v127p9xg@ubvmsd.cc.buffalo.edu (Robert J Miskines) (12/13/90)
ISA is the 16-bit bus those of us with AT/Compatibles are familiar with.
EISA is a 32-bit bus, where the first part of the bus is ISA-compatible
if im not mistaken... But, it has an additional set of 'fingers' for an
additional 16 bits to go through.. I believe this is similar to the 8/16 bit
slots in an AT/Compatible - the first section of the 16-bit bus is
8-bit compatible.. you can plug 8-bit cards into it. If your card has the
additional 'finger set' for 16-bit work, even better.. EISA is the same way.
It will take already existing 8 and 16 bit cards, as well as 32-bit.
The whole arguement is over which interface will become 'standard', EISA or
MCA (Micro Channel Architecture), IBM's attempt to regain a mega-market share
by inventing something completely incompatible with anything already in use.
If you purchase an MCA machine, all your conventional IBM-type cards are
useless. The question - why would anyone bother with MCA? because it comes with
the IBM name. I do not KNOW, but i have heard that MCA is inferior as far as
potential for data throughput, but, since IBM invented & supports it, people
(end users, 3rd party manufacturers of add-in cards, etc) have a tendency to
support it as well.
Your decision as far as which 32-bit machine to buy will probably include the
following points..
1) Which bus will eventually win out, and what of the loser? If you invest $$$
in new machine and cards, and that bus loses out as far as standards,
you may be up the creek as far as future support..
2) If you do go MCA, remember that you will haveto replace all your current
cards. With EISA you would not have to do this. Also note that MCA cards
are more expensive than ISA cards..
As far as i know, the only 32-bit cards out yet are memory cards... Is this
true?
Robert J Miskines
V127P9XG@ubvms.cc.buffalo.edumikes@iuvax.cs.indiana.edu (Michael Squires) (12/14/90)
In article <51097@eerie.acsu.Buffalo.EDU> v127p9xg@ubvmsd.cc.buffalo.edu writes: > >As far as i know, the only 32-bit cards out yet are memory cards... Is this >true? Most memory cards are 32-bit for 386/486 systems but they are not EISA, usually proprietary. There are EISA cards from Mylex, Adaptec, and others on the market, includuing Ethernet, SCSI controllers, etc. My understanding is that they don't buy you a lot unless you're running something like 386 UNIXor 386 Novell. -- Mike Squires (mikes@iuvax.cs.indiana.edu) 812 855 3974 (w) 812 333 6564 (h) mikes@iuvax.cs.indiana.edu 546 N Park Ridge Rd., Bloomington, IN 47408 Under construction: mikes@sir-alan@cica.indiana.edu
jc58+@andrew.cmu.edu (Johnny J. Chin) (12/14/90)
Excerpts From Captions of netnews.comp.sys.ibm.pc.hardware: 13-Dec-90 Re: EISA vs. ISA Robert J Miskines@ubvmsd (1877) >ISA is the 16-bit bus those of us with AT/Compatibles are familiar with. >EISA is a 32-bit bus, where the first part of the bus is ISA-compatible >if im not mistaken... But, it has an additional set of 'fingers' for an >additional 16 bits to go through.. I believe this is similar to the 8/16 bit >slots in an AT/Compatible - the first section of the 16-bit bus is >8-bit compatible.. you can plug 8-bit cards into it. If your card has the >additional 'finger set' for 16-bit work, even better.. EISA is the same way. >It will take already existing 8 and 16 bit cards, as well as 32-bit. Sorry, but I think that you are wrong. EISA is not physically similar to ISA. EISA looks like ISA, but the 32-bit section (pins) run in between the ISA pins and are connected below the ISA pins. EISA pin connections are also narrower than ISA. From my last comparison, ISA pins are twice as wide as EISA. Don't ask me how, but the connections work. EISA slots are the same length as the 16-bit ISA slots. *** SOMEBODY PLEASE CORRECT ME IF MY MEMORY FAILS ME NOW. *** >the IBM name. I do not KNOW, but i have heard that MCA is inferior as far as >potential for data throughput, but, since IBM invented & supports it, people >(end users, 3rd party manufacturers of add-in cards, etc) have a tendency to >support it as well. MCA inferior to EISA? This is not what I've heard. I thought that MCA allows for peripheral cards to talk to each other without CPU intervention. I'm not sure that EISA can do this. Can it? >As far as i know, the only 32-bit cards out yet are memory cards... Is this >true? Not true ... they have 32-bit network cards out already. Check with Racal-Interlan (formally, Micom-Interlan; sorry, I don't have their number). __________ Carnegie Mellon University ___ / \ / / /_/ / /\/ _/ / / / "Happy Computing ..." __/. /__ / / / / / / / / -- Computer Dr. / / Internet: Johnny.J.Chin@andrew.cmu.edu / ------- / 4730 Centre Ave. #412 BITnet: jc58@andrew \__________/ Pittsburgh, PA 15213 UUCP: ...!uunet!andrew.cmu.edu!jc58
