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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
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tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /Documentation/networking/arcnet-hardware.txt
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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+
+-----------------------------------------------------------------------------
+1) This file is a supplement to arcnet.txt. Please read that for general
+ driver configuration help.
+-----------------------------------------------------------------------------
+2) This file is no longer Linux-specific. It should probably be moved out of
+ the kernel sources. Ideas?
+-----------------------------------------------------------------------------
+
+Because so many people (myself included) seem to have obtained ARCnet cards
+without manuals, this file contains a quick introduction to ARCnet hardware,
+some cabling tips, and a listing of all jumper settings I can find. Please
+e-mail apenwarr@worldvisions.ca with any settings for your particular card,
+or any other information you have!
+
+
+INTRODUCTION TO ARCNET
+----------------------
+
+ARCnet is a network type which works in a way similar to popular Ethernet
+networks but which is also different in some very important ways.
+
+First of all, you can get ARCnet cards in at least two speeds: 2.5 Mbps
+(slower than Ethernet) and 100 Mbps (faster than normal Ethernet). In fact,
+there are others as well, but these are less common. The different hardware
+types, as far as I'm aware, are not compatible and so you cannot wire a
+100 Mbps card to a 2.5 Mbps card, and so on. From what I hear, my driver does
+work with 100 Mbps cards, but I haven't been able to verify this myself,
+since I only have the 2.5 Mbps variety. It is probably not going to saturate
+your 100 Mbps card. Stop complaining. :)
+
+You also cannot connect an ARCnet card to any kind of Ethernet card and
+expect it to work.
+
+There are two "types" of ARCnet - STAR topology and BUS topology. This
+refers to how the cards are meant to be wired together. According to most
+available documentation, you can only connect STAR cards to STAR cards and
+BUS cards to BUS cards. That makes sense, right? Well, it's not quite
+true; see below under "Cabling."
+
+Once you get past these little stumbling blocks, ARCnet is actually quite a
+well-designed standard. It uses something called "modified token passing"
+which makes it completely incompatible with so-called "Token Ring" cards,
+but which makes transfers much more reliable than Ethernet does. In fact,
+ARCnet will guarantee that a packet arrives safely at the destination, and
+even if it can't possibly be delivered properly (ie. because of a cable
+break, or because the destination computer does not exist) it will at least
+tell the sender about it.
+
+Because of the carefully defined action of the "token", it will always make
+a pass around the "ring" within a maximum length of time. This makes it
+useful for realtime networks.
+
+In addition, all known ARCnet cards have an (almost) identical programming
+interface. This means that with one ARCnet driver you can support any
+card, whereas with Ethernet each manufacturer uses what is sometimes a
+completely different programming interface, leading to a lot of different,
+sometimes very similar, Ethernet drivers. Of course, always using the same
+programming interface also means that when high-performance hardware
+facilities like PCI bus mastering DMA appear, it's hard to take advantage of
+them. Let's not go into that.
+
+One thing that makes ARCnet cards difficult to program for, however, is the
+limit on their packet sizes; standard ARCnet can only send packets that are
+up to 508 bytes in length. This is smaller than the Internet "bare minimum"
+of 576 bytes, let alone the Ethernet MTU of 1500. To compensate, an extra
+level of encapsulation is defined by RFC1201, which I call "packet
+splitting," that allows "virtual packets" to grow as large as 64K each,
+although they are generally kept down to the Ethernet-style 1500 bytes.
+
+For more information on the advantages and disadvantages (mostly the
+advantages) of ARCnet networks, you might try the "ARCnet Trade Association"
+WWW page:
+ http://www.arcnet.com
+
+
+CABLING ARCNET NETWORKS
+-----------------------
+
+This section was rewritten by
+ Vojtech Pavlik <vojtech@suse.cz>
+using information from several people, including:
+ Avery Pennraun <apenwarr@worldvisions.ca>
+ Stephen A. Wood <saw@hallc1.cebaf.gov>
+ John Paul Morrison <jmorriso@bogomips.ee.ubc.ca>
+ Joachim Koenig <jojo@repas.de>
+and Avery touched it up a bit, at Vojtech's request.
+
+ARCnet (the classic 2.5 Mbps version) can be connected by two different
+types of cabling: coax and twisted pair. The other ARCnet-type networks
+(100 Mbps TCNS and 320 kbps - 32 Mbps ARCnet Plus) use different types of
+cabling (Type1, Fiber, C1, C4, C5).
+
+For a coax network, you "should" use 93 Ohm RG-62 cable. But other cables
+also work fine, because ARCnet is a very stable network. I personally use 75
+Ohm TV antenna cable.
