Linux	Ethernet-Howto
  Paul Gortmaker, Editor.
  v2.3,	11/02/95

  This is the Ethernet-Howto, which is a compilation of	information
  about	which ethernet devices can be used for Linux, and how to set
  them up. It hopefully	answers	all the	frequently asked questions about
  using	ethernet cards with Linux. Note	that this Howto	is focused on
  the hardware and low level driver aspect of the ethernet cards, and
  does not cover the software end of things. See the NET2-Howto	for that
  stuff.

  1.  Introduction


  The Ethernet-Howto covers what cards you should and shouldn't	buy; how
  to set them up, how to run more than one, and	other common problems
  and questions. It contains detailed information on the current level
  of support for all of	the most common	ethernet cards available.  It
  does not cover the software end of things, as	that is	covered	in the
  NET-2	Howto. Also note that general non-Linux	specific questions about
  Ethernet are not (or at least	they should not	be) answered here. For
  those	types of questions, see	the excellent amount of	information in
  the comp.dcom.lans.ethernet FAQ. You can FTP it from dorm.rutgers.edu
  in the directory /pub/novell/info_and_docs/

  This present revision	covers kernels up to and including v1.1.91

  The Ethernet-Howto is	edited and maintained by:

       Paul Gortmaker, Paul.Gortmaker@anu.edu.au


  The primary source of	the information	for the	Ethernet-Howto is from:

       Donald J. Becker, becker@cesdis.gsfc.nasa.gov


  who we have to thank for writing the vast majority of	ethernet card
  drivers that are presently available for Linux. He also is the
  original author of the NFS server too. Thanks	Donald!	We owe ya one!
  :-)

  Net-surfers may wish to check	out the	following URL:

  Donald Becker
  (http://cesdis.gsfc.nasa.gov/pub/people/becker/whoiam.html)


  1.1.	Using the Ethernet-Howto


  As this guide	is getting bigger and bigger, you probably don't want to
  spend	the rest of your afternoon reading the whole thing. And	you
  don't	have to	read it	all. If	you haven't got	an ethernet card, then
  you will want	to start with ``What card should I buy...''  to	see what
  you should buy, and what you should avoid. If	you have already got an
  ethernet card, but are not sure if you can use it with Linux,	then you
  will want to read ``Vendor Specific...''  which contains specific
  information on each manufacturer, and	their cards. If	you are	having
  trouble with your card, then you will	want to	read the specific
  information about your card mentioned	above, and the troubleshooting
  information in ``the FAQ section''.  If you are interested in	some of
  the technical	aspects	of the device drivers, then you	can find that
  information in ``Technical Information''

  1.2.	Disclaimer and Copyright


  This document	is not gospel. However,	it is probably the most	up to
  date info that you will be able to find. Nobody is responsible for
  what happens to your hardware	but yourself. If your ethercard	or any
  other	hardware goes up in smoke (...nearly impossible!)  we take no
  responsibility. ie. THE AUTHORS ARE NOT RESPONSIBLE FOR ANY DAMAGES
  INCURRED DUE TO ACTIONS TAKEN	BASED ON THE INFORMATION INCLUDED IN
  THIS DOCUMENT.

  This document	is Copyright (c) 1994 by Donald	Becker and Paul
  Gortmaker. Permission	is granted to make and distribute verbatim
  copies of this manual	provided the copyright notice and this
  permission notice are	preserved on all copies.

  Permission is	granted	to copy	and distribute modified	versions of this
  document under the conditions	for verbatim copying, provided that this
  copyright notice is included exactly as in the original, and that the
  entire resulting derived work	is distributed under the terms of a
  permission notice identical to this one.

  Permission is	granted	to copy	and distribute translations of this
  document into	another	language, under	the above conditions for
  modified versions.

  If you are intending to incorporate this document into a published
  work,	please contact me, and I will make an effort to	ensure that you
  have the most	up to date information available. In the past, out of
  date versions	of the Linux howto documents have been published, which
  caused the developers	undue grief from being plagued with questions
  that were already answered in	the up to date versions.


  1.3.	Mailing	Lists and the Linux Newsgroups



  If you have questions	about your ethernet card, please READ this
  document first. You may also want to join the	NET channel of the
  Linux-activists mailing list by sending mail to

       linux-activists-request@niksula.hut.fi


  with the line

       X-Mn-Admin: join	NET


  at the top of	the message body (not the subject). If you want	to learn
  how to use the mailing channels, then	send an	empty message to the
  above	address, and you will get an instruction manual	sent back to you
  in a few hours. However, it is worth noting that the NET channel is
  primarily used for discussion	of the networking code,	and you	may not
  see much discussion about a particular driver.

  Furthermore keep in mind that	the NET	channel	is for development
  discussions only. General questions on how to	configure your system
  should be directed to	comp.os.linux.help unless you are actively
  involved in the development of part of the networking	for Linux.  We
  ask that you please respect this general guideline for content.

  Recently, a similar group of mailing lists has started on the	host
  vger.rutgers.edu, using the much more	common majordomo mailing list
  server. Send mail to majordomo@vger.rutgers.edu to get help with what
  lists	are available, and how to join them.

  Also,	the news groups	comp.sys.ibm.pc.hardware.networking and
  comp.dcom.lans.ethernet should be used for questions that are	not
  Linux	specific.


  1.4.	Related	Documentation


  Much of this info came from saved postings from the comp.os.linux
  groups, which	shows that it is a valuable resource of	information.
  Other	useful information came	from a bunch of	small files by Donald
  himself. Of course, if you are setting up an Ethernet	card, then you
  will want to read the	NET-2 Howto so that you	can actually configure
  the software you will	use.  And last but not least, the contributions
  from the individuals and companies listed in ``Contributors''	is
  greatly appreciated as well. Oh yeah,	if you fancy yourself as a bit
  of a hacker, you can always scrounge some additional info from the
  driver source	files as well. There is	usually	a paragraph in there
  describing any important points.

  For those looking for	information that is not	specific in any	way to
  Linux	(i.e. what is 10BaseT, what is AUI, what does a	hub do,	etc.)  I
  strongly recommend the Ethernet-FAQ from the newsgroup
  comp.dcom.lans.ethernet. Look	on the FTP site	dorm.rutgers.edu in the
  directory /pub/novell/info_and_docs/ or grab it from the following
  URL:

  Ethernet FAQ
  (ftp://dorm.rutgers.edu/pub/novell/info_and_docs/Ethernet.FAQ)

  Don't	let the	fact that it was last revised in 1993 scare you, as not
  much has happened to Ethernet	since then. (Discounting the upcoming
  100Base-whatever, of course.)


  1.5.	New Versions of	this Document


  New versions of this document	can be retrieved via anonymous FTP from
  sunsite.unc.edu, in /pub/Linux/docs/HOWTO/* and various Linux	ftp
  mirror sites.	Updates	will be	made as	new information	/ drivers
  becomes available. If	this copy that you are reading is more than 2
  months old, it is either out of date,	or it means that I have	been
  lazy and haven't updated it.	This document was produced by using the
  SGML system that was specifically set	up for the Linux Howto project,
  and there are	various	output formats available, including, postscript,
  dvi, ascii, html, and	soon TeXinfo.

  I would recommend viewing it in the html (via	Mosaic)	or the
  Postscript/dvi format. Both of these contain cross-references	that are
  lost in the ascii translation.

  If you want to get the official copy off sunsite, here is URL.

  Ethernet-HOWTO (http://sunsite.unc.edu/mdw/HOWTO/Ethernet-HOWTO.html)

  If minor additions and changes have been made, you can view the latest
  working copy from this URL.

  Working Copy (http://rsphy1.anu.edu.au/~gpg109/Ethernet-HOWTO.html)




  2.  What card	should I buy for Linux?


  For impatient	users that just	want a quick, cheap answer the summary
  is: get 16 bit thinnet 8013 cards. For those who want	the absolute
  best performance, get	an AMD PC-Net/Lance based card.	For more detail
  as to	the who	what where and why, read on.


  2.1.	Eight bit vs 16	bit


  Unless you are a light user, or are confined to using	the smaller ISA
  slot,	the use	of the 8 bit cards like	the wd8003, the	3c503 and the
  ne1000 is usually not	worth the cost savings.	Get the	8013 or	the
  3c503/16, or the ne2000 instead. (The	3c501 is not included in this
  discussion, as it shouldn't be used under any	circumstances.)

  However, so not to leave you with a bad taste	in your	mouth if you
  happen to already have one, you can still expect to get about	500kB/s
  ftp download speed to	an 8 bit wd8003	card (on a 16MHz ISA bus) from a
  fast host.  And if most of your net-traffic is going to remote sites,
  then the bottleneck in the path will be elsewhere, and the only speed
  difference you will notice is	during net activity on your local
  subnet.

  A note to NFS	users: Some people have	found that using 8 bit cards in
  NFS clients causes poorer than expected performance, when using 8kB
  (native Sun) NFS packet size.

  The possible reason for this could be	due to the difference in on
  board	buffer size between the	8 bit and the 16 bit cards.  The 8 bit
  cards	have an	8kB buffer, and	the 16 bit cards have a	16kB buffer. The
  Linux	driver will reserve 3kB	of that	buffer (for Tx ping-pong
  buffers), leaving only 5kB for an 8 bit card.	The maximum ethernet
  packet size is about 1500 bytes. Now that 8kB	NFS packet will	arrive
  as about 6 back to back maximum size ethernet	packets. Both the 8 and
  16 bit cards have no problem Rx'ing back to back packets. The	problem
  arises when the machine doesn't remove the packets from the cards
  buffer in time, and the buffer overflows. The	fact that 8 bit	cards
  take an extra	ISA bus	cycle per transfer doesn't help	either.	What you
  can do if you	have an	8 bit card is either set the NFS transfer size
  to 4kB, or try increasing the	ISA bus	speed in order to get the card's
  buffer cleared out faster.


  2.2.	Low price Ethernet cards


  The lowest price seen	so far was in the March	'94 edition of LAN
  magazine. There was an ad for	Addtron	AE-200 cards (jumper settable
  NE2000 clones) for a measly $19 ea!  Unfortunately this offer	has
  since	expired. However, you might want to check to see what their
  everyday price is.

  You can also call AT-LAN-TEC at 301-948-7070.	Ask for	their technical
  support person. As with all purchases, you should indicate you are
  buying this for a Linux system.  NB: Their current NE2000 clone is a
  model	that `traps' other drivers that	probe into their address space.
  AT-LAN-TEC also carries a clone, non-EEPROM 8013 board for somewhat
  more,	and a NE2100 clone.  Either is a better	choice if the very
  lowest price isn't essential.

  And a	recent addition	is the VLB and PCI cards offered by Boca
  Research. These are selling for around the $70 mark, and these are
  supported with the latest kernel. These use the new 32 bit versions of
  the LANCE chip from AMD. See ``Boca Research'' for more info.

  If you require an ISA	card, you can use the the Allied Telesis AT1500
  which	uses the ISA version of	the LANCE chip from AMD.  It is	offered
  at a good price by many vendors.  Even Inmac,	known for their	premium
  markup, has this card	for under $100.	See ``AT-1500''	for more info.



  2.3.	Vendors	and Brands to Avoid


  These	vendors	have decided not to release programming	information
  about	their products,	without	signing	a NDA (non-disclosure
  agreement).  Hence it	is strongly advised that you avoid buying
  products offered from	these companies.

  (1) Cabletron	(see ``Cabletron'')

  (2) Xircom (see ``Xircom'')

  These	particular cards should	be avoided, as they are	obsolete.  The
  reasons as to	why they have been classified as such can be found in
  their	respective sections. For your particular application, these
  reasons may not be a concern,	so you should have a read of the reasons
  listed.

  (1) 3c501 (see ``3Com	3c501'')

  (2) Arcnet based cards (see ``Arcnet'')

  (3) Any 8-bit	cards (see ``Eight bit...'')


  2.4.	Type of	cable that your	card should support


  Unless you have to conform to	an existing network, you will want to
  use thinnet or thin ethernet cable. This is the style	with the
  standard BNC connectors. See ``Cables, Coax...''  for	other concerns
  with different types of ethernet cable.

  Most ethercards also come in a `Combo' version for only $10-$20 more.
  These	have both twisted pair and thinnet transceiver built-in,
  allowing you to change your mind later.

  The twisted pair cables, with	the RJ-45 (giant phone jack) connectors
  is technically called	10BaseT. You may also hear it called UTP
  (Unsheilded Twisted Pair).

  The thinnet, or thin ethernet	cabling, (RG-58	coaxial	cable) with the
  BNC (metal push and turn-to-lock) connectors is technically called
  10Base2.

  The older thick ethernet (10mm coaxial cable)	which is only found in
  older	installations is called	10Base5.

  Large	corporate installations	will most likely use 10BaseT instead of
  10Base2. 10Base2 does	not offer an easy upgrade path to the new
  upcoming 100Base-whatever.


  3.  Vendor/Manufacturer/Model	Specific Information



  The only thing that one needs	to use an ethernet card	with Linux is
  the appropriate driver. For this, it is essential that the
  manufacturer will release the	technical programming information to the
  general public without you (or anyone) having	to sign	your life away.
  A good guide for the likelihood of getting documentation (or,	if you
  aren't writing code, the likelihood that someone else	will write that
  driver you really, really need) is the availability of the Crynwr (nee
  Clarkson) packet driver. Russ	Nelson runs this operation, and	has been
  very helpful in supporting the development of	drivers	for Linux. Net-
  surfers can try this URL to look up Russ' software.

  Russ Nelson's	Packet Drivers (http://www.crynwr.com/crynwr/home.html)

  Given	the documentation, you can write a driver for your card	and use
  it for Linux (at least in theory) and	if you intend to write a driver,
  have a look at ``Skeleton driver'' as	well.  Keep in mind that some
  old hardware that was	designed for XT	type machines will not function
  very well in a multitasking environment such as Linux. Use of	these
  will lead to major problems if your network sees a reasonable	amount
  of traffic.

  Most cards come with drivers for MS-DOS interfaces such as NDIS and
  ODI, but these are useless for Linux.	Many people have suggested
  directly linking them	in or automatic	translation, but this is nearly
  impossible. The MS-DOS drivers expect	to be in 16 bit	mode and hook
  into `software interrupts', both incompatible	with the Linux kernel.
  This incompatibility is actually a feature, as some Linux drivers are
  considerably better than their MS-DOS	counterparts. The `8390' series
  drivers, for instance, use ping-pong transmit	buffers, which are only
  now being introduced in the MS-DOS world.

  Keep in mind that PC ethercards have the widest variety of interfaces
  (shared memory, programmed I/O, bus-master, or slave DMA) of any
  computer hardware for	anything, and supporting a new ethercard
  sometimes requires re-thinking most of the lower-level networking
  code.	(If you	are interested in learning more	about these different
  forms	of interfaces, see ``Programmed	I/O vs.	...''.)

  Also,	similar	product	numbers	don't always indicate similar products.
  For instance,	the 3c50* product line from 3Com varies	wildly between
  different members.

  Enough talk. Let's get down to the information you want.


  3.1.	3Com


  If you are not sure what your	card is, but you think it is a 3Com
  card,	you can	probably figure	it out from the	assembly number. 3Com
  has a	document `Identifying 3Com Adapters By Assembly	Number'	(ref
  24500002) that would most likely clear things	up. See	``Technical
  Information from 3Com'' for info on how to get documents from	3Com.

  Also note that 3Com has a FTP	site with various goodies: ftp.3Com.com
  that you may want to check out.


  3.1.1.  3c501


  Status -- Semi-Supported

  Too brain-damaged to use. Available surplus from many	places.	Avoid it
  like the plague. Again, do not purchase this card, even as a joke.
  It's performance is horrible,	and it breaks in many ways.
  Cameron L. Spitzer of	3Com said: ``I'm speaking only for myself here,
  of course, but I believe 3Com	advises	against	installing a 3C501 in a
  new system, mostly for the same reasons Donald has discussed.	You
  probably won't be happy with the 3C501 in your Linux box. The	data
  sheet	is marked `(obsolete)' on 3Com's Developers' Order Form, and the
  board	is not part of 3Com's program for sending free Technical
  Reference Manuals to people who need them. The decade-old things are
  nearly indestructible, but that's about all they've got going	for them
  any more.''

  For those not	yet convinced, the 3c501 can only do one thing at a time
  -- while you are removing one	packet from the	single-packet buffer it
  cannot receive another packet, nor can it receive a packet while
  loading a transmit packet. This was fine for a network between two
  8088-based computers where processing	each packet and	replying took
  10's of msecs, but modern networks send back-to-back packets for
  almost every transaction.

  Donald writes: `The driver is	now in the std.	kernel,	but under the
  following conditions:	This is	unsupported code. I know the usual
  copyright says all the code is unsupported, but this is _really_
  unsupported. I DON'T want to see bug reports,	and I'll accept	bug
  fixes	only if	I'm in a good mood that	day.

  I don't want to be flamed later for putting out bad software.	I don't
  know all all of the 3c501 bugs, and I	know this driver only handles a
  few that I've	been able to figure out. It has	taken a	long intense
  effort just to get the driver	working	this well.'

  AutoIRQ works, DMA isn't used, the autoprobe only looks at 0x280 and
  0x300, and the debug level is	set with the third boot-time argument.