crouse@eng.umd.edu (Gil Crouse) (12/14/90)
In article <obO0GSq00UzxA3Q64_@andrew.cmu.edu> jc58+@andrew.cmu.edu (Johnny J. Chin) writes: >Excerpts From Captions of netnews.comp.sys.ibm.pc.hardware: >13-Dec-90 Re: EISA vs. ISA Robert J Miskines@ubvmsd (1877) >>ISA is the 16-bit bus those of us with AT/Compatibles are familiar with. >>EISA is a 32-bit bus, where the first part of the bus is ISA-compatible >>if im not mistaken... But, it has an additional set of 'fingers' for an >>additional 16 bits to go through.. I believe this is similar to the 8/16 bit >>slots in an AT/Compatible - the first section of the 16-bit bus is >>8-bit compatible.. you can plug 8-bit cards into it. If your card has the >>additional 'finger set' for 16-bit work, even better.. EISA is the same way. >>It will take already existing 8 and 16 bit cards, as well as 32-bit. > >Sorry, but I think that you are wrong. EISA is not physically similar to ISA. >EISA looks like ISA, but the 32-bit section (pins) run in between the ISA pins >and are connected below the ISA pins. EISA pin connections are also narrower >than ISA. From my last comparison, ISA pins are twice as wide as EISA. Don't >ask me how, but the connections work. EISA slots are the same length as the >16-bit ISA slots. > >*** SOMEBODY PLEASE CORRECT ME IF MY MEMORY FAILS ME NOW. *** > > __________ Carnegie Mellon University ___ > / \ / / /_/ / /\/ > _/ / / / "Happy Computing ..." __/. /__ / / / / / > / / / -- Computer Dr. > / / Internet: Johnny.J.Chin@andrew.cmu.edu >/ ------- / 4730 Centre Ave. #412 BITnet: jc58@andrew >\__________/ Pittsburgh, PA 15213 UUCP: ...!uunet!andrew.cmu.edu!jc58 Sorry, Mr. Chin but the original poster is correct. An EISA bus is downward compatible with ISA cards. The EISA connectors are narrower than ISA connectors and run between them as you describe, but both will function. Gil Crouse crouse@eng.umd.edu (301) 405-1140
raster@pawl.rpi.edu (Jerry D Bain) (12/14/90)
jc58+@andrew.cmu.edu (Johnny J. Chin) writes: >Excerpts From Captions of netnews.comp.sys.ibm.pc.hardware: >Sorry, but I think that you are wrong. EISA is not physically similar to ISA. >EISA looks like ISA, but the 32-bit section (pins) run in between the ISA pins >and are connected below the ISA pins. EISA pin connections are also narrower >than ISA. From my last comparison, ISA pins are twice as wide as EISA. Don't >ask me how, but the connections work. EISA slots are the same length as the >16-bit ISA slots. Actually, EISA slots have *two* layers of connectors. The first layer of contacts are ISA compatible. This makes the EISA bus ISA compatible. FULLY If a card wants to support the EISA extensions (32 bits, bus mastering), it has an extra set of gaps in the card-edge connector (like the single gap in a regular 16bit card) that allows it to reach all the way down into the second set of EISA control lines. This gives the EISA cards a funny look since they look like they have two rows of contacts. Inside an EISA board-connector though there are a matching set of doubled connectors for them. >MCA inferior to EISA? This is not what I've heard. I thought that MCA allows >for peripheral cards to talk to each other without CPU intervention. I'm not >sure that EISA can do this. Can it? The EISA standard can run at a much higher transfer rate than the MCA standard can. It supports all the functionality of the MCA bus without being tied the the IBM-proprietary patents. If memory serves, MCA runs at only 20mbit/s while EISA runs at 32mbit/s. EISA *does* support bus-mastering. There are many boards on the market already that fully support the EISA bus.