+
+Cards for coax cabling are shipped in two different variants: for BUS and
+STAR network topologies. They are mostly the same. The only difference
+lies in the hybrid chip installed. BUS cards use high impedance output,
+while STAR use low impedance. Low impedance card (STAR) is electrically
+equal to a high impedance one with a terminator installed.
+
+Usually, the ARCnet networks are built up from STAR cards and hubs. There
+are two types of hubs - active and passive. Passive hubs are small boxes
+with four BNC connectors containing four 47 Ohm resistors:
+
+ | | wires
+ R + junction
+-R-+-R- R 47 Ohm resistors
+ R
+ |
+
+The shielding is connected together. Active hubs are much more complicated;
+they are powered and contain electronics to amplify the signal and send it
+to other segments of the net. They usually have eight connectors. Active
+hubs come in two variants - dumb and smart. The dumb variant just
+amplifies, but the smart one decodes to digital and encodes back all packets
+coming through. This is much better if you have several hubs in the net,
+since many dumb active hubs may worsen the signal quality.
+
+And now to the cabling. What you can connect together:
+
+1. A card to a card. This is the simplest way of creating a 2-computer
+ network.
+
+2. A card to a passive hub. Remember that all unused connectors on the hub
+ must be properly terminated with 93 Ohm (or something else if you don't
+ have the right ones) terminators.
+ (Avery's note: oops, I didn't know that. Mine (TV cable) works
+ anyway, though.)
+
+3. A card to an active hub. Here is no need to terminate the unused
+ connectors except some kind of aesthetic feeling. But, there may not be
+ more than eleven active hubs between any two computers. That of course
+ doesn't limit the number of active hubs on the network.
+
+4. An active hub to another.
+
+5. An active hub to passive hub.
+
+Remember, that you can not connect two passive hubs together. The power loss
+implied by such a connection is too high for the net to operate reliably.
+
+An example of a typical ARCnet network:
+
+ R S - STAR type card
+ S------H--------A-------S R - Terminator
+ | | H - Hub
+ | | A - Active hub
+ | S----H----S
+ S |
+ |
+ S
+
+The BUS topology is very similar to the one used by Ethernet. The only
+difference is in cable and terminators: they should be 93 Ohm. Ethernet
+uses 50 Ohm impedance. You use T connectors to put the computers on a single
+line of cable, the bus. You have to put terminators at both ends of the
+cable. A typical BUS ARCnet network looks like:
+
+ RT----T------T------T------T------TR
+ B B B B B B
+
+ B - BUS type card
+ R - Terminator
+ T - T connector
+
+But that is not all! The two types can be connected together. According to
+the official documentation the only way of connecting them is using an active
+hub:
+
+ A------T------T------TR
+ | B B B
+ S---H---S
+ |
+ S
+
+The official docs also state that you can use STAR cards at the ends of
+BUS network in place of a BUS card and a terminator:
+
+ S------T------T------S
+ B B
+
+But, according to my own experiments, you can simply hang a BUS type card
+anywhere in middle of a cable in a STAR topology network. And more - you
+can use the bus card in place of any star card if you use a terminator. Then
+you can build very complicated networks fulfilling all your needs! An
+example:
+
+ S
+ |
+ RT------T-------T------H------S
+ B B B |
+ | R
+ S------A------T-------T-------A-------H------TR
+ | B B | | B
+ | S BT |
+ | | | S----A-----S
+ S------H---A----S | |
+ | | S------T----H---S |
+ S S B R S
+
+A basically different cabling scheme is used with Twisted Pair cabling. Each
+of the TP cards has two RJ (phone-cord style) connectors. The cards are
+then daisy-chained together using a cable connecting every two neighboring
+cards. The ends are terminated with RJ 93 Ohm terminators which plug into
+the empty connectors of cards on the ends of the chain. An example:
+
+ ___________ ___________
+ _R_|_ _|_|_ _|_R_
+ | | | | | |
+ |Card | |Card | |Card |
+ |_____| |_____| |_____|
+
+
+There are also hubs for the TP topology. There is nothing difficult
+involved in using them; you just connect a TP chain to a hub on any end or
+even at both. This way you can create almost any network configuration.
+The maximum of 11 hubs between any two computers on the net applies here as
+well. An example:
+
+ RP-------P--------P--------H-----P------P-----PR
+ |
+ RP-----H--------P--------H-----P------PR
+ | |
+ PR PR
+
+ R - RJ Terminator
+ P - TP Card
+ H - TP Hub
+
+Like any network, ARCnet has a limited cable length. These are the maximum
+cable lengths between two active ends (an active end being an active hub or
+a STAR card).