  Once again, the use of a 3c501 is strongly discouraged!  Even	more so
  with a IP multicast kernel, as you will grind	to a halt while
  listening to all multicast packets. See the comments at the top of the
  source code for more details.


  3.1.2.  3c503, 3c503/16


  Status -- Supported

  3Com shared-memory ethercards. They also have	a programmed I/O mode
  that doesn't use the 8390 facilities (their engineers	found too many
  bugs!)  It should be about the same speed as the same	bus width
  WD80x3, Unless you are a light user, spend the extra money and get the
  16 bit model,	as the price difference	isn't significant. The 3c503
  does not have	``EEPROM setup'', so the diagnostic/setup program isn't
  needed before	running	the card with Linux. The shared	memory address
  of the 3c503 is set using jumpers that are shared with the boot PROM
  address. This	is confusing to	people familiar	with other ISA cards,
  where	you always leave the jumper set	to ``disable'' unless you have a
  boot PROM.

  The Linux 3c503 driver can also work with the	3c503 programmed-I/O
  mode,	but this is slower and less reliable than shared memory	mode.
  Also,	programmed-I/O mode is not tested when updating	the drivers, the
  deadman (deadcard?) check code may falsely timeout on	some machines,
  and the probe	for a 3c503 in programmed-I/O mode is turned off by
  default in some versions of the kernel. This was a panic reaction to
  the general device driver probe explosion; the 3c503 shared memory
  probe	is a safe read from memory, rather than	an extensive scan
  through I/O space. As	of 0.99pl13, the kernel	has an I/O port
  registrar that makes I/O space probes	safer, and the programmed-I/O
  3c503	probe has been re-enabled.  You	still shouldn't	use the
  programmed-I/O mode though, unless you need it for MS-DOS
  compatibility.

  The 3c503's IRQ line is set in software, with	no hints from an EEPROM.
  Unlike the MS-DOS drivers, the Linux driver has capability to	autoIRQ:
  it uses the first available IRQ line in {5,2/9,3,4}, selected	each
  time the card	is ifconfig'ed.	(Older driver versions selected	the IRQ
  at boot time.) The ioctl() call in `ifconfig'	will return EAGAIN if no
  IRQ line is available	at that	time.

  Some common problems that people have	with the 503 are discussed in
  ``Problems with...''.



  3.1.3.  3c505


  Status -- Semi-Supported

  This is a driver that	was written by Craig Southeren
  geoffw@extro.ucc.su.oz.au. These cards also use the i82586 chip.  I
  don't	think there are	that many of these cards about.	 It is included
  in the standard kernel, but it is classed as an alpha	driver.	See
  ``Alpha Drivers'' for	important information on using alpha-test
  ethernet drivers with	Linux.

  There	is also	the file /usr/src/linux/drivers/net/README.3c505 that
  you should read if you are going to use one of these cards.  It
  contains various options that	you can	enable/disable.	 Technical
  information is available in ``Programming the	Intel chips''.


  3.1.4.  3c507

  Status -- Semi-Supported

  This card uses one of	the Intel chips, and the development of	the
  driver is closely related to the development of the Intel Ether
  Express driver.  The driver is included in the standard kernel
  release, but as an alpha driver.

  See ``Alpha Drivers''	for important information on using alpha-test
  ethernet drivers with	Linux. Technical information is	available in
  ``Programming	the Intel chips''.


  3.1.5.  3c509	/ 3c509B


  Status -- Supported

  It's fairly inexpensive and has excellent performance	for a non-bus-
  master design.  The drawbacks	are that the original 3c509 _requires_
  very low interrupt latency. The 3c509B shouldn't suffer from the same
  problem, due to having a larger buffer. (See below.)

  Note that the	ISA card detection uses	a different method than	most
  cards. Basically, you	ask the	cards to respond by sending data to an
  ID_PORT (port	0x100).	Note that if you have some other strange ISA
  card using an	I/O range that includes	the ID_PORT of the 3c509, it
  will probably	not get	detected. Note that you	can change the ID_PORT
  to 0x110 or 0x120 or... in 3c509.c if	you have a conflicting ISA card,
  and the 3c509	will still be happy.  Also note	that this detection
  method means that it is difficult to predict which card will get
  detected first in a multiple ISA 3c509 configuration.	 The card with
  the lowest hardware ethernet address will end	up being eth0. This
  shouldn't matter to anyone, except for those people who want to assign
  a 6 byte hardware address to a particular interface.

  A working 3c509 driver was first included as an alpha-test version in
  the 0.99pl13 kernel sources.	It is now in the standard kernel.

  The original 3c509 has a tiny	Rx buffer (2kB), causing the driver to
  occasionally drop a packet if	interrupts are masked for too long. To
  minimize this	problem, you can try unmasking interrupts during IDE
  disk transfers (see hdparm(8)) and/or	increasing your	ISA bus	speed so
  IDE transfers	finish sooner.	(Note that the driver could be
  completely rewritten to use predictive interrupts, but performance re-
  writes of working drivers are	low priority unless there is some
  particular incentive or need.)

  The newer model 3c509B has 8kB on board, and the driver can set 4, 5
  or 6kB for an	Rx buffer. This	setting	can also be stored on the
  EEPROM. This should alleviate	the above problem with the original
  3c509. At this point in time,	the Linux driver is not	aware of this,
  and treats the 3c509B	as an older 3c509.

  Apparently, 3c509B users may have to use the supplied	DOS utility to
  disable the plug and play support, and to set	the output media to what
  they require.

  Cameron Spitzer writes: ``Beware that	if you put a '509 in EISA
  addressing mode by mistake and save that in the EEPROM, you'll have to
  use an EISA machine or the infamous Test Via to get it back to normal,
  and it will conflict at IO location 0	which may hang your ISA	machine.
  I believe this problem is corrected in the 3C509B version of the
  board.''


  3.1.6.  3c523


  Status -- Not	Supported

  This MCA bus card uses the i82586, and now that people are actually
  running Linux	on MCA machines, someone may wish to try and recycle
  parts	of the 3c507 driver into a driver for this card.


  3.1.7.  3c527


  Status -- Not	Supported

  Yes, another MCA card. No, not too much interest in it.  Better
  chances with the 3c523 or the	3c529.


  3.1.8.  3c529


  Status -- Not	Supported

  This card actually uses the same chipset as the 3c509.  Donald
  actually put hooks into the 3c509 driver to check for	MCA cards after
  probing for EISA cards, and before probing for ISA cards. But	it
  hasn't evolved much further than that. Donald	writes:

  ``I don't have access	to a MCA machine (nor do I fully understand the
  probing code)	so I never wrote the mca_adaptor_select_mode() or
  mca_adaptor_id() routines. If	you can	find a way to get the adaptor
  I/O address that assigned at boot time, you can just hard-wire that in
  place	of the commented-out probe. Be sure to keep the	code that reads
  the IRQ, if_port, and	ethernet address.''

  3.1.9.  3c579


  Status -- Supported

  The EISA version of the 509. The current EISA	version	uses the same 16
  bit wide chip	rather than a 32 bit interface,	so the performance
  increase isn't stunning.  The	EISA probe code	was added to 3c509.c for
  0.99pl14.  We	would be interested in hearing progress	reports	from any
  3c579	users. (Read the above 3c509 section for info on the driver.)

  Cameron Spitzer writes: ``The	3C579 (Etherlink III EISA) should be
  configured as	an EISA	card. The IO Base Address (window 0 register 6
  bits 4:0) should be 1f, which	selects	EISA addressing	mode. Logic
  outside the ASIC decodes the IO address s000,	where s	is the slot
  number. I don't think	it was documented real well. Except for	its IO
  Base Address,	the '579 should	behave EXACTLY like the'509 (EL3 ISA),
  and if it doesn't, I want to hear about it (at my work address).''



  3.1.10.  3c589 / 3c589B


  Status -- Semi-Supported

  Many people have been	using this PCMCIA card for quite some time now.
  Note that support for	it is not (at present) included	in the default
  kernel source	tree. Note that	you will need a	supported PCMCIA
  controller chipset. There are	drivers	available on Donald's ftp site:


       cesdis.gsfc.nasa.gov:/pub/linux/pcmcia/README.3c589 ces-
       dis.gsfc.nasa.gov:/pub/linux/pcmcia/3c589.c ces-
       dis.gsfc.nasa.gov:/pub/linux/pcmcia/dbether.c


  Or for those that are	net-surfing you	can try:

  Don's	PCMCIA Stuff (http://cesdis.gsfc.nasa.gov/linux/pcmcia.html)

  You will still need a	PCMCIA socket enabler as well.

  See ``PCMCIA Support'' for more info on PCMCIA chipsets, socket
  enablers, etc.

  The "B" in the name means the	same here as it	does for the 3c509 case.


  3.2.	Accton



  3.2.1.  Accton MPX


  Status -- Supported

  Don't	let the	name fool you. This is still supposed to be a NE2000
  compatible card. The MPX is supposed to stand	for MultiPacket
  Accelerator, which, according	to Accton, increases throughput
  substantially. But if	you are	already	sending	back-to-back packets,
  how can you get any faster...


  3.2.2.  Accton EN2212	PCMCIA Card


  Status -- Semi-Supported

  David	Hinds has been working on a driver for this card, and you are
  best to check	the latest release of his PCMCIA package to see	what the
  present status is.


  3.3.	Allied Telesis



  3.3.1.  AT1500


  Status --Supported

  These	are a series of	low-cost ethercards using the 79C960 version of
  the AMD LANCE. These are bus-master cards, and thus probably the
  fastest ISA bus ethercards available (although the 3c509 has lower
  latency thanks to predictive interrupts).

  DMA selection	and chip numbering information can be found in ``AMD
  LANCE''.

  More technical information on	AMD LANCE based	Ethernet cards can be
  found	in ``Notes on AMD...''.


  3.3.2.  AT1700


  Status -- Supported

  The Allied Telesis AT1700 series ethercards are based	on the Fujitsu
  MB86965. This	chip uses a programmed I/O interface, and a pair of
  fixed-size transmit buffers. This allows small groups	of packets to
  sent be sent back-to-back, with a short pause	while switching	buffers.

  A unique feature is the ability to drive 150ohm STP (Shielded	Twisted
  Pair)	cable commonly installed for Token Ring, in addition to	10baseT
  100ohm UTP (unshielded twisted pair).

  The Fujitsu chip used	on the AT1700 has a design flaw: it can	only be
  fully	reset by doing a power cycle of	the machine.  Pressing the reset
  button doesn't reset the bus interface. This wouldn't	be so bad,
  except that it can only be reliably detected when it has been	freshly
  reset. The solution/work-around is to	power-cycle the	machine	if the
  kernel has a problem detecting the AT1700.

  Some production runs of the AT1700 had another problem: they are
  permanently wired to DMA channel 5.  This is undocumented, there are
  no jumpers to	disable	the "feature", and no driver dares use the DMA
  capability because of	compatibility problems.	No device driver will be
  written using	DMA if installing a second card	into the machine breaks
  both,	and the	only way to disable the	DMA is with a knife.

  The at1700 driver is included	in the standard	kernel source tree.



  3.4.	AMD / Advanced Micro Devices



  3.4.1.  AMD LANCE (7990, 79C960, PCnet-ISA)


  Status -- Supported

  There	really is no AMD ethernet card.	You are	probably reading this
  because the only markings you	could find on your card	said AMD and the
  above	number.	The 7990 is the	original `LANCE' chip, but most	stuff
  (including this document) refer to all these similar chips as	`LANCE'
  chips. (...incorrectly, I might add.)

  These	above numbers refer to chips from AMD that are the heart of many
  ethernet cards.  For example,	the Allied Telesis AT1500 (see
  ``AT1500'') the NE1500/2100 (see ``NE1500'') and the Boca-VLB/PCI
  cards	(see ``Boca-VLB/PCI'')

  The 79C960 (a.k.a. PCnet-ISA)	contains enhancements and bug fixes over
  the original 7990 LANCE design.

  Chances are that the existing	LANCE driver will work with all	AMD
  LANCE	based cards. (except perhaps the NI65XX	- see ``NI65XX'' for
  more info on that one.)  This	driver should also work	with NE1500 and
  NE2100 clones.

  For the ISA bus master mode all structures used directly by the LANCE,
  the initialization block, Rx and Tx rings, and data buffers, must be
  accessible from the ISA bus, i.e. in the lower 16M of	real memory.  If
  more than 16MB of memory is installed, low-memory `bounce-buffers' are
  used when needed.

  The DMA channel can be set with the low bits of the otherwise-unused
  dev->mem_start value (a.k.a. PARAM_1).  (see ``PARAM_1'') If unset it
  is probed for	by enabling each free DMA channel in turn and checking
  if initialization succeeds.

  The HP-J2405A	board is an exception: with this board it's easy to read
  the EEPROM-set values	for the	IRQ, and DMA.

  See ``Notes on AMD...''  for more info on these chips.


  3.4.2.  AMD 79C961 (PCnet-ISA+)


  Status -- Supported

  This is the PCnet-ISA+  -- an	enhanced version of the	79C960.	 It has
  support for jumper-less configuration	and Plug and Play.  See	the info
  in the above section.


  3.4.3.  AMD 79C965 (PCnet-32)


  Status -- Supported

  This is the PCnet-32 -- a 32 bit bus-master version of the original
  LANCE	chip for VL-bus	and local bus systems.	Minor cleanups were
  added	to the original	lance driver around v1.1.50 to support these 32
  bit versions of the LANCE chip.  The main problem was	that the current
  versions of the '965 and '970	chips have a minor bug.	 They clear the
  Rx buffer length field in the	Rx ring	when they are explicitly
  documented not to. Again, see	the above info.


  3.4.4.  AMD 79C970 (PCnet-PCI)


  Status -- Supported

  This is the PCnet-PCI	-- similar to the PCnet-32, but	designed for PCI
  bus based systems. Again, see	the above info.	 Donald	has modified the
  LANCE	driver to use the PCI BIOS structure that was introduced by Drew
  Eckhardt for the PCI-NCR SCSI	driver.	This means that	you need to
  build	a kernel with PCI BIOS support enabled.


  3.4.5.  AMD 79C974 (PCnet-SCSI)


  Status -- Supported

  This is the PCnet-SCSI --  which is basically	treated	like a '970 from
  an Ethernet point of view. A minor '974 specific fix was added to the
  1.1.8x kernels, so get a 1.1.90 or newer kernel. Also	see the	above
  info.	Don't ask if the SCSI half of the chip is supported -- this is
  the Ethernet-Howto, not the SCSI-Howto.


  3.5.	Ansel Communications



  3.5.1.  AC3200 EISA


  Status -- Semi-Supported

  This driver is included in the present kernel	as an alpha test driver.
  Please see ``Alpha Drivers'' in this document	for important
  information regarding	alpha drivers.	If you use it, let Donald know
  how things work out, as not too many people have this	card and
  feedback has been low.


  3.6.	Apricot



  3.6.1.  Apricot Xen-II On Board Ethernet


  Status -- Supported

  This on board	ethernet uses an i82596	bus-master chip.  It can only be
  at i/o address 0x300.	The author of this driver is Mark Evans. By
  looking at the driver	source,	it appears that	the IRQ	is hardwired to
  10.

  Earlier versions of the driver had a tendency	to think that anything
  living at 0x300 was an apricot NIC.  Since then the hardware address
  is checked to	avoid these false detections.


  3.7.	Arcnet



  Status -- Semi-Supported

  With the very	low cost and better performance	of ethernet, chances are
  that most places will	be giving away their Arcnet hardware for free,
  resulting in a lot of	home systems with Arcnet.

  An advantage of Arcnet is that all of	the cards have identical
  interfaces, so one driver will work for everyone.

  Recent interest in getting Arcnet going has picked up	again and Avery
  Pennarun's alpha driver has been put into the	default	kernel sources
  for 1.1.80 and above.	The arcnet driver uses `arc0' as its name
  instead of the usual `eth0' for ethernet devices.  Bug reports and
  success stories can be mailed	to:

  apenwarr@tourism.807-city.on.ca


  3.8.	AT&T


  Note that AT&T's StarLAN is an orphaned technology, like SynOptics
  LattisNet, and can't be used in a standard 10Base-T environment.


  3.8.1.  AT&T T7231 (LanPACER+)


  Status -- Not	Supported

  These	StarLAN	cards use an interface similar to the i82586 chip. At
  one point, Matthijs Melchior (matthijs.n.melchior@att.com) was playing
  with the 3c507 driver, and almost had	something useable working.
  Haven't heard	much since that.


  3.9.	AT-Lan-Tec / RealTek



  3.9.1.  AT-Lan-Tec / RealTek Pocket adaptor


  Status -- Supported

  This is a generic, low-cost OEM pocket adaptor being sold by AT-Lan-
  Tec, and (likely) a number of	other suppliers. A driver for it is
  included in the standard kernel.  Note that there is substantial
  information contained	in the driver source file `atp.c'.  BTW, the
  adaptor (AEP-100L) has both 10baseT and BNC connections!  You	can
  reach	AT-Lan-Tec at 1-301-948-7070. Ask for the model	that works with
  Linux, or ask	for tech support.