dave@interlan.Interlan.COM (Dave Goldblatt) (12/14/90)
In article <T_G^GX#@rpi.edu> raster@pawl.rpi.edu (Jerry D Bain) writes: Actually, EISA slots have *two* layers of connectors. The first layer of contacts are ISA compatible. This makes the EISA bus ISA compatible. FULLY If a card wants to support the EISA extensions (32 bits, bus mastering), it has an extra set of gaps in the card-edge connector (like the single gap in a regular 16bit card) that allows it to reach all the way down into the second set of EISA control lines. Correct. The second row of fingers is located between the gaps of the upper row; this second set of fingers are approximately two-thirds the size of the normal ISA fingers. > MCA inferior to EISA? This is not what I've heard. I thought > that MCA allows for peripheral cards to talk to each other without CPU > intervention. I'm not sure that EISA can do this. Can it? The EISA standard can run at a much higher transfer rate than the MCA standard can. It supports all the functionality of the MCA bus without being tied the the IBM-proprietary patents. If memory serves, MCA runs at only 20mbit/s while EISA runs at 32mbit/s. Partially correct. I think EISA can run 33MB/s, but IBM recently announced new "features" in MCA that can push it up to 64MB/s; I seem to recall they were going to do this with some funky design, but I don't remember the details. EISA *does* support bus-mastering. There are many boards on the market already that fully support the EISA bus. Correct. Although "many" is probably an overstatement; there aren't all that many out there yet. As someone mentioned, we have a 32-bit EISA adapter. It's fast. Really fast. In fact, one board can load 100% of the network. (Warning to parents: Don't let your children do this on a corporate LAN.) :-) It also supports Type-C DMA. There are a number of other network adapters announced, but I haven't seen any myself. By the way, you can do bus mastering on (most) ATs, too. IBM claimed otherwise, but we (and others) proved them wrong.. ;-) My personal preference? (if anyone cares ;-) EISA. MCA's improved performance was the excuse IBM used to try to regain its control over the PC market. EISA was the industry's response. I haven't seen an ISA board yet which doesn't work in an EISA machine (which conformed to the EISA spec, of course). That to me is the biggest reason to invest in an EISA box -- you don't have to immediately run out and dump all of your existing hardware -- at some point you'll probably want to, but it's at your leisure. Note: The opinions reflected herein are solely mine, and were brought to you by a lack of sleep. -dg- -- "You can twist perceptions * Dave Goldblatt [dave@interlan.com] Reality won't budge..." * Diagnostic Engineering - Rush * Racal InterLan * Boxborough MA (508) 263-9929
davidsen@sixhub.UUCP (Wm E. Davidsen Jr) (12/15/90)
In article <51097@eerie.acsu.Buffalo.EDU> v127p9xg@ubvmsd.cc.buffalo.edu writes: | 2) If you do go MCA, remember that you will haveto replace all your current | cards. With EISA you would not have to do this. Also note that MCA cards | are more expensive than ISA cards.. This is true, but after looking at what people do when they buy a new system (as opposed to an upgrade), I think most people buy what they need new rather than use old boards and break up an existing system. Specialty boards are an exception, and some people cut corners, but in general that's true. | As far as i know, the only 32-bit cards out yet are memory cards... Is this | true? No. There are disk controllers and video boards out, although I'm not sure that typical use gets much out of the video board. The 32 bit path on a smart disk controller is a BIG win. -- bill davidsen - davidsen@sixhub.uucp (uunet!crdgw1!sixhub!davidsen) sysop *IX BBS and Public Access UNIX moderator of comp.binaries.ibm.pc and 80386 mailing list "Stupidity, like virtue, is its own reward" -me
