
about 400-600k per second.
.Pp
This problem is exasperated by NFS because the 8bit boards lack
sufficient memory to support the default 8k byte packets that NFS and
other protocols use as their default. If these cards must be used
with NFS, use the NFS -r and -w options in /etc/fstab to limit NFS's
packet size. 4096k byte packets generally work.
.El
.Sh SEE ALSO
.Xr ifmedia 4 ,
.Xr intro 4 ,
.Xr isa 4 ,
.Xr ifconfig 8