  In the Netherlands a compatible adaptor is sold under	the name SHI-TEC
  PE-NET/CT, and sells for about $125. The vendor was Megasellers.  They
  state	that they do not sell to private persons, but this doesn't
  appear to be strictly	adhered	to.  They are: Megasellers, Vianen, The
  Netherlands. They always advertise in	Dutch computer magazines.  Note
  that the newer model EPP-NET/CT appears to be	significantly different
  than the PE-NET/CT, and will not work	with the present driver.
  Hopefully someone will come up with the programming information and
  this will be fixed up.

  In Germany, a	similar	adaptor	comes as a no-brand-name product. Prolan
  890b,	no brand on the	casing,	only a roman II. Resellers can get a
  price	of about $130, including a small wall transformer for the power.
  The adaptor is `normal size' for the product class, about 57mm wide,
  22mm high tapering to	15mm high at the DB25 connector, and 105mm long
  (120mm including the BNC socket). It's switchable between the	RJ45 and
  BNC jacks with a small slide switch positioned between the two: a very
  intuitive design.

  Donald performed some	power draw measurements, and determined	that the
  average current draw was only	about 100mA @ 5V.  This	power draw is
  low enough that you could buy	or build a cable to take the 5V	directly
  from the keyboard/mouse port available on many laptops. (Bonus points
  here for using a standardized	power connector	instead	of a proprietary
  one.)

  Note that the	device name that you pass to ifconfig is not eth0 but
  atp0 for this	device.



  3.10.	 Boca Research


  Yes, they make more than just	multi-port serial cards.  :-)


  3.10.1.  Boca	BEN (PCI, VLB)


  Status -- Supported

  These	cards are based	on AMD's PCnet chips, used in the AT1500 and the
  like.	You can	pick up	a combo	(10BaseT and 10Base2) PCI card for under
  $70 at the moment.

  Supposedly Boca PCI cards can	have trouble with Pentium systems that
  are operating	faster than 66MHz. You may want	to check with Boca on
  this one. Note that this is not a driver problem, as it hits
  DOS/Win/NT users as well. Any	additional info	on this	as it develops
  would	be appreciated.

  More information can be found	in ``AMD LANCE''.

  More technical information on	AMD LANCE based	Ethernet cards can be
  found	in ``Notes on AMD...''.


  3.11.	 Cabletron


  Donald writes: `Yes, another one of these companies that won't release
  its programming information. They waited for months before actually
  confirming that all their information	was proprietary, deliberately
  wasting my time. Avoid their cards like the plague if	you can.  Also
  note that some people	have phoned Cabletron, and have	been told things
  like `a D. Becker is working on a driver for linux' -- making	it sound
  like I work for them.	This is	NOT the	case.'

  If you feel like asking them why they	don't want to release their low
  level	programming info so that people	can use	their cards, write to
  support@ctron.com.  Tell them	that you are using Linux, and are
  disappointed that they don't support open systems. And no, the usual
  driver development kit they supply is	useless. It is just a DOS object
  file that you	are supposed to	link against. Which you	aren't allowed
  to even reverse engineer.



  3.11.1.  E10**, E10**-x, E20**, E20**-x


  Status -- Semi-Supported

  These	are NEx000 almost-clones that are reported to work with	the
  standard NEx000 drivers, thanks to a ctron-specific check during the
  probe. If there are any problems, they are unlikely to be fixed, as
  the programming information is unavailable.


  3.11.2.  E2100


  Status -- Semi-Supported

  Again, there is not much one can do when the programming information
  is proprietary.  The E2100 is	a poor design. Whenever	it maps	its
  shared memory	in during a packet transfer, it	maps it	into the whole
  128K region! That means you can't safely use another interrupt-driven
  shared memory	device in that region, including another E2100.	 It will
  work most of the time, but every once	in a while it will bite	you.
  (Yes,	this problem can be avoided by turning off interrupts while
  transferring packets,	but that will almost certainly lose clock
  ticks.) Also,	if you mis-program the board, or halt the machine at
  just the wrong moment, even the reset	button won't bring it back. You
  will have to turn it off and leave it	off for	about 30 seconds.

  Media	selection is automatic,	but you	can override this with the low
  bits of the dev->mem_end parameter.  See ``PARAM_2''

  Also,	don't confuse the E2100	for a NE2100 clone.  The E2100 is a
  shared memory	NatSemi	DP8390 design, roughly similar to a brain-
  damaged WD8013, whereas the NE2100 (and NE1500) use a	bus-mastering
  AMD LANCE design.

  There	is an E2100 driver included in the standard kernel.  However,
  seeing as programming	info isn't available, don't expect bug-fixes.
  Don't	use one	unless you are already stuck with the card.



  3.12.	 D-Link


  Some people have had difficulty in finding vendors that carry	D-link
  stuff. This should help.


		  (714)	455-1688  in the US
		  (081)	203-9900  in the UK
		  6196-643011	  in Germany
		  (416)	828-0260  in Canada
		  (02) 916-1600	  in Taiwan




  3.12.1.  DE-100, DE-200, DE-220-T


  Status -- Supported

  The manual says that it is 100 % compatible with the NE2000. This is
  not true. You	should call them and tell them you are using their card
  with Linux, and they should correct their documentation. Some
  pre-0.99pl12 driver versions may have	trouble	recognizing the	DE2**
  series as 16 bit cards, and these cards are the most widely reported
  as having the	spurious transfer address mismatch errors. Note	that
  there	are cards from Digital (DEC) that are also named DE100 and
  DE200, but the similarity stops there.


  3.12.2.  DE-530


  Status -- Semi-Supported

  This appears to be a generic DEC 21040 PCI chip implementation, and
  will most likely work	with the generic 21040 driver.	However, nobody
  has verified this yet, and until that	has happened, it will remain
  listed as Semi-Supported.

  See ``DEC 21040'' for	more information on these cards, and the present
  driver situation.


  3.12.3.  DE-600


  Status -- Supported

  Laptop users and other folk who might	want a quick way to put	their
  computer onto	the ethernet may want to use this. The driver is
  included with	the default kernel source tree.	 Bjorn Ekwall
  bj0rn@blox.se	wrote the driver.  Expect about	80kb/s transfer	speed
  from this via	the parallel port. You should read the README.DLINK file
  in the kernel	source tree.

  Note that the	device name that you pass to ifconfig is now eth0 and
  not the previously used dl0.

  If your parallel port	is not at the standard 0x378 then you will have
  to recompile.	Bjorn writes: ``Since the DE-620 driver	tries to sqeeze
  the last microsecond from the	loops, I made the irq and port address
  constants instead of variables. This makes for a usable speed, but it
  also means that you can't change these assignements from e.g.	lilo;
  you _have_ to	recompile...'' Also note that some laptops implement the
  on-board parallel port at 0x3bc which	is where the parallel ports on
  monochrome cards were/are.

  Supposedly, a	no-name	ethernet pocket	adaptor	marketed under the name
  `PE-1200' is DE-600 compatible.  It is available in Europe from:


	  SEMCON Handels Ges.m.b.h
	  Favoritenstrasse 20
	  A-1040 WIEN
	  Telephone: (+43) 222 50 41 708
	  Fax	   : (+43) 222 50 41 706




  3.12.4.  DE-620


  Status -- Supported

  Same as the DE-600, only with	two output formats.  Bjorn has written a
  driver for this model, for kernel versions 1.1 and above. See	the
  above	information on the DE-600.
  3.12.5.  DE-650


  Status -- Semi-Supported

  Some people have been	using this PCMCIA card for some	time now with
  their	notebooks. It is a basic 8390 design, much like	a NE2000. The
  LinkSys PCMCIA card and the IC-Card Ethernet (available from Midwest
  Micro) are supposedly	DE-650 clones as well.	Note that at present,
  this driver is not part of the standard kernel, and so you will have
  to do	some patching.

  See ``PCMCIA Support'' in this document, and if you can, have	a look
  at:

  Don's	PCMCIA Stuff (http://cesdis.gsfc.nasa.gov/linux/pcmcia.html)


  3.13.	 DFI



  3.13.1.  DFINET-300 and DFINET-400


  Status -- Supported

  These	cards are now detected (as of 0.99pl15)	thanks to Eberhard
  Moenkeberg emoenke@gwdg.de who noted that they use `DFI' in the first
  3 bytes of the prom, instead of using	0x57 in	bytes 14 and 15, which
  is what all the NE1000 and NE2000 cards use. (The 300	is an 8	bit
  pseudo NE1000	clone, and the 400 is a	pseudo NE2000 clone.)



  3.14.	 Digital / DEC



  3.14.1.  DEPCA, DE100, DE200/1/2, DE210, DE422


  Status -- Supported

  As of	linux v1.0, there is a driver included as standard for these
  cards. It was	written	by David C. Davies.  There is documentation
  included in the source file `depca.c', which includes	info on	how to
  use more than	one of these cards in a	machine. Note that the DE422 is
  an EISA card.	These cards are	all based on the AMD LANCE chip.  See
  ``AMD	LANCE''	for more info.	A maximum of two of the	ISA cards can be
  used,	because	they can only be set for 0x300 and 0x200 base I/O
  address.  If you are intending to do this, please read the notes in
  the driver source file depca.c in the	standard kernel	source tree.


  3.14.2.  Digital EtherWorks 3	(DE203,	DE204, DE205)


  Status -- Supported

  Included into	kernels	v1.1.62	and above is this driver, also by David
  C. Davies of DEC. These cards	use a proprietary chip from DEC, as
  opposed to the LANCE chip used in the	earlier	cards like the DE200.
  These	cards support both shared memory or programmed I/O, although you
  take about a 50%performance hit if you use PIO mode. The shared memory
  size can be set to 2kB, 32kB or 64kB,	but only 2 and 32 have been
  tested with this driver. David says that the performance is virtually
  identical between the	2kB and	32kB mode. There is more information
  (including using the driver as a loadable module) at the top of the
  driver file ewrk3.c and also in README.ewrk3.	 Both of these files
  come with the	standard kernel	distribution.

  Other	interesting notes are that it appears that David is/was	working
  on this driver for the unreleased version of Linux for the DEC Alpha
  AXP. And the standard	driver has a number of interesting ioctl() calls
  that can be used to get or clear packet statistics, read/write the
  EEPROM, change the hardware address, and the like. Hackers can see the
  source code for more info on that one.

  David	has also written a configuration utility for this card (along
  the lines of the DOS program NICSETUP.EXE) along with	other tools.
  These	can be found on	sunsite.unc.edu	in the directory
  /pub/Linux/system/Network/management -- look for the file ewrk3tools-
  X.XX.tar.gz.


  3.14.3.  DE425 (EISA), DE434,	DE435


  Status -- Supported

  These	cards are based	on the 21040 chip mentioned below.  Included
  into kernels v1.1.86 and above is this driver, also by David C. Davies
  of DEC. It sure is nice to have support from someone on the inside
  ;-) Have a read of the 21040 section for extra info.

  Note that as of 1.1.91, David	has added a compile time option	that may
  allow	non-DEC	cards (such as the ZYNX	cards) to work with this driver.
  Have a look at README.de4x5 for details.


  3.14.4.  DEC 21040, 21140, Tulip


  Status -- Supported

  The DEC 21040	is a bus-mastering single chip ethernet	solution from
  Digital, similar to AMD's PCnet chip.	The 21040 is specifically
  designed for the PCI bus architecture.  SMC's	new EtherPower PCI card
  uses this chip.  The new 21140 recently announced is for supporting
  100Base-? and	is supposed to be able to work with drivers for	the
  21040	chip.

  You have a choice of two drivers for cards based on this chip. There
  is the DE425 driver discussed	above, and the generic 21040 driver that
  Donald has written.

  To use David's de4x5 driver with non-DEC cards, have a look at
  README.de4x5 for details.

  Donald is doing his generic 21040 driver development on a SMC
  EtherPower PCI card at the moment, and this driver is	included in the
  standard kernel source as of 1.1.84.	Note that this driver is still
  considered an	alpha driver (see ``Alpha Drivers'') at	the moment, and
  should be treated as such. To	use it,	you will have to edit
  arch/i386/config.in and uncomment the	line for CONFIG_DEC_ELCP
  support.





  3.15.	 Farallon

  Farallon sells EtherWave adaptors and	transceivers. This device allows
  multiple 10baseT devices to be daisy-chained.


  3.15.1.  Farallon Etherwave


  Status -- Supported

  This is reported to be a 3c509 clone that includes the EtherWave
  transceiver. People have used	these successfully with	Linux and the
  present 3c509	driver.	They are too expensive for general use,	but are
  a great option for special cases.  Hublet prices start at $125, and
  Etherwave adds $75-$100 to the price of the board -- worth it	if you
  have pulled one wire too few,	but not	if you are two network drops
  short.


  3.16.	 Hewlett Packard


  The 272** cards use programmed I/O, similar to the NE*000 boards, but
  the data transfer port can be	`turned	off' when you aren't accessing
  it, avoiding problems	with autoprobing drivers.

  Thanks to Glenn Talbott for helping clean up the confusion in	this
  section regarding the	version	numbers	of the HP hardware.


  3.16.1.  27245A


  Status -- Supported

  8 Bit	8390 based 10BaseT, not	recommended for	all the	8 bit reasons.
  It was re-designed a couple years ago	to be highly integrated	which
  caused some changes in initialization	timing which only affected
  testing programs, not	LAN drivers. (The new card is not `ready' as
  soon after switching into and	out of loopback	mode.)


  3.16.2.  HP PC Lan+ (27247A, 27247B, 27252A)


  Status -- Supported

  The HP PC Lan+ is different to the standard HP PC Lan	card. This
  driver was added to the list of drivers in the standard kernel at
  about	v1.1.3X. Note that even	though the driver is included, the entry
  in `config.in' seems to have been omitted. If	you want to use	it, and
  it doesn't come up in	`config.in' then add the following line	to
  `config.in' under the	 `HP PCLAN support' line:


	  bool 'HP PCLAN Plus support' CONFIG_HPLAN_PLUS n



  Then run make	config;make dep;make zlilo or whatever.

  The 47B is a 16 Bit 8390 based 10BaseT w/AUI,	and the	52A is a 16 Bit
  8390 based ThinLAN w/AUI.  These cards are high performers (3c509
  speed) without the interrupt latency problems	(32K onboard RAM for TX
  or RX	packet buffering). They	both offer LAN connector autosense, data
  I/O in I/O space (simpler) or	memory mapped (faster),	and soft
  configuration.

  The 47A is the older model that existed before the `B'.  Two versions
  27247-60001 or 27247-60002 have part numbers marked on the card.
  Functionally the same	to the LAN driver, except bits in ROM to
  identify boards differ. -60002 has a jumper to allow operation in non-
  standard ISA busses (chipsets	that expect IOCHRDY early.)



  3.16.3.  HP-J2405A


  Status -- Supported

  These	are lower priced, and slightly faster than the 27247B/27252A,
  but are missing some features, such as AUI, ThinLAN connectivity, and
  boot PROM socket.  This is a fairly generic LANCE design, but	a minor
  design decision makes	it incompatible	with a generic `NE2100'	driver.
  Special support for it (including reading the	DMA channel from the
  board) is included thanks to information provided by HP's Glenn
  Talbott.

  More technical information on	LANCE based cards can be found in
  ``Notes on AMD...''


  3.16.4.  HP-Vectra On	Board Ethernet


  Status -- Supported

  The HP-Vectra	has an AMD PCnet chip on the motherboard.  Earlier
  kernel versions would	detect it as the HP-J2405A but that would fail,
  as the Vectra	doesn't	report the IRQ and DMA channel like the	J2405A.
  Get a	kernel newer than v1.1.53 to avoid this	problem.

  DMA selection	and chip numbering information can be found in ``AMD
  LANCE''.

  More technical information on	LANCE based cards can be found in
  ``Notes on AMD...''


  3.17.	 IBM / International Business Machines



  3.17.1.  IBM Thinkpad	300


  Status -- Supported

  This is compatible with the Intel based Zenith Z-note.  See ``Z-note''
  for more info.

  Supposedly this site has a comprehensive database of useful stuff for
  newer	versions of the	Thinkpad. I haven't checked it out myself yet.

  Thinkpad-info	(http://peipa.essex.ac.uk/html/linux-thinkpad.html)

  For those without a WWW browser handy, try
  peipa.essex.ac.uk:/pub/tp750/


  3.17.2.  IBM Credit Card Adaptor for Ethernet


  Status -- Semi-Supported

  People have been using this PCMCIA card with Linux as	well.  Similar
  points apply,	those being that you need a supported PCMCIA chipset on
  your notebook, and that you will have	to patch the PCMCIA support into
  the standard kernel.

  See ``PCMCIA Support'' in this document, and if you can, have	a look
  at:

  Don's	PCMCIA Stuff (http://cesdis.gsfc.nasa.gov/linux/pcmcia.html)



  3.18.	 Intel Ethernet	Cards



  3.18.1.  Ether Express


  Status -- Semi-Supported

  This card uses the intel i82586. (Surprise, huh?)  The driver	is in
  the standard release of the kernel, as an alpha driver. See ``Alpha
  Drivers'' for	important information on using alpha-test ethernet
  drivers with Linux.

  The reason is	that the driver	works well with	slow machines, but the
  i82586 occasionally hangs from the packet buffer contention that a
  fast machine can cause.  One reported	hack/fix is to change all of the
  outw() calls to outw_p(). Also, the driver is	missing	promiscuous and
  multicast modes. (See	``Multicast and...'')