davidsen@sixhub.UUCP (Wm E. Davidsen Jr) (12/15/90)
In article <obO0GSq00UzxA3Q64_@andrew.cmu.edu> jc58+@andrew.cmu.edu (Johnny J. Chin) writes: | Sorry, but I think that you are wrong. EISA is not physically similar to ISA. | *** SOMEBODY PLEASE CORRECT ME IF MY MEMORY FAILS ME NOW. *** You got it. ISA boards drop right in. A stop prevents them from going all the way down to the EISA buss connections. -- bill davidsen - davidsen@sixhub.uucp (uunet!crdgw1!sixhub!davidsen) sysop *IX BBS and Public Access UNIX moderator of comp.binaries.ibm.pc and 80386 mailing list "Stupidity, like virtue, is its own reward" -me
davidsen@sixhub.UUCP (Wm E. Davidsen Jr) (12/15/90)
In article <obO0GSq00UzxA3Q64_@andrew.cmu.edu> jc58+@andrew.cmu.edu (Johnny J. Chin) writes: | MCA inferior to EISA? This is not what I've heard. I thought that MCA allows | for peripheral cards to talk to each other without CPU intervention. I'm not | sure that EISA can do this. Can it? EISA allows another board to be temporary master (or DMA if you like). Even the 15 year old S-100 (IEEE 696) bus allows this, I've got a system sitting here which does it. MCA does it another way, but I don't see it as better. Even the AT bus will do it, although it's not a design feature. I *think* the Adaptek 1542 SCSI controller does this, but I don't have a spec handy. Someone will correct me if I'm wrong... -- bill davidsen - davidsen@sixhub.uucp (uunet!crdgw1!sixhub!davidsen) sysop *IX BBS and Public Access UNIX moderator of comp.binaries.ibm.pc and 80386 mailing list "Stupidity, like virtue, is its own reward" -me
smasters@gmuvax2.gmu.edu (Shawn Masters) (12/15/90)
The original design of ISA, as defined by IBM, allows bus mastering. This is done by requesting the DMA, and then holding a MASTER line, until mastership is acknowledged. The card then had FULL access to all signals on the card edge(note: lines like IRQ0 and others are still CPU only lines, which means the interrupts serviced are only those of I/O devices). The limitations, all motherboard activity is stopped, including memory refresh. This means don't be a master for more then a couple microseconds or you lose trust in memory contents(although I've extenend my refresh on a 16MHz 286 upto 3 times a second with only a infrequent error. Note though that I was using REALLY fast chips, which may allow for less leakage. Not being a solid state specialist I don't know what realtionship is). Shawn Masters CNS George Mason University smasters@gmuvax2.gmu.edu
bill@bilver.uucp (Bill Vermillion) (12/16/90)
In article <51097@eerie.acsu.Buffalo.EDU> v127p9xg@ubvmsd.cc.buffalo.edu writes: > >If you purchase an MCA machine, all your conventional IBM-type cards are >useless. The question - why would anyone bother with MCA? because it comes with >the IBM name. I do not KNOW, but i have heard that MCA is inferior as far as >potential for data throughput, but, since IBM invented & supports it, people >(end users, 3rd party manufacturers of add-in cards, etc) have a tendency to >support it as well. MCA machines come with about a dozen different names on them as of this moment, including Tandy, NCR, ALR and other. As to inferior data throughput, you are mistaken. ALR is one