+
+ RG-62 93 Ohm up to 650 m
+ RG-59/U 75 Ohm up to 457 m
+ RG-11/U 75 Ohm up to 533 m
+ IBM Type 1 150 Ohm up to 200 m
+ IBM Type 3 100 Ohm up to 100 m
+
+The maximum length of all cables connected to a passive hub is limited to 65
+meters for RG-62 cabling; less for others. You can see that using passive
+hubs in a large network is a bad idea. The maximum length of a single "BUS
+Trunk" is about 300 meters for RG-62. The maximum distance between the two
+most distant points of the net is limited to 3000 meters. The maximum length
+of a TP cable between two cards/hubs is 650 meters.
+
+
+SETTING THE JUMPERS
+-------------------
+
+All ARCnet cards should have a total of four or five different settings:
+
+ - the I/O address: this is the "port" your ARCnet card is on. Probed
+ values in the Linux ARCnet driver are only from 0x200 through 0x3F0. (If
+ your card has additional ones, which is possible, please tell me.) This
+ should not be the same as any other device on your system. According to
+ a doc I got from Novell, MS Windows prefers values of 0x300 or more,
+ eating net connections on my system (at least) otherwise. My guess is
+ this may be because, if your card is at 0x2E0, probing for a serial port
+ at 0x2E8 will reset the card and probably mess things up royally.
+ - Avery's favourite: 0x300.
+
+ - the IRQ: on 8-bit cards, it might be 2 (9), 3, 4, 5, or 7.
+ on 16-bit cards, it might be 2 (9), 3, 4, 5, 7, or 10-15.
+
+ Make sure this is different from any other card on your system. Note
+ that IRQ2 is the same as IRQ9, as far as Linux is concerned. You can
+ "cat /proc/interrupts" for a somewhat complete list of which ones are in
+ use at any given time. Here is a list of common usages from Vojtech
+ Pavlik <vojtech@suse.cz>:
+ ("Not on bus" means there is no way for a card to generate this
+ interrupt)
+ IRQ 0 - Timer 0 (Not on bus)
+ IRQ 1 - Keyboard (Not on bus)
+ IRQ 2 - IRQ Controller 2 (Not on bus, nor does interrupt the CPU)
+ IRQ 3 - COM2
+ IRQ 4 - COM1
+ IRQ 5 - FREE (LPT2 if you have it; sometimes COM3; maybe PLIP)
+ IRQ 6 - Floppy disk controller
+ IRQ 7 - FREE (LPT1 if you don't use the polling driver; PLIP)
+ IRQ 8 - Realtime Clock Interrupt (Not on bus)
+ IRQ 9 - FREE (VGA vertical sync interrupt if enabled)
+ IRQ 10 - FREE
+ IRQ 11 - FREE
+ IRQ 12 - FREE
+ IRQ 13 - Numeric Coprocessor (Not on bus)
+ IRQ 14 - Fixed Disk Controller
+ IRQ 15 - FREE (Fixed Disk Controller 2 if you have it)
+
+ Note: IRQ 9 is used on some video cards for the "vertical retrace"
+ interrupt. This interrupt would have been handy for things like
+ video games, as it occurs exactly once per screen refresh, but
+ unfortunately IBM cancelled this feature starting with the original
+ VGA and thus many VGA/SVGA cards do not support it. For this
+ reason, no modern software uses this interrupt and it can almost
+ always be safely disabled, if your video card supports it at all.
+
+ If your card for some reason CANNOT disable this IRQ (usually there
+ is a jumper), one solution would be to clip the printed circuit
+ contact on the board: it's the fourth contact from the left on the
+ back side. I take no responsibility if you try this.
+
+ - Avery's favourite: IRQ2 (actually IRQ9). Watch that VGA, though.
+
+ - the memory address: Unlike most cards, ARCnets use "shared memory" for
+ copying buffers around. Make SURE it doesn't conflict with any other
+ used memory in your system!
+ A0000 - VGA graphics memory (ok if you don't have VGA)
+ B0000 - Monochrome text mode
+ C0000 \ One of these is your VGA BIOS - usually C0000.
+ E0000 /
+ F0000 - System BIOS
+
+ Anything less than 0xA0000 is, well, a BAD idea since it isn't above
+ 640k.