  There	is also	the standard way of using the chip (read slower) that is
  described in the chip	manual,	and used in other i82586 drivers, but
  this would require a re-write	of the entire driver.

  There	is some	technical information available	on the i82586 in
  ``Programming	the Intel Chips'' and also in the source code for the
  driver `eexpress.c'. Don't be	afraid to read it. ;-)


  3.18.2.  Ether Express PRO


  Status -- Not-Supported

  This card uses the Intel 82595. If it	is as ugly to use as the i82586,
  then don't count on anybody writing a	driver.


  3.19.	 LinkSys



  3.19.1.  LinkSys PCMCIA Adaptor


  Status -- Semi-Supported

  This is supposed to be a re-badged DE-650. See the information on the
  DE-650 in ``DE-650''.
  3.20.	 Microdyne



  3.20.1.  Microdyne Exos 205T


  Status -- Not-Supported

  Another i82586 based card. At	one point, dabn100@hermes.cam.ac.uk had
  written a driver that	``almost worked'' that was based on the	3c507
  code.	More details as	they are received...


  3.21.	 Mylex



  3.21.1.  Mylex LNP101, LNP104


  Status -- Semi-Supported

  These	are PCI	cards that are based on	DEC's 21040 chip. The LNP104
  uses the 21050 chip to deliver four independent 10BaseT ports. The
  standard LNP101 is selectable	between	10BaseT, 10Base2 and 10Base5
  output.  The LNP101 card should work with the	generic	21040 driver,
  but nobody has verified this yet. As for the LNP 104,	well...

  See the section on the 21040 chip (``DEC 21040'') for	more
  information.

  Mylex	can be reached at the following	numbers, in case anyone	wants to
  ask them anything.


	  MYLEX	CORPORATION, Fremont
	  Sales:  800-77-MYLEX,	(510) 796-6100
	  FAX:	  (510)	745-8016.




  3.22.	 Novell	Ethernet, NExxxx and associated	clones.


  The prefix `NE' came from Novell Ethernet. Novell followed the
  cheapest NatSemi databook design and sold the	manufacturing rights
  (spun	off?) Eagle, just to get reasonably-priced ethercards into the
  market. (The now ubiquitous NE2000 card.)


  3.22.1.  NE1000, NE2000


  Status -- Supported

  The now-generic name for a bare-bones	design around the NatSemi 8390.
  They use programmed I/O rather than shared memory, leading to	easier
  installation but slightly lower performance and a few	problems. Again,
  the savings of using an 8 bit	NE1000 over the	NE2000 are only
  warranted if you expect light	use. Some recently introduced NE2000
  clones use the National Semiconductor	`AT/LANTic' 83905 chip,	which
  offers a shared memory mode similar to the 8013 and EEPROM or	software
  configuration. Some problems can arise with poor clones. See
  ``Problems with...'',	and ``Poor NE2000 Clones'' In general it is not
  a good idea to put a NE2000 clone at I/O address 0x300 because nearly
  every	device driver probes there at boot. Some poor NE2000 clones
  don't	take kindy to being prodded in the wrong areas,	and will respond
  by locking your machine.

  Donald has written a NE2000 diagnostic program, but it is still
  presently in alpha test. (ne2k) See ``Diagnostic Programs'' for more
  information.


  3.22.2.  NE1500, NE2100


  Status -- Supported

  These	cards use the original 7990 LANCE chip from AMD	and are
  supported using the Linux lance driver.

  Some earlier versions	of the lance driver had	problems with getting
  the IRQ line via autoIRQ from	the original Novell/Eagle 7990 cards.
  Hopefully this is now	fixed.	If not,	then specify the IRQ via LILO,
  and let us know that it still	has problems.

  DMA selection	and chip numbering information can be found in ``AMD
  LANCE''.

  More technical information on	LANCE based cards can be found in
  ``Notes on AMD...''


  3.22.3.  NE3200


  Status -- Not	Supported

  This card uses a lowly 8MHz 80186, and hence you are better off using
  a cheap NE2000 clone.	Even if	a driver was available,	the NE2000 card
  would	most likely be faster.


  3.23.	 Pure Data



  3.23.1.  PDUC8028, PDI8023


  Status -- Supported

  The PureData PDUC8028	and PDI8023 series of cards are	reported to
  work,	thanks to special probe	code contributed by Mike Jagdis
  jaggy@purplet.demon.co.uk. The support is integrated with the	WD
  driver.


  3.24.	 Racal-Interlan



  3.24.1.  NI52**


  Status -- Semi-Supported

  Michael Hipp has written a driver for	this card. It is included in the
  standard kernel as an	`alpha'	driver.	Michael	would like to hear
  feedback from	users that have	this card. See ``Alpha Drivers'' for
  important information	on using alpha-test ethernet drivers with Linux.

  Michael says that ``the internal sysbus seems	to be slow. So we often
  lose packets because of overruns while receiving from	a fast remote
  host.''

  This card also uses one of the Intel chips. See ``Programming	the
  Intel	Chips''	for more technical information.



  3.24.2.  NI65**


  Status -- Semi-Supported

  There	is also	a driver for the LANCE based NI6510, and it is also
  written by Michael Hipp. Again, it is	also an	`alpha'	driver.	For some
  reason, this card is not compatible with the generic LANCE driver. See
  ``Alpha Drivers'' for	important information on using alpha-test
  ethernet drivers with	Linux.


  3.25.	 Sager



  3.25.1.  Sager NP943


  Status -- Semi-Supported

  This is just a 3c501 clone, with a different S.A. PROM prefix. I
  assume it is equally as brain	dead as	the original 3c501 as well.
  Kernels 1.1.53 and up	check for the NP943 i.d. and then just treat it
  as a 3c501 after that. See ``3Com 3c501'' for	all the	reasons	as to
  why you really don't want to use one of these	cards.


  3.26.	 Schneider & Koch



  3.26.1.  SK G16


  Status -- Supported

  This driver was included into	the v1.1 kernels, and it was written by
  PJD Weichmann	and SWS	Bern. It appears that the SK G16 is similar to
  the NI6510, in that it is based on the first edition LANCE chip (the
  7990). Once again, I have no idea as to why this card	won't work with
  the generic LANCE driver.


  3.27.	 Western Digital / SMC (Standard Microsystems Corp.)


  The ethernet part of Western Digital has been	bought by SMC.	One
  common mistake people	make is	that the relatively new	SMC Elite Ultra
  is the same as the older SMC Elite16 models -- this is not the case.

  Here is how to contact SMC (not that you should need to.)


  SMC /	Standard Microsystems Corp., 80	Arkay Drive, Hauppage,
  New York, 11788, USA.


  Technical Support via	phone:

	  800-992-4762 (USA)
	  800-433-5345 (Canada)
	  516-435-6250 (Other Countries)



  Literature requests:

	  800-SMC-4-YOU	(USA)
	  800-833-4-SMC	(Canada)
	  516-435-6255	(Other Countries)



  Technical Support via	E-mail:

	  techsupt@ccmail.west.smc.com



  FTP Site:

	  ftp.smc.com




  3.27.1.  WD8003, SMC Elite

  Status -- Supported

  These	are the	8-bit versions of the card. The	8 bit 8003 is slightly
  less expensive, but only worth the savings for light use. Note that
  some of the non-EEPROM cards (clones with jumpers, or	old old	old
  wd8003 cards)	have no	way of reporting the IRQ line used. In this
  case,	auto-irq is used, and if that fails, the driver	silently assings
  IRQ 5.  Information regarding	what the jumpers on old	non-EEPROM
  wd8003 cards do can be found in conjunction with the SMC setup/driver
  disks	stored on dorm.rutgers.edu in the directory
  /pub/novell/nic_drvs/. Note that some	of the newer SMC `SuperDisk'
  programs will	fail to	detect the old EEPROM-less cards. The file
  SMCDSK46.EXE seems to	be a good all-round choice. Also the jumper
  settings for old cards are in	an ascii text file in the aforementioned
  archive. The latest (greatest?) version can be obtained from
  ftp.smc.com.

  As these are basically the same as their 16 bit counterparts (WD8013 /
  SMC Elite16),	you should see the next	section	for more information.



  3.27.2.  WD8013, SMC Elite16


  Status -- Supported

  Over the years the design has	added more registers and an EEPROM.
  Clones usually go by the `8013' name,	and usually use	a non-EEPROM
  (jumpered) design. This part of WD has been sold to SMC, so you'll
  usually see something	like SMC/WD8013	or SMC Elite16 Plus (WD8013).
  Late model SMC cards will have two main PLCC chips on	board; the SMC
  83c690 and the SMC 83c694.  The shared memory	design makes the cards
  10-20	% faster, especially with larger packets. More importantly, from
  the driver's point of	view, it avoids	a few bugs in the programmed-I/O
  mode of the 8390, allows safe	multi-threaded access to the packet
  buffer, and it doesn't have a	programmed-I/O data register that hangs
  your machine during warm-boot	probes.

  Non-EEPROM cards that	can't just read	the selected IRQ will attempt
  auto-irq, and	if that	fails, they will silently assign IRQ 10. (8 bit
  versions will	assign IRQ 5)

  Also see ``8013 clones'' and ``8013 problems''.


  3.27.3.  SMC Elite Ultra


  Status -- Supported

  This ethercard is based on a new chip	from SMC, with a few new
  features. While it has a mode	that is	similar	to the older SMC
  ethercards, it's not compatible with the old WD80*3 drivers. However,
  in this mode it shares most of its code with the other 8390 drivers,
  while	operating somewhat faster than a WD8013	clone.

  Since	part of	the Ultra looks	like an	8013, the Ultra	probe is
  supposed to find an Ultra before the wd8013 probe has	a chance to
  mistakenly identify it.

  Std. as of 0.99pl14, and made	possible by documentation and ethercard
  loan from Duke Kamstra. If you plan on using an Ultra	with Linux send
  him a	note of	thanks to let him know that there are Linux users out
  there!

  Donald mentioed that it is possible to write a separate driver for the
  Ultra's `Altego' mode	which allows chaining transmits	at the cost of
  inefficient use of receive buffers, but that will probably not happen
  right	away.  Performance re-writes of	working	drivers	are low	priority
  unless there is some particular incentive or need.

  Bus-Master SCSI host adaptor users take note:	In the manual that ships
  with Interactive UNIX, it mentions that a bug	in the SMC Ultra will
  cause	data corruption	with SCSI disks	being run from an aha-154X host
  adaptor.  This will probably bite aha-154X compatible	cards, such as
  the BusLogic boards, and the AMI-FastDisk SCSI host adaptors as well.

  Supposedly SMC has acknowledged the problem occurs with Interactive,
  and older Windows NT drivers.	It is supposed to be a hardware	conflict
  that can be worked around in the driver design. More on this as it
  develops.

  Some Linux users with	an Ultra + aha-154X compatible cards have
  experienced data corruption, while others have not.  Donald tried this
  combination himself, and wasn't able to reproduce the	problem. You
  have been warned.


  3.27.4.  SMC 8416 (EtherEZ)


  Status -- Supported

  This card uses SMC's 83c795 chip and supports	the Plug 'n Play
  specification. It also has an	SMC Ultra compatible mode, which allows
  it to	be used	with the Linux Ultra driver.  In this compatibility
  mode,	it uses	shared memory instead of programmed i/o. Be sure to set
  your card for	this compatibility mode.

  Note that the	EtherEZ	specific checks	were added to the SMC Ultra
  driver in 1.1.84, and	hence earlier kernel versions will not handle
  these	cards correctly.



  3.27.5.  SMC 8432 PCI	(EtherPower)


  Status -- Supported

  These	cards appear to	be a basic DEC 21040 implementation, i.e. one
  big chip and a couple	of transceivers. Donald	has used one of	these
  cards	for his	development of the generic 21040 driver. Thanks	to Duke
  Kamstra, once	again, for supplying a card to do development on.  See
  ``DEC	21040''	for more details on using one of these cards, and the
  current status of the	driver.


  3.27.6.  SMC 3008


  Status -- Not	Supported

  These	8 bit cards are	based on the Fujitsu MB86950, which is an
  ancient version of the MB86965 used in the Linux at1700 driver. Russ
  says that you	could probably hack up a driver	by looking at the
  at1700.c code	and his	DOS packet driver for the Tiara	card (tiara.asm)


  3.27.7.  SMC 3016


  Status -- Not	Supported

  These	are 16bit i/o mapped 8390 cards, much similar to a generic
  NE2000 card. If you can get the specifications from SMC, then	porting
  the NE2000 driver would probably be quite easy.


  3.27.8.  SMC 9000


  Status -- Not	Supported

  These	cards are VLB cards based on the 91c92 chip. They are fairly
  expensive, and hence the demand for a	driver is pretty low at	the
  moment.


  3.28.	 Xircom


  Another group	that won't release documentation. No cards supported.
  Don't	look for any support in	the future unless they release their
  programming information. And this is highly unlikely,	as they	forbid
  you from even	reverse- engineering their drivers. If you are already
  stuck	with one, see if you can trade it off on some DOS (l)user.

  And if you just want to verify that this is the case,	you can	reach
  Xircom at 1-800-874-7875, 1-800-438-4526 or +1-818-878-7600.	They
  used to advertise that their products	"work with all network operating
  systems", but	have since stopped. Wonder why...
  3.28.1.  PE1,	PE2, PE3-10B*


  Status -- Not	Supported

  Not to get your hopes	up, but	if you have one	of these parallel port
  adaptors, you	may be able to use it in the DOS emulator with the
  Xircom-supplied DOS drivers. You will	have to	allow DOSEMU access to
  your parallel	port, and will probably	have to	play with SIG (DOSEMU's
  Silly	Interrupt Generator). I	have no	idea if	this will work,	but if
  you have any success with it,	let me know, and I will	include	it here.


  3.29.	 Zenith



  3.29.1.  Z-Note


  Status -- Supported

  The built-in Z-Note network adaptor is based on the Intel i82593 using
  two DMA channels. There is an	(alpha?) driver	available in the present
  kernel version. As with all notebook and pocket adaptors, it is under
  the `Pocket and portable adaptors' section when running make config.
  See ``Programming the	Intel chips'' for more technical information.
  Also note that the IBM ThinkPad 300 is compatible with the Z-Note.


  3.30.	 Zynx



  3.30.1.  Zynx	(DEC 21040 based)


  Status -- Supported

  You have a choice of two drivers for cards based on this chip. There
  is the DE425 driver written by David,	and the	generic	21040 driver
  that Donald has written.

  Note that as of 1.1.91, David	has added a compile time option	that may
  allow	non-DEC	cards (such as the Zynx	cards) to work with this driver.
  Have a look at README.de4x5 for details.

  See ``DEC 21040'' for	more information on these cards, and the present
  driver situation.


  4.  Clones of	popular	Ethernet cards.


  Due to the popular design of some cards, different companies will make
  `clones' or replicas of the original card. However, one must be
  careful, as some of these clones are not 100 % compatible, and can be
  troublesome. Some common problems with `not-quite-clones' are	noted in
  ``the	FAQ section''.

  This section used to have a listing of a whole bunch of clones that
  were reported	to work, but seeing as nearly all clones will work, it
  makes	more sense to list the ones that don't work 100	% .



  4.1.	Poor NE2000 Clones


  Here is a list of some of the	NE-2000	clones that are	known to have
  various problems. Most of them aren't	fatal. In the case of the ones
  listed as `bad clones' -- this usually indicates that	the cards don't
  have the two NE2000 identifier bytes.	NEx000-clones have a Station
  Address PROM (SAPROM)	in the packet buffer memory space.  NE2000
  clones have 0x57,0x57	in bytes 0x0e,0x0f of the SAPROM, while	other
  supposed NE2000 clones must be detected by their SA prefix.

  Accton NE2000	-- might not get detected at boot, see ``ne2000
  problems''.

  Aritsoft LANtastic AE-2 -- OK, but has flawed	error-reporting
  registers.

  AT-LAN-TEC NE2000 -- clone uses Winbond chip that traps SCSI drivers

  ShineNet LCS-8634 -- clone uses Winbond chip that traps SCSI drivers

  Cabletron E10**, E20**, E10**-x, E20**-x -- bad clones, but the driver
  checks for them. See ``E10**''.

  D-Link Ethernet II --	bad clones, but	the driver checks for them. See
  ``DE-100 / DE-200''.

  DFI DFINET-300, DFINET-400 --	bad clones, but	the driver checks for
  them.	See ``DFI-300 /	DFI-400''


  4.2.	Poor WD8013 Clones


  I haven't heard of any bad clones of these cards, except perhaps for
  some chamelion-type cards that can be	set to look like a ne2000 card
  or a wd8013 card. There is really no need to purchase	one of these
  `double-identity' cards anyway.


  5.  Cables, Coax, Twisted Pair

  If you are starting a	network	from scratch, it's considerably	less
  expensive to use thin	ethernet, RG58 co-ax cable with	BNC connectors,
  than old-fashioned thick ethernet, RG-5 cable	with N connectors, or
  10baseT, twisted pair	telco-style cables with	RJ-45 eight wire `phone'
  connectors. See ``Type of cable...'' for an introductory look	at
  cables.