of the few manufacturers that uses both and EISA bus and an MCA bus. Take a look at their specs for their 25Mhz 486 machines. THey are vitually identical except for the bus structure. The MCA machine has about two times the throughput of the EISA. Why? Take a look at the EISA which is limited to the 32 bits, and look at ALR's implementation of MCA, 64 bit wide bus. Not that this is pertinent to the discussion but the MCA bus on IBMs RS/6000 series (in some models) uses a buss that is 128 bits (16 bytes) wide. THere are places where an MCA bus has it's advantages. -- Bill Vermillion - UUCP: uunet!tarpit!bilver!bill : bill@bilver.UUCP
amichiel@rodan.acs.syr.edu (Allen J Michielsen) (12/16/90)
In article <2636@sixhub.UUCP> davidsen@sixhub.UUCP (bill davidsen) writes: >In article <51097@eerie.acsu.Buffalo.EDU> v127p9xg@ubvmsd.cc.buffalo.edu >| 2) If you do go MCA, remember that you will haveto replace all your current >| cards. With EISA you would not have to do this. Also note that MCA cards >| are more expensive than ISA cards.. > > This is true, but after looking at what people do when they buy a new >system (as opposed to an upgrade), I think most people buy what they >need new rather than use old boards and break up an existing system. >Specialty boards are an exception, and some people cut corners, but in >general that's true. While I agree in you generally,... 1. I feel it is VERY common for any system to have 1 add in card. (2400 baud modem, special modem, 9600 baud modem, fax modem, IEEE-488, I/O) 2. Most people would be comparing the cost of a clone (cheap--generallly) to IBM (expensive--always), and while a MMNP modem with 7 year warr can be had in ISA form for possibly $100, the cheapest, rated mca modem pc magazine tested for the mcs bus was $ 500. This difference is serious,... I feel that the extra $400 would probably turn the tide making the choice of a 'real thing' just too expensive. 3. Most people that do buy IBM's, either because of the name or because of the advanced features of the MCA bus are having their money stolen from them. The advantages of the MCA bus are many, BUT for a average user & especially a home user, the cost difference isn't worth it at all. al -- Al. Michielsen, Mechanical & Aerospace Engineering, Syracuse University InterNet: amichiel@rodan.acs.syr.edu amichiel@sunrise.acs.syr.edu Bitnet: AMICHIEL@SUNRISE
feustel@netcom.UUCP (David Feustel) (12/17/90)
Even if the MCA system were a better deal than EISA, you still would be taking on the problem of dealing with IBM whenever you had a problem or needed info. This is NOT something that home users want to take on (Speaking from experience both INSIDE and outside of the IBM corporate shell). I'm not knocking dealers either; they have exactly the same problem, but usually only slightly better contacts with IBM. -- David Feustel, 1930 Curdes Ave, Fort Wayne, IN 46805, (219) 482-9631 EMAIL: netcom.uucp
davidsen@sixhub.UUCP (Wm E. Davidsen Jr) (12/22/90)
In theory the MCA bus has a small advantage over the EISA. And the
EISA has an advantage over the ISA. Now ask yourself what you are going
to do (in the lifetime of the motherboard) which will use the extra
bandwidth. Then buy ISA in most cases.
For a single CPU application, using a single disk controller and no
more than two drives, and any display using the ISA bus, the faster
busses make no ecconomic sense.
Unless you are going to to use the bandwidth anything beyond ISA does
as much good as a six lane highway for a motorcycle at 2am. Anything you
can't *use* brings no benefit.