+ - Avery's favourite: 0xD0000
+
+ - the station address: Every ARCnet card has its own "unique" network
+ address from 0 to 255. Unlike Ethernet, you can set this address
+ yourself with a jumper or switch (or on some cards, with special
+ software). Since it's only 8 bits, you can only have 254 ARCnet cards
+ on a network. DON'T use 0 or 255, since these are reserved (although
+ neat stuff will probably happen if you DO use them). By the way, if you
+ haven't already guessed, don't set this the same as any other ARCnet on
+ your network!
+ - Avery's favourite: 3 and 4. Not that it matters.
+
+ - There may be ETS1 and ETS2 settings. These may or may not make a
+ difference on your card (many manuals call them "reserved"), but are
+ used to change the delays used when powering up a computer on the
+ network. This is only necessary when wiring VERY long range ARCnet
+ networks, on the order of 4km or so; in any case, the only real
+ requirement here is that all cards on the network with ETS1 and ETS2
+ jumpers have them in the same position. Chris Hindy <chrish@io.org>
+ sent in a chart with actual values for this:
+ ET1 ET2 Response Time Reconfiguration Time
+ --- --- ------------- --------------------
+ open open 74.7us 840us
+ open closed 283.4us 1680us
+ closed open 561.8us 1680us
+ closed closed 1118.6us 1680us
+
+ Make sure you set ETS1 and ETS2 to the SAME VALUE for all cards on your
+ network.
+
+Also, on many cards (not mine, though) there are red and green LED's.
+Vojtech Pavlik <vojtech@suse.cz> tells me this is what they mean:
+ GREEN RED Status
+ ----- --- ------
+ OFF OFF Power off
+ OFF Short flashes Cabling problems (broken cable or not
+ terminated)
+ OFF (short) ON Card init
+ ON ON Normal state - everything OK, nothing
+ happens
+ ON Long flashes Data transfer
+ ON OFF Never happens (maybe when wrong ID)
+
+
+The following is all the specific information people have sent me about
+their own particular ARCnet cards. It is officially a mess, and contains
+huge amounts of duplicated information. I have no time to fix it. If you
+want to, PLEASE DO! Just send me a 'diff -u' of all your changes.
+
+The model # is listed right above specifics for that card, so you should be
+able to use your text viewer's "search" function to find the entry you want.
+If you don't KNOW what kind of card you have, try looking through the
+various diagrams to see if you can tell.
+
+If your model isn't listed and/or has different settings, PLEASE PLEASE
+tell me. I had to figure mine out without the manual, and it WASN'T FUN!
+
+Even if your ARCnet model isn't listed, but has the same jumpers as another
+model that is, please e-mail me to say so.
+
+Cards Listed in this file (in this order, mostly):
+
+ Manufacturer Model # Bits
+ ------------ ------- ----
+ SMC PC100 8
+ SMC PC110 8
+ SMC PC120 8
+ SMC PC130 8
+ SMC PC270E 8
+ SMC PC500 16
+ SMC PC500Longboard 16
+ SMC PC550Longboard 16
+ SMC PC600 16
+ SMC PC710 8
+ SMC? LCS-8830(-T) 8/16
+ Puredata PDI507 8
+ CNet Tech CN120-Series 8
+ CNet Tech CN160-Series 16
+ Lantech? UM9065L chipset 8
+ Acer 5210-003 8
+ Datapoint? LAN-ARC-8 8
+ Topware TA-ARC/10 8
+ Thomas-Conrad 500-6242-0097 REV A 8
+ Waterloo? (C)1985 Waterloo Micro. 8
+ No Name -- 8/16
+ No Name Taiwan R.O.C? 8
+ No Name Model 9058 8
+ Tiara Tiara Lancard? 8
+
+
+** SMC = Standard Microsystems Corp.
+** CNet Tech = CNet Technology, Inc.
+
+
+Unclassified Stuff
+------------------
+ - Please send any other information you can find.
+
+ - And some other stuff (more info is welcome!):
+ From: root@ultraworld.xs4all.nl (Timo Hilbrink)
+ To: apenwarr@foxnet.net (Avery Pennarun)
+ Date: Wed, 26 Oct 1994 02:10:32 +0000 (GMT)
+ Reply-To: timoh@xs4all.nl
+
+ [...parts deleted...]
+
+ About the jumpers: On my PC130 there is one more jumper, located near the
+ cable-connector and it's for changing to star or bus topology;
+ closed: star - open: bus
+ On the PC500 are some more jumper-pins, one block labeled with RX,PDN,TXI
+ and another with ALE,LA17,LA18,LA19 these are undocumented..
+
+ [...more parts deleted...]