  Also note that the FAQ from comp.dcom.lans.ethernet has a lot	of
  useful information on	cables and such. Look in dorm.rutgers.edu for
  the file /pub/novell/info_and_docs/Ethernet.FAQ


  5.1.	Thin Ethernet (thinnet)


  Thin ethernet	is the `ether of choice'. The cable is inexpensive. If
  you are making your own cables solid-core RG58A is $0.27/m. and
  stranded RG58AU is $0.45/m. Twist-on BNC connectors are < $2 ea., and
  other	misc. pieces are similarly inexpensive.	It is essential	that you
  properly terminate each end of the cable with	50 ohm terminators, so
  budget $2 ea.	for a pair. It's also vital that your cable have no
  `stubs' -- the `T' connectors	must be	attached directly to the
  ethercards. The only drawback	is that	if you have a big loop of
  machines connected together, and some	bonehead breaks	the loop by
  taking one cable off the side	of his tee, the	whole network goes down
  because it sees an infinite impedance	(open circuit) instead of the
  required 50 ohm termination. Note that you can remove	the tee	piece
  from the card	itself without killing the whole subnet, as long as you
  don't	remove the cables from the tee itself. Of course this will
  disturb the machine that you pull the	actual tee off of. 8-) And if
  you are doing	a small	network	of two machines, you still need	the tees
  and the 50 ohm terminators --	you can't just cable them together!



  5.2.	Twisted	Pair


  Twisted pair networks	require	active hubs, which start around	$200,
  and the raw cable cost can actually be higher	than thinnet. They are
  usually sold using the claim that you	can use	your existing telephone
  wiring, but it's a rare installation where that turns	out to be the
  case.	The claim that you can upgrade to higher speeds	is also	suspect,
  as most proposed schemes use higher-grade (read $$) cable and	more
  sophisticated	termination ($$$) than you would likely	install	on
  speculation. New gizmos are floating around which allow you to daisy-
  chain	machines together, and the like. For example, Farallon sells
  EtherWave adaptors and transceivers. This device allows multiple
  10baseT devices to be	daisy-chained. They also sell a	3c509 clone that
  includes the EtherWave transceiver.  The drawback is that it's more
  expensive and	less reliable than a cheap ($100-$150) mini-hub	and
  another ethercard.  You probably should either go for	the hub	approach
  or switch over to 10base2 thinnet.

  On the other hand, hubs are rapidly dropping in price, all 100Mb/sec
  ethernet proposals use twisted pair, and most	new business
  installations	use twisted pair. (This	is probably to avoid the problem
  with idiots messing with the BNC's as	described above.)

  Also,	Russ Nelson adds that `New installations should	use Category 5
  wiring. Anything else	is a waste of your installer's time, as	100Base-
  whatever is going to require Cat 5.'

  If you are only connecting two machines, it is possible to avoid using
  a hub, by swapping the Rx and	Tx pairs (1-2 and 3-6).

  If you hold the RJ-45	connector facing you (as if you	were going to
  plug it into your mouth) with	the lock tab on	the top, then the pins
  are numbered 1 to 8 from left	to right. The pin usage	is as follows:


	  Pin Number		  Assignment
	  ----------		  ----------
	  1			  Output Data (+)
	  2			  Output Data (-)
	  3			  Input	Data (+)
	  4			  Reserved for Telephone use
	  5			  Reserved for Telephone use
	  6			  Input	Data (-)
	  7			  Reserved for Telephone use
	  8			  Reserved for Telephone use



  Some cards, like the wd8013 can sense	reversed polarity, and will
  adjust accordingly. Also note	that 3 and 6 must be a twisted pair. If
  you make 3-4 a twisted pair, and 5-6 the other twisted pair, your
  cable	may work for lengths less than a metre,	but will fail miserably
  for longer lengths.

  Note that before 10BaseT was ratified	as a standard, there existed
  other	network	formats	using RJ-45 connectors,	and the	same wiring
  scheme as above. Examples are	SynOptics's LattisNet, and AT&T's
  StarLAN.  In some cases, (as with early 3C503	cards) you could set
  jumpers to get the card to talk to hubs of different types, but in
  most cases cards designed for	these older types of networks will not
  work with standard 10BaseT networks/hubs. (Note that if the cards also
  have an AUI port, then there is no reason as to why you can't	use
  that,	combined with an AUI to	10BaseT	transceiver.)


  5.3.	Thick Ethernet

  Thick	ethernet is mostly obsolete, and is usually used only to remain
  compatible with an existing implementation. You can stretch the rules
  and connect short spans of thick and thin ethernet together with a
  passive $3 N-to-BNC connector, and that's often the best solution to
  expanding an existing	thicknet. A correct (but expensive) solution is
  to use a repeater in this case.

  6.  Software Configuration and Card Diagnostics


  In most cases, if the	configuration is done by software, and stored in
  an EEPROM, you will usually have to boot DOS,	and use	the supplied DOS
  program to set the cards IRQ,	I/O, mem_addr and whatnot. Besides,
  hopefully it is something you	will only be setting once. For those
  that don't have the DOS utility available, note that a fair number of
  NIC setup/driver disks (e.g. 3Com, SMC/WD and	Allied Telesis NIC's)
  are available	from dorm.rutgers.edu in the directory
  /pub/novell/nic_drvs/	However, there are some	cards for which	Linux
  versions of the config utils exist, and they are listed here.

  Also,	Donald has written a few small card diagnostic programs	that run
  under	Linux. Most of these are a result of debugging tools that he has
  created while	writing	the various drivers. Don't expect fancy	menu-
  driven interfaces. You will have to read the source code to use most
  of these. Even if your particular card doesn't have a	corresponding
  diagnostic, you can still get	lots of	information just by typing cat
  /proc/net/dev	-- assuming that your card was at least	detected at
  boot.

  In either case, you will have	to run most of these programs as root
  (to allow I/O	to the ports) and you probably want to shut down the
  ethercard before doing so by typing ifconfig eth0 down (Note:	replace
  eth0 with atp0 or whatever when appropriate.)


  6.1.	Configuration Programs for Ethernet Cards


  For people with wd80x3 cards,	there is the program wdsetup which can
  be found in wdsetup-0.6a.tar.gz on Linux ftp sites.  I am not	sure if
  it is	being actively maintained or not, as it	has not	been updated for
  quite	a while. If it works fine for you then great, if not, use the
  DOS version that you should have got with your card. If you don't have
  the DOS version, you will be glad to know that the SMC setup/driver
  disks	are available at the dorm.rutgers.edu site mentioned above.  Of
  course, you have to have an EEPROM card to use this utility.	Old, old
  wd8003 cards,	and some wd8013	clones use jumpers to set up the card
  instead.

  The Digital EtherWorks 3 card	can be configured in a similar fashion
  to the DOS program NICSETUP.EXE. David C. Davies wrote this and other
  tools	for the	EtherWorks 3 in	conjunction with the driver. Look on
  sunsite.unc.edu in the directory /pub/linux/system/Network/management
  for the file that is named ewrk3tools-X.XX.tar.gz.

  Some Nat Semi	DP83905	implementations	(such as the AT/LANTIC and the
  NE2000+) are software	configurable. (Note that this card can also
  emulate a wd8013!) You can get the file /pub/linux/setup/atlantic.c
  from Donald's	ftp server, cesdis.gsfc.nasa.gov to configure this card.
  Be careful when configuring NE2000+ cards, as	you can	give them bad
  setting values which will require you	to open	the case and switch a
  jumper to force it back to sane settings.

  The 3Com Etherlink III family	of cards (i.e. 3c5x9) can be configured
  by using another config utility from Donald.	You can	get the	file
  /pub/linux/setup/3c5x9setup.c	from Donald's ftp server,
  cesdis.gsfc.nasa.gov to configure these cards. (Note that the	DOS
  3c5x9B config	utility	may have more options pertaining to the	new
  ``B''	series of the Etherlink	III family.)




  6.2.	Diagnostic Programs for	Ethernet Cards


  Any of the diagnostic	programs that Donald has written can be	obtained
  from this URL.

  Ethercard Diagnostics
  (http://cesdis.gsfc.nasa.gov/pub/linux/diag/diagnostic.html)

  Allied Telesis AT1700	-- look	for the	file /pub/linux/diag/at1700.c on
  cesdis.gsfc.nasa.gov.

  Cabletron E21XX -- look for the file /pub/linux/diag/e21.c on
  cesdis.gsfc.nasa.gov.

  HP PCLAN+ -- look for	the file /pub/linux/diag/hp+.c on
  cesdis.gsfc.nasa.gov.

  Intel	EtherExpress --	look for the file /pub/linux/diag/eexpress.c on
  cesdis.gsfc.nasa.gov.

  NE2000 cards -- look for the file /pub/linux/diag/ne2k.c on
  cesdis.gsfc.nasa.gov.

  RealTek (ATP)	Pocket adaptor -- look for the file /pub/linux/diag/atp-
  diag.c on cesdis.gsfc.nasa.gov.

  All Other Cards -- try typing	cat /proc/net/dev and see what useful
  info the kernel has on the card in question.


  7.  Technical	Information


  For those who	want to	play with the present drivers, or try to make up
  their	own driver for a card that is presently	unsupported, this
  information should be	useful.	If you do not fall into	this category,
  then perhaps you will	want to	skip this section.


  7.1.	Probed Addresses


  While	trying to determine what ethernet card is there, the following
  addresses are	autoprobed, assuming the type and specs	of the card have
  not been set in the kernel. The file names below are in
  /usr/src/linux/drivers/net/


  ______________________________________________________________________
	  3c501.c	  0x280, 0x300
	  3c503.c:	  0x300, 0x310,	0x330, 0x350, 0x250, 0x280, 0x2a0, 0x2e0
	  3c505.c:	  0x300, 0x280,	0x310
	  3c507.c:	  0x300, 0x320,	0x340, 0x280
	  3c509.c:	  Special ID Port probe
	  apricot.c	  0x300
	  at1700.c:	  0x300, 0x280,	0x380, 0x320, 0x340, 0x260, 0x2a0, 0x240
	  atp.c:	  0x378, 0x278,	0x3bc
	  depca.c	  0x300, 0x200
	  de600.c:	  0x378
	  de620.c:	  0x378
	  eexpress.c:	  0x300, 0x270,	0x320, 0x340
	  hp.c:		  0x300, 0x320,	0x340, 0x280, 0x2C0, 0x200, 0x240
	  hp-plus.c	  0x200, 0x240,	0x280, 0x2C0, 0x300, 0x320, 0x340
	  lance.c:	  0x300, 0x320,	0x340, 0x360
	  ne.c:		  0x300, 0x280,	0x320, 0x340, 0x360
	  ni52.c	  0x300, 0x280,	0x360, 0x320, 0x340
	  ni65.c	  0x300, 0x320,	0x340, 0x360
	  smc-ultra.c:	  0x200, 0x220,	0x240, 0x280, 0x300, 0x340, 0x380
	  wd.c:		  0x300, 0x280,	0x380, 0x240
  ______________________________________________________________________



  There	are some NE2000	clone ethercards out there that	are waiting
  black	holes for autoprobe drivers. While many	NE2000 clones are safe
  until	they are enabled, some can't be	reset to a safe	mode.  These
  dangerous ethercards will hang any I/O access	to their `dataports'.
  The typical dangerous	locations are:

  ______________________________________________________________________
	  Ethercard jumpered base     Dangerous	locations (base	+ 0x10 - 0x1f)
		  0x300	*			  0x310-0x317
		  0x320				  0x330-0x337
		  0x340				  0x350-0x357
		  0x360				  0x370-0x377
  ______________________________________________________________________



  * The	0x300 location is the traditional place	to put an ethercard, but
  it's also a popular place to put other devices (often	SCSI
  controllers).	The 0x320 location is often the	next one chosen, but
  that's bad for for the AHA1542 driver	probe. The 0x360 location is
  bad, because it conflicts with the parallel port at 0x378.  If you
  have two IDE controllers, or two floppy controlers, then 0x360 is also
  a bad	choice,	as a NE2000 card will clobber them as well.

  Note that kernels > 1.1.7X keep a log	of who uses which i/o ports, and
  will not let a driver	use i/o	ports registered by an earlier driver.
  This may result in probes silently failing.  You can view who	is using
  what i/o ports by typing cat /proc/ioports if	you have the proc
  filesystem enabled.

  To avoid these lurking ethercards, here are the things you can do:


  o  Probe for the device's BIOS in memory space. This is easy and
     always safe, but it only works for	cards that always have BIOSes,
     like primary SCSI controllers.


  o  Avoid probing any of the above locations until you	think you've
     located your device. The NE2000 clones have a reset range from
     <base>+0x18 to <base>+0x1f	that will read as 0xff,	so probe there
     first if possible.	It's also safe to probe	in the 8390 space at
     <base>+0x00 - <base>+0x0f,	but that area will return quasi-random
     values

  o  If	you must probe in the dangerous	range, for instance if your
     target device has only a few port locations, first	check that there
     isn't an NE2000 there. You	can see	how to do this by looking at the
     probe code	in /usr/src/linux/net/inet/ne.c

  o  Use the `reserve' boot time argument to protect volatile areas from
     being probed. See the information on using	boot time arguments with
     LILO in ``The reserve command''


  7.2.	Skeleton / prototype driver



  OK. So you have decided that you want	to write a driver for the Foobar
  Ethernet card, as you	have the programming information, and it hasn't
  been done yet. (...these are the two main requirements ;-) You can use
  the skeleton network driver that is provided with the	Linux kernel
  source tree. It can be found in the file
  /usr/src/linux/drivers/net/skeleton.c	as of 0.99pl15,	and later.

  It's also very useful	to look	at the Crynwr (nee Clarkson) driver for
  your target ethercard, if it's available. Russ Nelson
  nelson@crynwr.com has	been actively updating and writing these, and he
  has been very	helpful	with his code reviews of the current Linux
  drivers.


  7.3.	Driver interface to the	kernel


  Here are some	notes that may help when trying	to figure out what the
  code in the driver segments is doing,	or perhaps what	it is supposed
  to be	doing.


  ______________________________________________________________________
	  int ethif_init(struct	device *dev)
	  {
	      ...
		  dev->send_packet = &ei_send_packet;
		  dev->open = &ei_open;
		  dev->stop = &ei_close;
		  dev->hard_start_xmit = &ei_start_xmit;
		  ...
	  }

	  int ethif_init(struct	device *dev)
  ______________________________________________________________________



  This function	is put into the	device structure in Space.c. It	is
  called only at boot time, and	returns	`0' iff	the ethercard `dev'
  exists.




  ______________________________________________________________________
	  static int ei_open(struct device *dev)
	  static int ei_close(struct device *dev)
  ______________________________________________________________________



  This routine opens and initializes the board in response to an socket
  ioctl() usually called by `ifconfig'.	It is commonly stuffed into the
  `struct device' by ethif_init().

  The inverse routine is ei_close(), which should shut down the
  ethercard, free the IRQs and DMA channels if the hardware permits, and
  turn off anything that will save power (like the transceiver).


  ______________________________________________________________________
	  static int ei_start_xmit(struct sk_buff *skb,	struct device *dev)
		  dev->hard_start_xmit = &ei_start_xmit;
  ______________________________________________________________________



  This routine puts packets to be transmitted into the hardware. It is
  usually stuffed into the `struct device' by ethif_init().

  When the hardware can't accept additional packets it should set the
  dev->tbusy flag. When	additional room	is available, usually during a
  transmit-complete interrupt, dev->tbusy should be cleared and	the
  higher levels	informed with mark_bh(INET_BH).


  ______________________________________________________________________
	      if (dev_rint(buffer, length, is_skb ? IN_SKBUFF :	0, dev))
		     stats->rx_dropped++;
  ______________________________________________________________________



  A received packet is passed to the higher levels using dev_rint().  If
  the unadorned	packet data in a memory	buffer,	dev_rint will copy it
  into a `skbuff' for you. Otherwise a new skbuff should be kmalloc()ed,
  filled, and passed to	dev_rint() with	the IN_SKBUFF flag.


  ______________________________________________________________________
	  int s=socket(AF_INET,SOCK_PACKET,htons(ETH_P_ALL));
  ______________________________________________________________________



  Gives	you a socket receving every protocol type. Do recvfrom() calls
  to it	and it will fill the sockaddr with device type in sa_family and
  the device name in the sa_data array.	I don't	know who originally
  invented SOCK_PACKET for Linux (its been in for ages)	but its	superb
  stuff.  You can use it to send stuff raw too (both only as root).



  7.4.	Interrupts and Linux


  There	are two	kinds of interrupt handlers in Linux: fast ones	and slow
  ones.	You decide what	kind you are installing	by the flags you pass to
  irqaction(). The fast	ones, such as the serial interrupt handler, run
  with _all_ interrupts	disabled. The normal interrupt handlers, such as
  the one for ethercard	drivers, runs with other interrupts enabled.

  There	is a two-level interrupt structure. The	`fast' part handles the
  device register, removes the packets,	and perhaps sets a flag.  After
  it is	done, and interrupts are re-enabled, the slow part is run if the
  flag is set.

  The flag between the two parts is set	by:


       mark_bh(INET_BH);


  Usually this flag is set within dev_rint() during a received-packet
  interrupt, and set directly by the device driver during a transmit-
  complete interrupt.