There are people with applications which have multiple CPUs, or
controllers, or special bus master peripheral boards, which may benefit
from these busses. Unless you are doing something special, save your money.
--
bill davidsen - davidsen@sixhub.uucp (uunet!crdgw1!sixhub!davidsen)
sysop *IX BBS and Public Access UNIX
moderator of comp.binaries.ibm.pc and 80386 mailing list
"Stupidity, like virtue, is its own reward" -mefmgst@unix.cis.pitt.edu (Filip Gieszczykiewicz) (02/09/91)
Greetings. Well, after doing my homework with the Computer Shopper (more posts to follow :-), I have come to the conclusion that it's not worth buying a 386 when you can get a 486 for ~$400 or so more. I think that I know the following ;-) : 1) 486/25 is about as fast/faster then a 386/33 2) more on-motherboard memory is possible on a 486 then 386 3) ROM shadowing and other "cute" features make a 486 even faster 4) no need to buy a 387 (more to follow as I do more homework :-) Now, what I don't know is: 1) Cyrix and ITT claim that their 387-clones are "up to 80%" faster then the Intel 80387. Is that true of the 486 also? (ie. is the 387 on-board of the 486 200% SLOWER than a clone) 2) I have heard that I can take an AT card (16-bit) and plug it into the EISA buss. True? If so, will it slow down the other EISA cards? (Like plugging in a MDA into a 16-bit-VGA system) 3) Are there any EISA VGA cards out there? (Like an EISA version of the ProDesigner II, or others) If so, are they faster? 4) Is there an EISA IDE hard disk controller? I have some IDE drives and I want to use them in my new system. Yes? Also, if I have to get a new drive, should I stick with SCSI-2 or ESDI? (I heard that SCSI-s sucks) 5) How would I, say, add a tape backup? I realize that there are 2 types, one that hooks up to a floppy drive controller and one that comes with its own card. (#2 applies to the second). Will the EISA floppy/hard controller allow for this? (I want 1.2MB and 1.44MB as a base) does it have more connectors? If I get the type with a card, will I be able to use it with my system? (see #2) That's all, for now. I will archive any responses bacuse, I have a feeling, more people will be asking these question later this year or the next. Please reply via e-mail. Take care. -- _______________________________________________________________________________ "The Force will be with you, always." It _is_ with me and has been for 10 years Filip Gieszczykiewicz "... a Jedi does it with a mind trick... " ;-) FMGST@PITTVMS or fmgst@unix.cis.pitt.edu "My ideas. ALL MINE!!"
davidsen@sixhub.UUCP (Wm E. Davidsen Jr) (02/11/91)
In article <89696@unix.cis.pitt.edu> fmgst@unix.cis.pitt.edu (Filip Gieszczykiewicz) writes: | 1) Cyrix and ITT claim that their 387-clones are "up to 80%" | faster then the Intel 80387. Is that true of the 486 also? | (ie. is the 387 on-board of the 486 200% SLOWER than a clone) They are using the old 387-20 as the basis for that. The 20 and 25 has an old mask with slow microcode. The new 387-25's, all 387-33's, and the 486 all have the fast microcode. Cyrix is a hell of a lot faster in 387SX, and cheaper, and lower power, but I don't think you will see much difference in speed from the new 387's. Just be sure you have one of the new ones, and not one made three months ago. | 2) I have heard that I can take an AT card (16-bit) and plug it | into the EISA buss. True? If so, will it slow down the other | EISA cards? (Like plugging in a MDA into a 16-bit-VGA system) I have seen 800KB sustained SCSI disk transfer while running a modem on an 8 bit serial card. I think you you can believe that one. | 3) Are there any EISA VGA cards out there? (Like an EISA | version of the ProDesigner II, or others) If so, are they faster? I'm told there are, but they are not common yet, and I would rather have one I know is compatible. Actually, I would like inexpensive, too. | 4) Is there an EISA IDE hard disk controller? I have some | IDE drives and I want to use them in my new system. Yes? | Also, if I have to get a new drive, should I stick