+
+ --- CUT ---
+
+
+** Standard Microsystems Corp (SMC) **
+PC100, PC110, PC120, PC130 (8-bit cards)
+PC500, PC600 (16-bit cards)
+---------------------------------
+ - mainly from Avery Pennarun <apenwarr@worldvisions.ca>. Values depicted
+ are from Avery's setup.
+ - special thanks to Timo Hilbrink <timoh@xs4all.nl> for noting that PC120,
+ 130, 500, and 600 all have the same switches as Avery's PC100.
+ PC500/600 have several extra, undocumented pins though. (?)
+ - PC110 settings were verified by Stephen A. Wood <saw@cebaf.gov>
+ - Also, the JP- and S-numbers probably don't match your card exactly. Try
+ to find jumpers/switches with the same number of settings - it's
+ probably more reliable.
+
+
+ JP5 [|] : : : :
+(IRQ Setting) IRQ2 IRQ3 IRQ4 IRQ5 IRQ7
+ Put exactly one jumper on exactly one set of pins.
+
+
+ 1 2 3 4 5 6 7 8 9 10
+ S1 /----------------------------------\
+(I/O and Memory | 1 1 * 0 0 0 0 * 1 1 0 1 |
+ addresses) \----------------------------------/
+ |--| |--------| |--------|
+ (a) (b) (m)
+
+ WARNING. It's very important when setting these which way
+ you're holding the card, and which way you think is '1'!
+
+ If you suspect that your settings are not being made
+ correctly, try reversing the direction or inverting the
+ switch positions.
+
+ a: The first digit of the I/O address.
+ Setting Value
+ ------- -----
+ 00 0
+ 01 1
+ 10 2
+ 11 3
+
+ b: The second digit of the I/O address.
+ Setting Value
+ ------- -----
+ 0000 0
+ 0001 1
+ 0010 2
+ ... ...
+ 1110 E
+ 1111 F
+
+ The I/O address is in the form ab0. For example, if
+ a is 0x2 and b is 0xE, the address will be 0x2E0.
+
+ DO NOT SET THIS LESS THAN 0x200!!!!!
+
+
+ m: The first digit of the memory address.
+ Setting Value
+ ------- -----
+ 0000 0
+ 0001 1
+ 0010 2
+ ... ...
+ 1110 E
+ 1111 F
+
+ The memory address is in the form m0000. For example, if
+ m is D, the address will be 0xD0000.
+
+ DO NOT SET THIS TO C0000, F0000, OR LESS THAN A0000!
+
+ 1 2 3 4 5 6 7 8
+ S2 /--------------------------\
+(Station Address) | 1 1 0 0 0 0 0 0 |
+ \--------------------------/
+
+ Setting Value
+ ------- -----
+ 00000000 00
+ 10000000 01
+ 01000000 02
+ ...
+ 01111111 FE
+ 11111111 FF
+
+ Note that this is binary with the digits reversed!
+
+ DO NOT SET THIS TO 0 OR 255 (0xFF)!
+
+
+*****************************************************************************
+
+** Standard Microsystems Corp (SMC) **
+PC130E/PC270E (8-bit cards)
+---------------------------
+ - from Juergen Seifert <seifert@htwm.de>
+
+
+STANDARD MICROSYSTEMS CORPORATION (SMC) ARCNET(R)-PC130E/PC270E
+===============================================================
+
+This description has been written by Juergen Seifert <seifert@htwm.de>
+using information from the following Original SMC Manual
+
+ "Configuration Guide for
+ ARCNET(R)-PC130E/PC270
+ Network Controller Boards
+ Pub. # 900.044A
+ June, 1989"
+
+ARCNET is a registered trademark of the Datapoint Corporation
+SMC is a registered trademark of the Standard Microsystems Corporation
+
+The PC130E is an enhanced version of the PC130 board, is equipped with a
+standard BNC female connector for connection to RG-62/U coax cable.
+Since this board is designed both for point-to-point connection in star
+networks and for connection to bus networks, it is downwardly compatible
+with all the other standard boards designed for coax networks (that is,
+the PC120, PC110 and PC100 star topology boards and the PC220, PC210 and
+PC200 bus topology boards).
+
+The PC270E is an enhanced version of the PC260 board, is equipped with two
+modular RJ11-type jacks for connection to twisted pair wiring.
+It can be used in a star or a daisy-chained network.