  You might wonder why all interrupt handlers cannot run in `normal
  mode'	with other interrupts enabled. Ross Biro uses this scenario to
  illustrate the problem:


  o  You get a serial interrupt, and start processing it.  The serial
     interrupt is now masked.

  o  You get a network interrupt, and you start	transferring a maximum-
     sized 1500	byte packet from the card.

  o  Another character comes in, but this time the interrupts are
     masked!

  The `fast' interrupt structure solves	this problem by	allowing
  bounded-time interrupt handlers to run without the risk of leaving
  their	interrupt lines	masked by another interrupt request.

  There	is an additional distinction between fast and slow interrupt
  handlers -- the arguments passed to the handler. A `slow' handler is
  defined as


  ______________________________________________________________________

		  static void
		  handle_interrupt(int reg_ptr)
		  {
		      int irq =	-(((struct pt_regs *)reg_ptr)->orig_eax+2);
		      struct device *dev = irq2dev_map[irq];
		  ...
  ______________________________________________________________________



  While	a fast handler gets the	interrupt number directly


  ______________________________________________________________________

		  static void
		  handle_fast_interrupt(int irq)
		  {
		  ...
  ______________________________________________________________________




  A final aspect of network performance	is latency. The	only board that
  really addresses this	is the 3c509, which allows a predictive
  interrupt to be posted. It provides an interrupt response timer so
  that the driver can fine-tune	how early an interrupt is generated.

  Alan Cox has some advice for anyone wanting to write drivers that are
  to be	used with 0.99pl14 kernels and newer. He says:

  `Any driver intended for 0.99pl14 should use the new alloc_skb() and
  kfree_skbmem() functions rather than using kmalloc() to obtain a
  sk_buff. The new 0.99pl14 skeleton does this correctly. For drivers
  wishing to remain compatible with both sets the define
  `HAVE_ALLOC_SKB' indicates these functions must be used.

  In essence replace


       skb=(struct sk_buff *)kmalloc(size)


  with


       skb=alloc_skb(size)


  and


       kfree_s(skb,size)


  with


       kfree_skbmem(skb,size)  /* Only sk_buff memory though */


  Any questions	should I guess be directed to me (Alan Cox) since I made
  the change.  This is a change	to allow tracking of sk_buff's and
  sanity checks	on buffers and stack behaviour.	If a driver produces the
  message'File:	??? Line: ??? passed a non skb!' then it is probable the
  driver is not	using the new sk_buff allocators.'



  7.5.	Programmed I/O vs. Shared Memory vs. DMA


  Ethernet is 10Mbs. (Don't be pedantic, 3Mbs and 100Mbs don't count.)
  If you can already send and receive back-to-back packets, you	just
  can't	put more bits over the wire. Every modern ethercard can	receive
  back-to-back packets.	The Linux DP8390 drivers come pretty close to
  sending back-to-back packets (depending on the current interrupt
  latency) and the 3c509 and AT1500 hardware has no problem at all
  automatically	sending	back-to-back packets.

  The ISA bus can do 5.3MB/sec (42Mb/sec), which sounds	like more than
  enough. You can use that bandwidth in	several	ways:


  7.5.1.  Programmed I/O


  Pro: Doesn't use any constrained system resources, just a few	I/O
  registers, and has no	16M limit.
  Con: Usually the slowest transfer rate, the CPU is waiting the whole
  time,	and interleaved	packet access is usually difficult to
  impossible.


  7.5.2.  Shared memory


  Pro: Simple, faster than programmed I/O, and allows random access to
  packets.

  Con: Uses up memory space (a big one for DOS users, only a minor issue
  under	Linux),	and it still ties up the CPU.


  7.5.3.  Slave	(normal) Direct	Memory Access


  Pro: Frees up	the CPU	during the actual data transfer.

  Con: Checking	boundary conditions, allocating	contiguous buffers, and
  programming the DMA registers	makes it the slowest of	all techniques.
  It also uses up a scarce DMA channel,	and requires aligned low memory
  buffers.


  7.5.4.  Master Direct	Memory Access (bus-master)


  Pro: Frees up	the CPU	during the data	transfer, can string together
  buffers, can require little or no CPU	time lost on the ISA bus.

  Con: Requires	low-memory buffers and a DMA channel. Any bus-master
  will have problems with other	bus-masters that are bus-hogs, such as
  some primitive SCSI adaptors.	A few badly-designed motherboard
  chipsets have	problems with bus-masters. And a reason	for not	using
  any type of DMA device is using a Cyrix 486 processor	designed for
  plug-in replacement of a 386:	these processors must flush their cache
  with each DMA	cycle. (This includes the Cx486DLC, Ti486DLC, Cx486SLC,
  Ti486SLC, etc.)


  7.6.	Programming the	Intel chips (i82586 and	i82593)


  These	chips are used on a number of cards, namely the	3c507 ('86), the
  Intel	EtherExpress 16	('86), Microdyne's exos205t ('86), the Z-Note
  ('93), and the Racal-Interlan	ni5210 ('86).

  Russ Nelson writes: `Most boards based on the	82586 can reuse	quite a
  bit of their code.  More, in fact, than the 8390-based adapters. There
  are only three differences between them:


  o  The code to get the Ethernet address,

  o  The code to trigger CA on the 82586, and

  o  The code to reset the 82586.

  The Intel EtherExpress 16 is an exception, as	it I/O maps the	82586.
  Yes, I/O maps	it. Fairly clunky, but it works.

  Garrett Wollman did an AT&T driver for BSD that uses the BSD
  copyright. The latest	version	I have (Sep '92) only uses a single
  transmit buffer. You can and should do better	than this if you've got
  the memory. The AT&T and 3c507 adapters do; the ni5210 doesn't.

  The people at	Intel gave me a	very big clue on how you queue up
  multiple transmit packets. You set up	a list of NOP->	XMIT-> NOP->
  XMIT-> NOP-> XMIT-> beginning) blocks, then you set the `next' pointer
  of all the NOP blocks	to themselves. Now you start the command unit on
  this chain. It continually processes the first NOP block. To transmit
  a packet, you	stuff it into the next transmit	block, then point the
  NOP to it. To	transmit the next packet, you stuff the	next transmit
  block	and point the previous NOP to it. In this way, you don't have to
  wait for the previous	transmit to finish, you	can queue up multiple
  packets without any ambiguity	as to whether it got accepted, and you
  can avoid the	command	unit start-up delay.'


  7.7.	Technical information from 3Com



	  From:	Cameron	Spitzer	764-6339 <camerons@nad.3com.com	> Subject: getting 3Com	Adapter	manuals
	  Date:	Mon, 27	Sep 1993 21:17:07 +0200



  Since	this is	becoming a FAQ,	I'm going to tread the thin ice	of No
  Commercial Use and answer it here.

  3Com's Ethernet Adapters are documented for driver writers in	our
  `Technical References' (TRs).	These manuals describe the programmer
  interfaces to	the boards but they don't talk about the diagnostics,
  installation programs, etc that end users can	see.

  The Network Adapter Division marketing department has	the TRs	to give
  away.	To keep	this program efficient,	we centralized it in a thing
  called `CardFacts.' CardFacts	is an automated	phone system. You call
  it with a touch-tone phone and it faxes you stuff. To	get a TR, call
  CardFacts at 408-727-7021. Ask it for	Developer's Order Form,	document
  number 9070. Have your fax number ready when you call. Fill out the
  order	form and fax it	to 408-764-5004.  Manuals are shipped by Federal
  Express 2nd Day Service.

  If you don't have a fax and nobody you know has a fax, really	and
  truly, then send mail	to Terry_Murphy@3Mail.3Com.com and tell	her
  about	your problem.  PLEASE use the fax thing	if you possibly	can.

  After	you get	a manual, if you still can't figure out	how to program
  the board, try our `CardBoard' BBS at	1-800-876-3266,	and if you can't
  do that, write Andy_Chan@3Mail.3com.com and ask him for alternatives.
  If you have a	real stumper that nobody has figured out yet, the fellow
  who needs to know about it is	Steve_Lebus@3Mail.3com.com.

  There	are people here	who think we are too free with the manuals, and
  they are looking for evidence	that the system	is too expensive, or
  takes	too much time and effort. That's why it's important to try to
  use CardFacts	before you start calling and mailing the people	I named
  here.

  There	are even people	who think we should be like Diamond and	Xircom,
  requiring tight `partnership'	with driver writers to prevent poorly
  performing drivers from getting written. So far, 3Com	customers have
  been really good about this, and there's no problem with the level of
  requests we've been getting. We need your continued cooperation and
  restraint to keep it that way.

  Cameron Spitzer, 408-764-6339	3Com NAD Santa Clara work:
  camerons@nad.3com.com	home: cls@truffula.sj.ca.us
  7.8.	Notes on AMD PCnet / LANCE Based cards


  The AMD LANCE	(Local Area Network Controller for Ethernet) was the
  original offering, and has since been	replaced by the	`PCnet-ISA'
  chip,	otherwise known	as the 79C960.	A relatively new chip from AMD,
  the 79C960, is the heart of many new cards being released at present.
  Note that the	name `LANCE' has stuck,	and some people	will refer to
  the new chip by the old name.	Dave Roberts of	the Network Products
  Division of AMD was kind enough to contribute	the following
  information regarding	this chip:

  `As for the architecture itself, AMD developed it originally and
  reduced it to	a single chip -- the PCnet(tm)-ISA -- over a year ago.
  It's been selling like hotcakes ever since.

  Functionally,	it is equivalent to a NE1500. The register set is
  identical to the old LANCE with the 1500/2100	architecture additions.
  Older	1500/2100 drivers will work on the PCnet-ISA.  The NE1500 and
  NE2100 architecture is basically the same.  Initially	Novell called it
  the 2100, but	then tried to distinguish between coax and 10BASE-T
  cards. Anything that was 10BASE-T only was to	be numbered in the 1500
  range. That's	the only difference.

  Many companies offer PCnet-ISA based products, including HP, Racal-
  Datacom, Allied Telesis, Boca	Research, Kingston Technology, etc.  The
  cards	are basically the same except that some	manufacturers have added
  `jumperless' features	that allow the card to be configured in
  software. Most have not. AMD offers a	standard design	package	for a
  card that uses the PCnet-ISA and many	manufacturers use our design
  without change.  What	this means is that anybody who wants to	write
  drivers for most PCnet-ISA based cards can just get the data-sheet
  from AMD. Call our literature	distribution center at (800)222-9323 and
  ask for the Am79C960,	PCnet-ISA data sheet. It's free.

  A quick way to understand whether the	card is	a `stock' card is to
  just look at it. If it's stock, it should just have one large	chip on
  it, a	crystal, a small IEEE address PROM, possibly a socket for a boot
  ROM, and a connector (1, 2, or 3, depending on the media options
  offered). Note that if it's a	coax card, it will have	some transceiver
  stuff	built onto it as well, but that	should be near the connector and
  away from the	PCnet-ISA.'

  There	is also	some info regarding the	LANCE chip in the file lance.c
  which	is included in the standard kernel.

  A note to would-be card hackers is that different LANCE
  implementations do `restart' in different ways. Some pick up where
  they left off	in the ring, and others	start right from the beginning
  of the ring, as if just initialised. This is a concern when setting
  the multicast	list.


  7.9.	Multicast and Promiscuous Mode


  Another one of the things Donald has worked on is implementing
  multicast and	promiscuous mode hooks.	 All of	the released (i.e. not
  ALPHA) ISA drivers now support promiscuous mode. There was a minor
  problem with 8390 based cards	with capturing multicast packets, in
  that the promiscuous mode setting in 8390.c around line 574 should be
  0x18 and not 0x10. If	you have an up to date kernel, this will already
  be fixed.

  Donald writes: `At first I was planning to do	it while implementing
  either the /dev/* or DDI interface, but that's not really the	correct
  way to do it.	We should only enable multicast	or promiscuous modes
  when something wants to look at the packets, and shut	it down	when
  that application is finished,	neither	of which is strongly related to
  when the hardware is opened or released.

  I'll start by	discussing promiscuous mode, which is conceptually easy
  to implement.	For most hardware you only have	to set a register bit,
  and from then	on you get every packet	on the wire. Well, it's	almost
  that easy; for some hardware you have	to shut	the board (potentially
  dropping a few packet), reconfigure it, and then re-enable the
  ethercard. This is grungy and	risky, but the alternative seems to be
  to have every	application register before you	open the ethercard at
  boot-time.

  OK, so that's	easy, so I'll move on something	that's not quite so
  obvious: Multicast. It can be	done two ways:


  1. Use promiscuous mode, and a packet	filter like the	Berkeley packet
     filter (BPF). The BPF is a	pattern	matching stack language, where
     you write a program that picks out	the addresses you are interested
     in. Its advantage is that it's very general and programmable. Its
     disadvantage is that there	is no general way for the kernel to
     avoid turning on promiscuous mode and running every packet	on the
     wire through every	registered packet filter. See ``The Berkeley
     Packet Filter'' for more info.


  2. Using the built-in	multicast filter that most etherchips have.

  I guess I should list	what a few ethercards/chips provide:



	  Chip/card  Promiscuous  Multicast filter
	  ----------------------------------------
	  Seeq8001/3c501  Yes	  Binary filter	(1)
	  3Com/3c509	  Yes	  Binary filter	(1)
	  8390		  Yes	  Autodin II six bit hash (2) (3)
	  LANCE		  Yes	  Autodin II six bit hash (2) (3)
	  i82586	  Yes	  Hidden Autodin II six	bit hash (2) (4)





  1. These cards claim to have a filter, but it's a simple yes/no
     `accept all multicast packets', or	`accept	no multicast packets'.

  2. AUTODIN II	is the standard	ethernet CRC (checksum)	polynomial. In
     this scheme multicast addresses are hashed	and looked up in a hash
     table. If the corresponding bit is	enabled, this packet is
     accepted. Ethernet	packets	are laid out so	that the hardware to do
     this is trivial --	you just latch six (usually) bits from the CRC
     circuit (needed anyway for	error checking)	after the first	six
     octets (the destination address), and use them as an index	into the
     hash table	(six bits -- a 64-bit table).


  3. These chips use the six bit hash, and must	have the table computed
     and loaded	by the host. This means	the kernel must	include	the CRC
     code.


  4. The 82586 uses the	six bit	hash internally, but it	computes the
     hash table	itself from a list of multicast	addresses to accept.
  Note that none of these chips	do perfect filtering, and we still need
  a middle-level module	to do the final	filtering. Also	note that in
  every	case we	must keep a complete list of accepted multicast
  addresses to recompute the hash table	when it	changes.

  My first pass	at device-level	support	is detailed in the new outline
  driver skeleton.c

  It looks like	the following:


  ______________________________________________________________________
	  #ifdef HAVE_MULTICAST
	  static void set_multicast_list(struct	device *dev, int num_addrs,
			   void	*addrs);
	  #endif
	  .
	  .

	  ethercard_open() {
	  ...
	  #ifdef HAVE_MULTICAST
		  dev->set_multicast_list = &set_multicast_list;
	  #endif
	  ...

	  #ifdef HAVE_MULTICAST
	  /* Set or clear the multicast	filter for this	adaptor.
	     num_addrs -- -1	  Promiscuous mode, receive all	packets
	     num_addrs -- 0	  Normal mode, clear multicast list
	     num_addrs > 0	  Multicast mode, receive normal and
		  MC packets, and do best-effort filtering.
	   */
	  static void
	  set_multicast_list(struct device *dev, int num_addrs,	void *addrs)
	  {
	  ...
  ______________________________________________________________________



  Any comments,	criticism, etc.	are welcome.'


  7.10.	 The Berkeley Packet Filter (BPF)


  The general idea of the developers is	that the BPF functionality
  should not be	provided by the	kernel,	but should be in a (hopefully
  little-used) compatibility library.

  For those not	in the know: BPF (the Berkeley Packet Filter) is an
  mechanism for	specifying to the kernel networking layers what	packets
  you are interested in. It's implemented as a specialized stack
  language interpreter built into a low	level of the networking	code. An
  application passes a program written in this language	to the kernel,
  and the kernel runs the program on each incoming packet. If the kernel
  has multiple BPF applications, each program is run on	each packet.

  The problem is that it's difficult to	deduce what kind of packets the
  application is really	interested in from the packet filter program, so
  the general solution is to always run	the filter. Imagine a program
  that registers a BPF program to pick up a low	data-rate stream sent to
  a multicast address.	Most ethernet cards have a hardware multicast
  address filter implemented as	a 64 entry hash	table that ignores most
  unwanted multicast packets, so the capability	exists to make this a
  very inexpensive operation. But with the BFP the kernel must switch
  the interface	to promiscuous mode, receive _all_ packets, and	run them
  through this filter. This is work, BTW, that's very difficult	to
  account back to the process requesting the packets.


  8.  Networking with a	Laptop/Notebook	Computer


  There	are currently only a few ways to put your laptop on a network.
  You can use the SLIP code (and run at	serial line speeds); you can buy
  one of the few laptops that come with	a NE2000-compatible ethercard;
  you can get a	notebook with a	supported PCMCIA slot built-in;	you can
  get a	laptop with a docking station and plug in an ISA ethercard; or
  you can use a	parallel port Ethernet adapter such as the D-Link
  DE-600.


  8.1.	Using SLIP


  This is the cheapest solution, but by	far the	most difficult.	Also,
  you will not get very	high transmission rates. Since SLIP is not
  really related to ethernet cards, it will not	be discussed further
  here.	See the	NET-2 Howto.


  8.2.	Built in NE2000


  This solution	severely limits	your laptop choices and	is fairly
  expensive. Be	sure to	read the specifications	carefully, as you may
  find that you	will have to buy an additional non-standard transceiver
  to actually put the machine on a network. A good idea	might be to boot
  the notebook with a kernel that has ne2000 support, and make sure it
  gets detected	and works before you lay down your cash.



  8.3.	PCMCIA Support


  As this area of Linux	development is fairly young, I'd suggest that
  you join the LAPTOPS mailing channel.	See ``Mailing lists...''  which
  describes how	to join	a mailing list channel.

  Try and determine exactly what hardware you have (ie.	card
  manufacturer,	PCMCIA chip controller manufacturer) and then ask on the
  LAPTOPS channel. Regardless, don't expect things to be all that
  simple.  Expect to have to fiddle around a bit, and patch kernels,
  etc.	Maybe someday you will be able to type `make config' 8-)

  At present, the two PCMCIA chipsets that are supported are the
  Databook TCIC/2 and the intel	i82365.

  There	is a number of programs	on tsx-11.mit.edu in
  /pub/linux/packages/laptops/ that you	may find useful. These range
  from PCMCIA Ethercard	drivers	to programs that communicate with the
  PCMCIA controller chip. Note that these drivers are usually tied to a
  specific PCMCIA chip (ie. the	intel 82365 or the TCIC/2)

  For NE2000 compatible	cards, some people have	had success with just
  configuring the card under DOS, and then booting linux from the DOS
  command prompt via loadlin.


  For those that are net-surfing you can try:

  Don's	PCMCIA Stuff (http://cesdis.gsfc.nasa.gov/linux/pcmcia.html)

  Anyway, the PCMCIA driver problem isn't specific to the Linux	world.
  It's been a real disaster in the MS-DOS world. In that world people
  expect the hardware to work if they just follow the manual.  They
  might	not expect it to interoperate with any other hardware or
  software, or operate optimally, but they do expect that the software
  shipped with the product will	function. Many PCMCIA adaptors don't
  even pass this test.

  Things are looking up	for Linux users	that want PCMCIA support, as
  substantial progress is being	made. Pioneering this effort is	David
  Hinds. His latest PCMCIA support package can be obtained from	cb-
  iris.stanford.edu in the directory /pub/pcmcia/. Look	for a file like
  pcmcia-cs-X.Y.Z.tgz where X.Y.Z will be the latest version number.
  This is most likely uploaded to tsx-11.mit.edu as well.

  Note that Donald's PCMCIA enabler works as a user-level process, and
  David	Hinds' is a kernel-level solution.  You	may be best served by
  David's package as it	is much	more widely used.


  8.4.	ISA Ethercard in the Docking Station.


  Docking stations for laptops typically cost about $250 and provide two
  full-size ISA	slots, two serial and one parallel port. Most docking
  stations are powered off of the laptop's batteries, and a few	allow
  adding extra batteries in the	docking	station	if you use short ISA
  cards. You can add an	inexpensive ethercard and enjoy	full-speed
  ethernet performance.


  8.5.	Pocket / parallel port adaptors.


  The `pocket' ethernet	adaptors may also fit your need.  Until	recently
  they actually	costed more than a docking station and cheap ethercard,
  and most tie you down	with a wall-brick power	supply.	 At present, you
  can choose from the D-Link, or the RealTek adaptor.  Most other
  companies, especially	Xircom,	(see ``Xircom'') treat the programming
  information as a trade secret, so support will likely	be slow	in
  coming. (if ever!)

  Note that the	transfer speed will not	be all that great (perhaps
  100kB/s tops?) due to	the limitations	of the parallel	port interface.

  See ``DE-600 / DE-620'' and ``RealTek'' for supported	pocket adaptors.

  You can sometimes avoid the wall-brick with the adaptors by buying or
  making a cable that draws power from the laptop's keyboard port. (See
  ``keyboard power'')


  9.  Frequently Asked Questions


  Here are some	of the more frequently asked questions about using Linux
  with an Ethernet connection. Some of the more	specific questions are
  sorted on a `per manufacturer	basis'.	 However, since	this document is
  basically `old' by the time you get it, any `new' problems will not
  appear here instantly. For these, I suggest that you make efficient
  use of your newsreader. For example, nn users	would type

       nn -xX -s'3c'


  to get all the news articles in your subscribed list that have `3c' in
  the subject. (ie. 3com, 3c509, 3c503,	etc.)  The moral: Read the man
  page for your	newsreader.


  9.1.	Alpha Drivers -- Getting and Using them


  I heard that there is	an alpha driver	available for my card.	Where
  can I	get it?

  The newest of	the `new' drivers can be found on Donald's new ftp site:
  cesdis.gsfc.nasa.gov in the /pub/linux/ area.	Things change here quite
  frequently, so just look around for it.  There is still all the stuff
  on the old ftp site ftp.super.org in /pub/linux, but this is not being
  actively maintained, and hence will be of limited value to most
  people.

  As of	recent v1.1 kernels, the `useable' alpha drivers have been
  included in the standard kernel source tree. When running make config
  you will be asked if you want	to be offered ALPHA test drivers.

  Now, if it really is an alpha, or pre-alpha driver, then please treat
  it as	such. In other words, don't complain because you can't figure
  out what to do with it. If you can't figure out how to install it,
  then you probably shouldn't be testing it.  Also, if it brings your
  machine down,	don't complain.	Instead, send us a well	documented bug
  report, or even better, a patch!

  People reading this while net-surfing	may want to check out:

  Don's	Linux Home Page
  (http://cesdis.gsfc.nasa.gov/pub/linux/linux.html)

  for the latest dirt on what is new and upcoming.


  9.2.	Using More than	one Ethernet Card per Machine


  What needs to	be done	so that	Linux can run two ethernet cards?

  The hooks for	multiple ethercards are	all there.  However, note that
  only one ethercard is	auto-probed for	by default.  This avoids a lot
  of possible boot time	hangs caused by	probing	sensitive cards.

  There	are two	ways that you can enable auto-probing for the second
  (and third, and...) card. The	easiest	method is to pass boot-time
  arguments to the kernel, which is usually done by LILO.Probing for the
  second card can be achieved by using a boot-time argument as simple as
  ether=0,0,eth1. In this case eth0 and	eth1 will be assigned in the
  order	that the cards are found at boot.  Say if you want the card at
  0x300	to be eth0 and the card	at 0x280 to be eth1 then you could use


       LILO: linux ether=5,0x300,eth0 ether=15,0x280,eth1


  The ether= command accepts more than the IRQ + i/o + name shown above.
  Please have a	look at	``Passing Ethernet Arguments...''  for the full
  syntax, card specific	parameters, and	LILO tips.


  These	boot time arguments can	be made	permanent so that you don't have
  to re-enter them every time. See the LILO configuration option
  `append' in the LILO manual.

  The second way (not recommended) is to edit the file Space.c and
  replace the 0xffe0 entry for the i/o address with a zero. The	0xffe0
  entry	tells it not to	probe for that device -- replacing it with a
  zero will enable autoprobing for that	device.	 If you	really need more
  than four ethernet cards in one machine, then	you can	clone the eth3
  entry	and change eth3	to eth4.

  Note that if you are intending to use	Linux as a gateway between two
  networks, you	will have to re-compile	a kernel with IP forwarding
  enabled. Usually using an old	AT/286 with something like the `kbridge'
  software is a	better solution.

  If you are viewing this while	net-surfing, you may wish to look at a
  mini-howto Donald has	on his WWW site. Check out Multiple Ethercards
  (http://cesdis.gsfc.nasa.gov/linux/misc/multicard.html).


  9.3.	Problems with NE1000 / NE2000 cards (and clones)


  Problem: NE*000 ethercard at 0x360 doesn't get detected anymore.

  Reason: Recent kernels ( > 1.1.7X) have more sanity checks with
  respect to overlapping i/o regions. Your NE2000 card is 0x20 wide in
  i/o space, which makes it hit	the parallel port at 0x378.  Other
  devices that could be	there are the second floppy controller (if
  equipped) at 0x370 and the secondary IDE controller at 0x376--0x377.
  If the port(s) are already registered	by another driver, the kernel
  will not let the probe happen.

  Solution: Either move	your card to an	address	like 0x280, 0x340, 0x320
  or compile without parallel printer support.

  Problem: Network `goes away' every time I print something (NE2000)

  Reason: Same problem as above, but you have an older kernel that
  doesn't check	for overlapping	i/o regions. Use the same fix as above,
  and get a new	kernel while you are at	it.

  Problem: NE*000 ethercard probe at 0xNNN: 00 00 C5 ... not found.
  (invalid signature yy	zz)

  Reason: First	off, do	you have a NE1000 or NE2000 card at the	addr.
  0xNNN?  And if so, does the hardware address reported	look like a
  valid	one? If	so, then you have a poor NE*000	clone. All NE*000 clones
  are supposed to have the value 0x57 in bytes 14 and 15 of the	SA PROM
  on the card. Yours doesn't --	it has `yy zz' instead.

  Solution: The	driver (/usr/src/linux/drivers/net/ne.c) has a "Hall of
  Shame" list at about line 42.	This list is used to detect poor clones.
  For example, the DFI cards use `DFI' in the first 3 bytes of the prom,
  instead of using 0x57	in bytes 14 and	15, like they are supposed to.

  You can determine what the first 3 bytes of your card	PROM are by
  adding a line	like:


      printk("PROM prefix: %#2x	%#2x %#2x\n",SA_prom[0],SA_prom[1],SA_prom[2]);




  into the driver, right after the error message you got above,	and just
  before the "return ENXIO" at line 227.

  Reboot with this change in place, and	after the detection fails, you
  will get the three bytes from	the PROM like the DFI example above.
  Then you can add your	card to	the bad_clone_list[] at	about line 43.
  Say the above	line printed out:


       PROM prefix: 0x3F 0x2D 0x1C


  after	you rebooted. And say that the 8 bit version of	your card was
  called the "FOO-1k" and the 16 bit version the "FOO-2k". Then	you
  would	add the	following line to the bad_clone_list[]:


       {"FOO-1k", "FOO-2k", {0x3F, 0x2D, 0x1C,}},


  Note that the	2 name strings you add can be anything -- they are just
  printed at boot, and not matched against anything on the card.  You
  can also take	out the	"printk()" that	you added above, if you	want.
  It shouldn't hit that	line anymore anyway. Then recompile once more,
  and your card	should be detected.

  Problem: Errors like DMA address mismatch

  Is the chip a	real NatSemi 8390? (DP8390, DP83901, DP83902 or
  DP83905)?  If	not, some clone	chips don't correctly implement	the
  transfer verification	register. MS-DOS drivers never do error
  checking, so it doesn't matter to them.

  Are most of the messages off by a factor of 2?  If so:  Are you using
  the NE2000 in	a 16 bit slot?	Is it jumpered to use only 8 bit
  transfers?

  The Linux driver expects a NE2000 to be in a 16 bit slot. A NE1000 can
  be in	either size slot. This problem can also	occur with some	clones,
  notably D-Link 16 bit	cards, that don't have the correct ID bytes in
  the station address PROM.

  Are you running the bus faster than 8Mhz?  If	you can	change the speed
  (faster or slower), see if that makes	a difference. Most NE2000 clones
  will run at 16MHz, but some may not. Changing	speed can also mask a
  noisy	bus.

  What other devices are on the	bus?  If moving	the devices around
  changes the reliability, then	you have a bus noise problem --	just
  what that error message was designed to detect. Congratulations,
  you've probably found	the source of other problems as	well.

  Problem: The machine hangs during boot right after the `8390...'  or
  `WD....' message. Removing the NE2000	fixes the problem.

  Solution: Change your	NE2000 base address to 0x340. Alternatively, you
  can use the device registrar implemented in 0.99pl13 and later
  kernels.

  Reason: Your NE2000 clone isn't a good enough	clone. An active NE2000
  is a bottomless pit that will	trap any driver	autoprobing in its
  space. The other ethercard drivers take great	pain to	reset the NE2000
  so that it's safe, but some clones cannot be reset. Clone chips to
  watch	out for: Winbond 83C901. Changing the NE2000 to	a less-popular
  address will move it out of the way of other autoprobes, allowing your
  machine to boot.
  Problem: The machine hangs during the	SCSI probe at boot.

  Reason: It's the same	problem	as above, change the ethercard's
  address, or use the device registrar.

  Problem: The machine hangs during the	soundcard probe	at boot.

  Reason: No, that's really during the silent SCSI probe, and it's the
  same problem as above.

  Problem: Errors like eth0: DMAing conflict in	ne_block_input

  This bug came	from timer-based packet	retransmissions. If you	got a
  timer	tick _during_ a	ethercard RX interrupt,	and timer tick tried to
  retransmit a timed-out packet, you could get a conflict. Because of
  the design of	the NE2000 you would have the machine hang (exactly the
  same the NE2000-clone	boot hangs).

  Early	versions of the	driver disabled	interrupts for a long time, and
  didn't have this problem. Later versions are fixed. (ie. kernels after
  0.99p9 should	be OK.)

  Problem: NE2000 not detected at boot - no boot messages at all

  Donald writes: `A few	people have reported a problem with detecting
  the Accton NE2000.  This problem occurs only at boot-time, and the
  card is later	detected at run-time by	the identical code my (alpha-
  test)	ne2k diagnostic	program. Accton	has been very responsive, but I
  still	haven't	tracked	down what is going on. I've been unable	to
  reproduce this problem with the Accton cards we purchased. If	you are
  having this problem, please send me an immediate bug report. For that
  matter, if you have an Accton	card send me a success report, including
  the type of the motherboard. I'm especially interested in finding out
  if this problem moves	with the particular ethercard, or stays	with the
  motherboard.'

  Here are some	things to try, as they have fixed it for some people:


  o  Change the	bus speed, or just move	the card to a different	slot.

  o  Change the	`I/O recovery time' parameter in the BIOS chipset
     configuration.


  9.4.	Problems with WD80*3 cards


  Problem: A WD80*3 is falsely detected. Removing the sound or MIDI card
  eliminates the `detected' message.

  Reason: Some MIDI ports happen to produce the	same checksum as a WD
  ethercard.

  Solution: Update your	ethercard driver: new versions include an
  additional sanity check. If it is the	midi chip at 0x388 that	is
  getting detected as a	WD living at 0x380, then you could also	use:

	  LILO:	linux reserve=0x380,8



  Problem: You get messages such as the	following with your 80*3:



  eth0:	bogus packet size, status = ........  kmalloc called with impos-
  sibly	large argument (65400) eth0: Couldn't allocate sk_buff of size
  65400	eth0: receiver overrun


  Reason: There	is a shared memory problem.

  Solution: If the problem is sporadic,	you have hardware problems.
  Typical problems that	are easy to fix	are board conflicts, having
  cache	or `shadow ROM'	enabled	for that region, or running your bus
  faster than 8Mhz. There are also a surprising	number of memory
  failures on ethernet cards, so run a diagnostic program if you have
  one for your ethercard.

  If the problem is continual, and you have have to reboot to fix the
  problem, record the boot-time	probe message and mail it to
  becker@cesdis.gsfc.nasa.gov -	Take particular	note of	the shared
  memory location.

  Problem: WD80*3 will not get detected	at boot.

  Reason: Earlier versions of the Mitsumi CD-ROM (mcd) driver probe at
  0x300	will succeed if	just about anything is that I/O	location.  This
  is bad news and needs	to be a	bit more robust.  Once another driver
  registers that it `owns' an I/O location, other drivers (incl. the
  wd80x3) are `locked out' and can not probe that addr for a card.

  Solution: Recompile a	new kernel without any excess drivers that you
  aren't using,	including the above mcd	driver.	 Or try	moving your
  ethercard to a new I/O addr. Valid I/O addr. for all the cards are
  listed in ``Probed Addresses'' You can also point the	mcd driver off
  in another direction by a boot-time parameter	(via LILO) such	as:

       mcd=0x200,12


  Problem: Old wd8003 and/or jumper-settable wd8013 always get the IRQ
  wrong.

  Reason: The old wd8003 cards and jumper-settable wd8013 clones don't
  have the EEPROM that the driver can read the IRQ setting from.  If the
  driver can't read the	IRQ, then it tries to auto-IRQ to find out what
  it is. And if	auto-IRQ returns zero, then the	driver just assigns IRQ
  5 for	an 8 bit card or IRQ 10	for a 16 bit card.

  Solution: Avoid the auto-IRQ code, and tell the kernel what the IRQ
  that you have	jumpered the card to is	via a boot time	argument.  For
  example, if you are using IRQ	9, using the following should work.


       LILO: linux ether=9,0,eth0



  9.5.	Problems with 3Com cards

  Problem: The 3c503 picks IRQ N, but this is needed for some other
  device which needs IRQ N. (eg. CD ROM	driver,	modem, etc.)  Can this
  be fixed without compiling this into the kernel?

  Solution: The	3c503 driver probes for	a free IRQ line	in the order {5,
  9/2, 3, 4}, and it should pick a line	which isn't being used.	Very old
  drivers used to pick the IRQ line at boot-time, and the current driver
  (0.99pl12 and	newer) chooses when the	card is	open()/ifconfig'ed.