+
+
+ 8 7 6 5 4 3 2 1
+ ________________________________________________________________
+ | | S1 | |
+ | |_________________| |
+ | Offs|Base |I/O Addr |
+ | RAM Addr | ___|
+ | ___ ___ CR3 |___|
+ | | \/ | CR4 |___|
+ | | PROM | ___|
+ | | | N | | 8
+ | | SOCKET | o | | 7
+ | |________| d | | 6
+ | ___________________ e | | 5
+ | | | A | S | 4
+ | |oo| EXT2 | | d | 2 | 3
+ | |oo| EXT1 | SMC | d | | 2
+ | |oo| ROM | 90C63 | r |___| 1
+ | |oo| IRQ7 | | |o| _____|
+ | |oo| IRQ5 | | |o| | J1 |
+ | |oo| IRQ4 | | STAR |_____|
+ | |oo| IRQ3 | | | J2 |
+ | |oo| IRQ2 |___________________| |_____|
+ |___ ______________|
+ | |
+ |_____________________________________________|
+
+Legend:
+
+SMC 90C63 ARCNET Controller / Transceiver /Logic
+S1 1-3: I/O Base Address Select
+ 4-6: Memory Base Address Select
+ 7-8: RAM Offset Select
+S2 1-8: Node ID Select
+EXT Extended Timeout Select
+ROM ROM Enable Select
+STAR Selected - Star Topology (PC130E only)
+ Deselected - Bus Topology (PC130E only)
+CR3/CR4 Diagnostic LEDs
+J1 BNC RG62/U Connector (PC130E only)
+J1 6-position Telephone Jack (PC270E only)
+J2 6-position Telephone Jack (PC270E only)
+
+Setting one of the switches to Off/Open means "1", On/Closed means "0".
+
+
+Setting the Node ID
+-------------------
+
+The eight switches in group S2 are used to set the node ID.
+These switches work in a way similar to the PC100-series cards; see that
+entry for more information.
+
+
+Setting the I/O Base Address
+----------------------------
+
+The first three switches in switch group S1 are used to select one
+of eight possible I/O Base addresses using the following table
+
+
+ Switch | Hex I/O
+ 1 2 3 | Address
+ -------|--------
+ 0 0 0 | 260
+ 0 0 1 | 290
+ 0 1 0 | 2E0 (Manufacturer's default)
+ 0 1 1 | 2F0
+ 1 0 0 | 300
+ 1 0 1 | 350
+ 1 1 0 | 380
+ 1 1 1 | 3E0
+
+
+Setting the Base Memory (RAM) buffer Address
+--------------------------------------------
+
+The memory buffer requires 2K of a 16K block of RAM. The base of this
+16K block can be located in any of eight positions.
+Switches 4-6 of switch group S1 select the Base of the 16K block.
+Within that 16K address space, the buffer may be assigned any one of four
+positions, determined by the offset, switches 7 and 8 of group S1.
+
+ Switch | Hex RAM | Hex ROM
+ 4 5 6 7 8 | Address | Address *)
+ -----------|---------|-----------
+ 0 0 0 0 0 | C0000 | C2000
+ 0 0 0 0 1 | C0800 | C2000
+ 0 0 0 1 0 | C1000 | C2000
+ 0 0 0 1 1 | C1800 | C2000
+ | |
+ 0 0 1 0 0 | C4000 | C6000
+ 0 0 1 0 1 | C4800 | C6000
+ 0 0 1 1 0 | C5000 | C6000
+ 0 0 1 1 1 | C5800 | C6000
+ | |
+ 0 1 0 0 0 | CC000 | CE000
+ 0 1 0 0 1 | CC800 | CE000
+ 0 1 0 1 0 | CD000 | CE000
+ 0 1 0 1 1 | CD800 | CE000
+ | |
+ 0 1 1 0 0 | D0000 | D2000 (Manufacturer's default)
+ 0 1 1 0 1 | D0800 | D2000
+ 0 1 1 1 0 | D1000 | D2000
+ 0 1 1 1 1 | D1800 | D2000
+ | |
+ 1 0 0 0 0 | D4000 | D6000
+ 1 0 0 0 1 | D4800 | D6000
+ 1 0 0 1 0 | D5000 | D6000
+ 1 0 0 1 1 | D5800 | D6000
+ | |
+ 1 0 1 0 0 | D8000 | DA000
+ 1 0 1 0 1 | D8800 | DA000
+ 1 0 1 1 0 | D9000 | DA000
+ 1 0 1 1 1 | D9800 | DA000
+ | |
+ 1 1 0 0 0 | DC000 | DE000
+ 1 1 0 0 1 | DC800 | DE000
+ 1 1 0 1 0 | DD000 | DE000
+ 1 1 0 1 1 | DD800 | DE000
+ | |
+ 1 1 1 0 0 | E0000 | E2000
+ 1 1 1 0 1 | E0800 | E2000
+ 1 1 1 1 0 | E1000 | E2000
+ 1 1 1 1 1 | E1800 | E2000
+
+*) To enable the 8K Boot PROM install the jumper ROM.