  Alternately, you can fix the IRQ at boot by passing parameters via
  LILO.	The following selects IRQ9, base location 0x300, <ignored
  value>, and if_port #1 (the external transceiver).


       LILO: linux ether=9,0x300,0,1,eth0


  The following	selects	IRQ3, probes for the base location, <ignored
  value>, and the default if_port #0 (the internal transceiver)


       LILO: linux ether=3,0,0,0,eth0


  Problem: 3c503: Configured interrupt number XX is out	of range.

  Reason: Whoever built	your kernel fixed the ethercard	IRQ at XX.  The
  above	is truly evil, and worse than that, it is not necessary. The
  3c503	will autoIRQ when it gets ifconfig'ed, and pick	one of IRQ{5,
  2/9, 3, 4}.

  Solution: Use	LILO as	described above, or rebuild the	kernel,	enabling
  autoIRQ by not specifying the	IRQ line.

  Problem: The supplied	3c503 drivers don't use	the AUI	(thicknet) port.
  How does one choose it over the default thinnet port?

  Solution: The	3c503 AUI port can be selected at boot-time with
  0.99pl12 and later. The selection is overloaded onto the low bit of
  the currently-unused dev->rmem_start variable, so a boot-time
  parameter of:


       LILO: linux ether=0,0,0,1,eth0


  should work. A boot line to force IRQ	5, port	base 0x300, and	use an
  external transceiver is:


       LILO: linux ether=5,0x300,0,1,eth0


  Also note that kernel	revisions 1.00 to 1.03 had an interesting
  `feature'. They would	switch to the AUI port when the	internal
  transciever failed. This is a	problem, as it will never switch back if
  for example you momentarily disconnect the cable. Kernel versions 1.04
  and newer only switch	if the very first Tx attempt fails.


  9.6.	Problems with Hewlett Packard Cards


  Problem: HP Vectra using built in AMD	LANCE chip gets	IRQ and	DMA
  wrong.

  Solution: The	HP Vectra uses a different implementation to the
  standard HP-J2405A. The `lance.c' driver used	to always use the value
  in the setup register	of an HP Lance implementation.	In the Vectra
  case it's reading an invalid 0xff value. Kernel versions newer than
  about	1.1.50 now handle the Vectra in	an appropriate fashion.

  Problem: HP Card is not detected at boot, even though	kernel was
  compiled with	`HP PCLAN support'.

  Solution: You	probably have a	HP PCLAN+  -- note the `plus'. Support
  for the PCLAN+ was added to final versions of	1.1, but some of them
  didn't have the entry	in `config.in'.	If you have the	file hp-plus.c
  in  /linux/drivers/net/ but no entry in config.in, then add the
  following line under the `HP PCLAN support' line:


	  bool 'HP PCLAN Plus support' CONFIG_HPLAN_PLUS n



  Kernels up tp	1.1.54 are missing the line in `config.in' still.  Do a
  `make	mrproper;make config;make dep;make zlilo' and you should be in
  business.


  9.7.	FAQs Not Specific to Any Card.



  9.7.1.  ifconfig reports the wrong i/o address for the card.


  No it	doesn't. You are just interpreting it incorrectly.  This is not
  a bug, and the numbers reported are correct. It just happens that some
  8390 based cards (wd80x3, smc-ultra, etc) have the actual 8390 chip
  living at an offset from the first assigned i/o port.	 Try cd
  /usr/src/linux/drivers/net;grep NIC_OFFSET *.c|more to see what is
  going	on. This is the	value stored in	dev->base_addr,	and is what
  ifconfig reports. If you want	to see the full	range of ports that your
  card uses, then try cat /proc/ioports	which will give	the numbers you
  expect.


  9.7.2.  Token	Ring

  Is there token ring support for Linux?

  To support token ring	requires more than only	a writing a device
  driver, it also requires writing the source routing routines for token
  ring.	It is the source routing that would be the most	time comsuming
  to write.

  Alan Cox adds: `It will require (...)	changes	to the bottom socket
  layer	to support 802.2 and 802.2 based TCP/IP. Don't expect anything
  soon.'

  Peter	De Schrijver has been spending some time on Token Ring lately,
  and has patches that are available for IBM ISA and MCA token ring
  cards. Don't expect miracles here, as	he has just started on this as
  of 1.1.42. You can get the patch from:

  aix13ps2.cc.kuleuven.ac.be:/pub/Linux/TokenRing.patch-1.1.49.gz



  9.7.3.  32 Bit / VLB / PCI Ethernet Cards


  What is the selection	for 32 bit ethernet cards?

  There	aren't many 32 bit ethercard device drivers because there aren't
  that many 32 bit ethercards.

  There	aren't many 32 bit ethercards out there	because	a 10Mbs	network
  doesn't justify spending the 5x price	increment for the 32 bit
  interface.  See ``Programmed I/O vs. ...'' as	to why having an
  ethercard on an 8MHz ISA bus is really not a bottleneck.

  This might change now	that AMD has introduced	the 32 bit PCnet-VLB and
  PCnet-PCI chips.  The	street price of	the Boca PCnet-VLB board should
  be under $70 from a place like CMO (see Computer Shopper).  See ``Boca
  PCI/VLB'' for	info on	these cards.

  See ``AMD PCnet-32'' for info	on the 32 bit versions of the LANCE /
  PCnet-ISA chip.

  The DEC 21040	PCI chip is another option (see	``DEC 21040'') for
  power-users.	The 21140 100Base-? chip could prove interesting as
  well,	as it is supposedly driver compatible with the 21040. Should be
  good for uncovering any race-conditions, if nothing else...


  9.7.4.  FDDI

  Is there FDDI	support	for Linux?

  Donald writes: `No, there is no Linux	driver for any FDDI boards.  I
  come from a place with supercomputers, so an external	observer might
  think	FDDI would be high on my list. But FDDI	never delivered	end-to-
  end throughput that would justify its	cost, and it seems to be a
  nearly abandoned technology now that 100base{X,Anynet} seems imminent.
  (And yes, I know you can now get FDDI	boards for <$1K. That seems to
  be a last-ditch effort to get	some return on the development
  investment. Where is the next	generation of FDDI going to come from?)'


  9.7.5.  Linking 10BaseT without a Hub


  Can I	link 10BaseT (RJ45) based systems together without a hub?

  You can link 2 machines easily, but no more than that, without extra
  devices/gizmos. See ``Twisted	Pair'' -- it explains how to do	it. And
  no, you can't	hack together a	hub just by crossing a few wires and
  stuff. It's pretty much impossible to	do the collision signal	right
  without duplicating a	hub.


  9.7.6.  SIOCSFFLAGS: Try again


  I get	`SIOCSFFLAGS: Try again' when I	run `ifconfig' -- Huh?

  Some other device has	taken the IRQ that your	ethercard is trying to
  use, and so the ethercard can't use the IRQ.	You don't necessairly
  need to reboot to resolve this, as some devices only grab the	IRQs
  when they need them and then release them when they are done.	Examples
  are some sound cards,	serial ports, floppy disk driver, etc. You can
  type cat /proc/interrupts to see which interrupts are	presently in
  use. Most of the Linux ethercard drivers only	grab the IRQ when they
  are opened for use via `ifconfig'. If	you can	get the	other device to
  `let go' of the required IRQ line, then you should be	able to	`Try
  again' with ifconfig.


  9.7.7.  Link UNSPEC and HW-addr of 00:00:00:00:00:00


  When I run ifconfig with no arguments, it reports that LINK is UNSPEC
  (instead of 10Mbs Ethernet) and it also says that my hardware	address
  is all zeros.
  This is because people are running a newer version of	the `ifconfig'
  program than their kernel version. This new version of ifconfig is not
  able to report these properties when used in conjunction with	an older
  kernel. You can either upgrade your kernel, `downgrade' ifconfig, or
  simply ignore	it. The	kernel knows your hardware address, so it really
  doesn't matter if ifconfig can't read	it.


  9.7.8.  Huge Number of RX and	TX Errors


  When I run ifconfig with no arguments, it reports that I have	a huge
  error	count in both rec'd and	transmitted packets. It	all seems to
  work ok -- What is wrong?

  Look again. It says RX packets big number PAUSE errors 0 PAUSE dropped
  0 PAUSE overrun 0.  And the same for the TX column.  Hence the big
  numbers you are seeing are the total number of packets that your
  machine has rec'd and	transmitted.  If you still find	it confusing,
  try typing cat /proc/net/dev instead.


  9.7.9.  Entries in /dev/ for Ethercards


  I have /dev/eth0 as a	link to	/dev/xxx. Is this right?

  Contrary to what you have heard, the files in	/dev/* are not used.
  You can delete any /dev/wd0, /dev/ne0	and similar entries.


  9.7.10.  Linux and ``trailers''


  Should I disable trailers when I `ifconfig' my ethercard?

  You can't disable trailers, and you shouldn't	want to. `Trailers' are
  a hack to avoid data copying in the networking layers. The idea was to
  use a	trivial	fixed-size header of size `H', put the variable-size
  header info at the end of the	packet,	and allocate all packets `H'
  bytes	before the start of a page. While it was a good	idea, it turned
  out to not work well in practice.  If	someone	suggests the use of
  `-trailers', note that it is the equivalent of sacrificial goats
  blood. It won't do anything to solve the problem, but	if problem fixes
  itself then someone can claim	deep magical knowledge.


  9.7.11.  Non-existent	Apricot	NIC is detected


  I get	eth0: Apricot 82596 at 0x300, 00 00 00 00 00 00	IRQ 10 and
  apricot.c:v.0.02 19/05/94 when I boot, but I don't have an
  ``Apricot''. And then	the card I do have isn't detected.

  A few	kernel releases	had a version of the Apricot driver which only
  used a simple	checksum to detect if an Apricot is present. This would
  mistakenly think that	almost everything was an Apricot NIC. It really
  should look at the vendor prefix instead. However there is now a check
  to see if the	hardware address is all	zeros, so this shouldn't happen.
  Your choices are to move your	card off of 0x300 (the only place the
  Apricot driver probes), or better yet, get a new kernel.





  10.  Miscellaneous.


  Any other associated stuff that didn't fit in	anywhere else gets
  dumped here. It may not be relevant, and it may not be of general
  interest but it is here anyway.


  10.1.	 Passing Ethernet Arguments to the Kernel


  Here are two generic kernel commands	that can be passed to the kernel
  at boot time.	This can be done with LILO, loadlin, or	any other
  booting utility that accepts optional	arguments.

  For exmaple, if the command was `blah' and it	expected 3 arguments
  (say 123, 456, and 789) then,	with LILO, you would use:

  LILO:	linux blah=123,456,789

  Note:	PCI cards have their i/o and IRQ assigned by the BIOS at boot.
  This means that any boot time	arguments for a	PCI card's IRQ or i/o
  ports	are ignored.


  10.1.1.  The ether command


  In its most generic form, it looks something like this:


       ether=IRQ,BASE_ADDR,PARAM_1,PARAM_2,NAME


  All arguments	are optional.  The first non-numeric argument is taken
  as the NAME.

  IRQ: Obvious.	 An IRQ	value of `0' (usually the default) means to
  autoIRQ.  It's a historical accident that the	IRQ setting is first
  rather than the base_addr -- this will be fixed whenever something
  else changes.

  BASE_ADDR: Also obvious.  A value of `0' (usually the	default) means
  to probe a card-type-specific	address	list for an ethercard.

  PARAM_1: It was orginally used as an override	value for the memory
  start	for a shared-memory ethercard, like the	WD80*3.	 Some drivers
  use the low four bits	of this	value to set the debug message level.  0
  -- default, 1-7 -- level 1..7, (7 is maximum verbosity)  8 --	level 0
  (no messages). Also, the LANCE driver	uses the low four bits of this
  value	to select the DMA channel.  Otherwise it uses auto-DMA.

  PARAM_2: The 3c503 driver uses this to select	between	the internal and
  external transceivers.  0 -- default/internal, 1 -- AUI external.  The
  Cabletron E21XX card also uses the low 4 bits	of PARAM_2 to select the
  output media.	Otherwise it detects automatically.

  NAME:	Selects	the network device the values refer to.	 The standard
  kernel uses the names	`eth0',	`eth1',	`eth2' and `eth3' for bus-
  attached ethercards, and `atp0' for the parallel port	`pocket'
  ethernet adaptor. The	arcnet driver uses `arc0' as its name.	The
  default setting is for a single ethercard to be probed for as	`eth0'.
  Multiple cards can only be enabled by	explicitly setting up their base
  address using	these LILO parameters.	The 1.0	kernel has LANCE-based
  ethercards as	a special case.	 LILO arguments	are ignored, and LANCE
  cards	are always assigned `eth<n>' names starting at `eth0'.
  Additional non-LANCE ethercards must be explicitly assigned to
  `eth<n+1>', and the usual `eth0' probe disabled with something like
  `ether=0,-1,eth0'.  (	Yes, this is bug. )


  10.1.2.  The reserve command


  This next lilo command is used just like `ether=' above, ie. it is
  appended to the name of the boot select specified in lilo.conf


       reserve=IO-base,extent{,IO-base,extent...}


  In some machines it may be necessary to prevent device drivers from
  checking for devices (auto-probing) in a specific region. This may be
  because of poorly designed hardware that causes the boot to freeze
  (such	as some	ethercards), hardware that is mistakenly identified,
  hardware whose state is changed by an	earlier	probe, or merely
  hardware you don't want the kernel to	initialize.

  The reserve boot-time	argument addresses this	problem	by specifying an
  I/O port region that shouldn't be probed. That region	is reserved in
  the kernel's port registration table as if a device has already been
  found	in that	region.	Note that this mechanism shouldn't be necessary
  on most machines. Only when there is a problem or special case would
  it be	necessary to use this.

  The I/O ports	in the specified region	are protected against device
  probes. This was put in to be	used when some driver was hanging on a
  NE2000, or misidentifying some other device as its own.  A correct
  device driver	shouldn't probe	a reserved region, unless another boot
  argument explicitly specifies	that it	do so.	This implies that
  reserve will most often be used with some other boot argument. Hence
  if you specify a reserve region to protect a specific	device,	you must
  generally specify an explicit	probe for that device. Most drivers
  ignore the port registration table if	they are given an explicit
  address.

  For example, the boot	line


       LILO: linux  reserve=0x300,32  ether=0,0x300,eth0


  keeps	all device drivers except the ethercard	drivers	from probing
  0x300-0x31f.

  As usual with	boot-time specifiers there is an 11 parameter limit,
  thus you can only specify 5 reserved regions per reserve keyword.
  Multiple reserve specifiers will work	if you have an usually
  complicated request.


  10.2.	 Using the Ethernet Drivers as Modules


  At present, all the modules are put in the subdirectory modules in
  your Linux kernel source tree	(usually in the	form of	symbolic links).
  To actually generate the modules, you	have to	type make modules after
  you have finished building the kernel	proper.	Earlier	kernels	built
  them automatically, which wasn't fair	to those compiling on 4MB
  386sx-16 machines.


  If you have an 8390 based card, you will have	to insert two modules,
  8390.o and then the module for your card.  You can find out if your
  card uses an 8390 chip by reading the	above documentation for	your
  card,	or by just typing something like grep 8390 my_card_name.c in the
  drivers/net/ directory. If grep finds	anything, then your card has an
  8390 (or compatible) chip.

  Once you have	figured	this out, you can insert the module(s) by typing
  insmod mod_name.o as root. The command lsmod will show you what
  modules are loaded, and rmmod	will remove them.

  Once a module	is inserted, then you can use it just like normal, and
  give ifconfig	commands. If you set up	your networking	at boot, then
  make sure your /etc/rc* files	run the	insmod command(s) before getting
  to the ifconfig command.

  Also note that a busy	module can't be	removed. That means that you
  will have to ifconfig	eth0 down  (shut down the ethernet card) before
  you can remove the modules. Also, if you use an 8390 based card, you
  will have to remove the card module before removing the 8390 module,
  as the 8390 module is	used by	the card module.


  10.3.	 Contributors


  Other	people who have	contributed (directly or indirectly) to	the
  Ethernet-Howto are, in alphabetical order:


	  Ross Biro		  <bir7@leland.stanford.edu>
	  Alan Cox		  <iialan@www.linux.org.uk>
	  David	C. Davies	  <davies@wanton.enet.dec.com>
	  Bjorn	Ekwall		  <bj0rn@blox.se>
	  David	Hinds		  <dhinds@allegro.stanford.edu>
	  Michael Hipp		  <mhipp@student.uni-tuebingen.de>
	  Mike Jagdis		  <jaggy@purplet.demon.co.uk>
	  Duke Kamstra		  <kamstra@ccmail.west.smc.com>
	  Russell Nelson	  <nelson@crynwr.com>
	  Cameron Spitzer	  <camerons@NAD.3Com.com>
	  Dave Roberts		  <david.roberts@amd.com>
	  Glenn	Talbott		  <gt@hprnd.rose.hp.com>




  Many thanks to the above people, and all the other unmentioned testers
  out there.


  10.4.	 Closing


  If you have found any	glaring	typos, or outdated info	in this
  document, please let one of us know. It's getting big, and it	is easy
  to overlook stuff.

  Thanks,

  Paul Gortmaker, Paul.Gortmaker@anu.edu.au

  Donald J. Becker, becker@cesdis.gsfc.nasa.gov