+ The default is jumper ROM not installed.
+
+
+Setting the Timeouts and Interrupt
+----------------------------------
+
+The jumpers labeled EXT1 and EXT2 are used to determine the timeout
+parameters. These two jumpers are normally left open.
+
+To select a hardware interrupt level set one (only one!) of the jumpers
+IRQ2, IRQ3, IRQ4, IRQ5, IRQ7. The Manufacturer's default is IRQ2.
+
+
+Configuring the PC130E for Star or Bus Topology
+-----------------------------------------------
+
+The single jumper labeled STAR is used to configure the PC130E board for
+star or bus topology.
+When the jumper is installed, the board may be used in a star network, when
+it is removed, the board can be used in a bus topology.
+
+
+Diagnostic LEDs
+---------------
+
+Two diagnostic LEDs are visible on the rear bracket of the board.
+The green LED monitors the network activity: the red one shows the
+board activity:
+
+ Green | Status Red | Status
+ -------|------------------- ---------|-------------------
+ on | normal activity flash/on | data transfer
+ blink | reconfiguration off | no data transfer;
+ off | defective board or | incorrect memory or
+ | node ID is zero | I/O address
+
+
+*****************************************************************************
+
+** Standard Microsystems Corp (SMC) **
+PC500/PC550 Longboard (16-bit cards)
+-------------------------------------
+ - from Juergen Seifert <seifert@htwm.de>
+
+
+STANDARD MICROSYSTEMS CORPORATION (SMC) ARCNET-PC500/PC550 Long Board
+=====================================================================
+
+Note: There is another Version of the PC500 called Short Version, which
+ is different in hard- and software! The most important differences
+ are:
+ - The long board has no Shared memory.
+ - On the long board the selection of the interrupt is done by binary
+ coded switch, on the short board directly by jumper.
+
+[Avery's note: pay special attention to that: the long board HAS NO SHARED
+MEMORY. This means the current Linux-ARCnet driver can't use these cards.
+I have obtained a PC500Longboard and will be doing some experiments on it in
+the future, but don't hold your breath. Thanks again to Juergen Seifert for
+his advice about this!]
+
+This description has been written by Juergen Seifert <seifert@htwm.de>
+using information from the following Original SMC Manual
+
+ "Configuration Guide for
+ SMC ARCNET-PC500/PC550
+ Series Network Controller Boards
+ Pub. # 900.033 Rev. A
+ November, 1989"
+
+ARCNET is a registered trademark of the Datapoint Corporation
+SMC is a registered trademark of the Standard Microsystems Corporation
+
+The PC500 is equipped with a standard BNC female connector for connection
+to RG-62/U coax cable.
+The board is designed both for point-to-point connection in star networks
+and for connection to bus networks.
+
+The PC550 is equipped with two modular RJ11-type jacks for connection
+to twisted pair wiring.
+It can be used in a star or a daisy-chained (BUS) network.
+
+ 1
+ 0 9 8 7 6 5 4 3 2 1 6 5 4 3 2 1
+ ____________________________________________________________________
+ < | SW1 | | SW2 | |
+ > |_____________________| |_____________| |
+ < IRQ |I/O Addr |
+ > ___|
+ < CR4 |___|
+ > CR3 |___|
+ < ___|
+ > N | | 8
+ < o | | 7
+ > d | S | 6
+ < e | W | 5
+ > A | 3 | 4
+ < d | | 3
+ > d | | 2
+ < r |___| 1
+ > |o| _____|
+ < |o| | J1 |
+ > 3 1 JP6 |_____|
+ < |o|o| JP2 | J2 |
+ > |o|o| |_____|
+ < 4 2__ ______________|
+ > | | |
+ <____| |_____________________________________________|
+
+Legend:
+
+SW1 1-6: I/O Base Address Select
+ 7-10: Interrupt Select
+SW2 1-6: Reserved for Future Use
+SW3 1-8: Node ID Select
+JP2 1-4: Extended Timeout Select
+JP6 Selected - Star Topology (PC500 only)
+ Deselected - Bus Topology (PC500 only)
+CR3 Green Monitors Network Activity
+CR4 Red Monitors Board Activity
+J1 BNC RG62/U Connector (PC500 only)
+J1 6-position Telephone Jack (PC550 only)
+J2 6-position Telephone Jack (PC550 only)
+
+Setting one of the switches to Off/Open means "1", On/Closed means "0".
+
+
+Setting the Node ID
+-------------------
+
+The eight switches in group SW3 are used to set the node ID. Each node
+attached to the network must have an unique node ID which must be
+different from 0.
+Switch 1 serves as the least significant bit (LSB).
+
+The node ID is the sum of the values of all switches set to "1"
+These values are:
+
+ Switch | Value
+ -------|-------
+ 1 | 1
+ 2 | 2
+ 3 | 4
+ 4 | 8
+ 5 | 16
+ 6 | 32
+ 7 | 64
+ 8 | 128
+
+Some Examples:
+
+ Switch | Hex | Decimal
+ 8 7 6 5 4 3 2 1 | Node ID | Node ID
+ ----------------|---------|---------
+ 0 0 0 0 0 0 0 0 | not allowed
+ 0 0 0 0 0 0 0 1 | 1 | 1
+ 0 0 0 0 0 0 1 0 | 2 | 2
+ 0 0 0 0 0 0 1 1 | 3 | 3
+ . . . | |
+ 0 1 0 1 0 1 0 1 | 55 | 85
+ . . . | |
+ 1 0 1 0 1 0 1 0 | AA | 170
+ . . . | |
+ 1 1 1 1 1 1 0 1 | FD | 253
+ 1 1 1 1 1 1 1 0 | FE | 254
+ 1 1 1 1 1 1 1 1 | FF | 255
+
+
+Setting the I/O Base Address
+----------------------------
+
+The first six switches in switch group SW1 are used to select one
+of 32 possible I/O Base addresses using the following table
+
+ Switch | Hex I/O
+ 6 5 4 3 2 1 | Address
+ -------------|--------
+ 0 1 0 0 0 0 | 200
+ 0 1 0 0 0 1 | 210
+ 0 1 0 0 1 0 | 220
+ 0 1 0 0 1 1 | 230
+ 0 1 0 1 0 0 | 240
+ 0 1 0 1 0 1 | 250
+ 0 1 0 1 1 0 | 260
+ 0 1 0 1 1 1 | 270
+ 0 1 1 0 0 0 | 280
+ 0 1 1 0 0 1 | 290
+ 0 1 1 0 1 0 | 2A0
+ 0 1 1 0 1 1 | 2B0
+ 0 1 1 1 0 0 | 2C0
+ 0 1 1 1 0 1 | 2D0
+ 0 1 1 1 1 0 | 2E0 (Manufacturer's default)
+ 0 1 1 1 1 1 | 2F0
+ 1 1 0 0 0 0 | 300
+ 1 1 0 0 0 1 | 310
+ 1 1 0 0 1 0 | 320
+ 1 1 0 0 1 1 | 330
+ 1 1 0 1 0 0 | 340
+ 1 1 0 1 0 1 | 350
+ 1 1 0 1 1 0 | 360
+ 1 1 0 1 1 1 | 370
+ 1 1 1 0 0 0 | 380
+ 1 1 1 0 0 1 | 390
+ 1 1 1 0 1 0 | 3A0
+ 1 1 1 0 1 1 | 3B0
+ 1 1 1 1 0 0 | 3C0
+ 1 1 1 1 0 1 | 3D0
+ 1 1 1 1 1 0 | 3E0
+ 1 1 1 1 1 1 | 3F0
+
+
+Setting the Interrupt
+---------------------
+
+Switches seven through ten of switch group SW1 are used to select the
+interrupt level. The interrupt level is binary coded, so selections
+from 0 to 15 would be possible, but only the following eight values will
+be supported: 3, 4, 5, 7, 9, 10, 11, 12.
+
+ Switch | IRQ
+ 10 9 8 7 |
+ ---------|--------
+ 0 0 1 1 | 3
+ 0 1 0 0 | 4
+ 0 1 0 1 | 5
+ 0 1 1 1 | 7
+ 1 0 0 1 | 9 (=2) (default)
+ 1 0 1 0 | 10
+ 1 0 1 1 | 11
+ 1 1 0 0 | 12
+
+
+Setting the Timeouts
+--------------------
+
+The two jumpers JP2 (1-4) are used to determine the timeout parameters.
+These two jumpers are normally left open.
+Refer to the COM9026 Data Sheet for alternate configurations.
+
+
+Configuring the PC500 for Star or Bus Topology
+----------------------------------------------
+
+The single jumper labeled JP6 is used to configure the PC500 board for
+star or bus topology.
+When the jumper is installed, the board may be used in a star network, when
+it is removed, the board can be used in a bus topology.
+
+
+Diagnostic LEDs
+---------------
+
+Two diagnostic LEDs are visible on the rear bracket of the board.
+The green L