with SCSI-2 | or ESDI? (I heard that SCSI-s sucks) Someone makes one, Ultrastor, I think. While they are fast, cheap, and reliable controllers, the firmware has been a bit odd. Ultrastrange, actually. If you need the power there are several companies making the boards. | 5) How would I, say, add a tape backup? I realize that there are | 2 types, one that hooks up to a floppy drive controller and one | that comes with its own card. (#2 applies to the second). Will | the EISA floppy/hard controller allow for this? (I want 1.2MB and | 1.44MB as a base) does it have more connectors? If I get the | type with a card, will I be able to use it with my system? | (see #2) While you can go with a Wangtek or Archive for about $500 these days, I think you would be better off with SCSI for it. If you get a lot of disk you can add a DAT tape. Anyone who can afford enough disk to need one can probably afford it ;-) -- bill davidsen - davidsen@sixhub.uucp (uunet!crdgw1!sixhub!davidsen) sysop *IX BBS and Public Access UNIX moderator of comp.binaries.ibm.pc and 80386 mailing list "Stupidity, like virtue, is its own reward" -me
tackett@ipla01.hac.com (Walter Tackett) (03/28/91)
i am buying an ibm pc clone with a 33MHz 80486 processor. the dealer says that it sports an ISA (as opposed to an EISA) bus architecture. Is this guy full of sh*t or does it make a critical difference, or what? my understanding was that ISA is basically a 16-bit bus structure! RSVP FAST! Please include any references to published material which may be of use to me. Thank you in advance. -walter tackett@ipla01.hac.com sahtirn@ipla01.hac.com
mosbrook@beach.csulb.edu (Brent Mosbrook) (06/28/91)
I have been given the task of training some salesmen next week, and don't really want to re-invent the wheel. Is there any good article/FAQ that anyone is aware of that will help me out in explaining the benefits of EISA? I have seen some very good, concise files posted here about modems, and thought that something like that is just what I need. Thanks for any and all info you can provide! -- +--------------------------------------+ | Brent Mosbrook KC6MWK | | mosbrook@beach.csulb.edu | +--------------------------------------+
jgb@prism.gatech.EDU (James G. Baker) (06/28/91)
In article <1991Jun28.010434.24421@beach.csulb.edu> mosbrook@beach.csulb.edu (Brent Mosbrook) writes: > >I have been given the task of training some salesmen next week, and don't >really want to re-invent the wheel. Is there any good article/FAQ that anyone >is aware of that will help me out in explaining the benefits of EISA? I'm currently knee-deep in Micro Channel hardware development. But, I've read a lot about EISA. One of the better "overview" magazine articles was in PC Magazine (which I am losing respect for rapidly). Basically it said that the EISA designers who wanted to show Big Blue that not everyone would jump off into MCA came up with a 32-bit bus very similar to MCA. (The xerox machine was probably still warm.) :-) Both have: 32-bit address and data Signals unique to each slot to activate and setup cards Allow cards to take control of bus more than DMA did in AT An extensive "setup" and CMOS configuration. vs ISA: 16-bit data, 24-bit address pseudo 32-bit slots for 386 machines but every manufacturer has its own proprietary "32-bit" slot for memory, etc. BUT, EISA slots can use ISA cards! true EISA cards slip down into the slots via a key-notch in the card. The setup tells the motherboard which slots are 8-, 16-, and EISA. I haven't heard of any compatibility problems. I think everyone is still waiting to see if MCA really becomes a standard in IBM's line. Or if EISA will win because of the ten-zillion cards out there for ISA. A lot of companies make EISA computers - Compaq, Dell, ALR, and others. EISA adapters are slowly creeping out - such as "Bus master EISA disk controllers". But still a lot of $$$ for people that might like ISA just as well. Hope this helps... >I have been given the task of training some salesmen next week, and don't >really want to re-invent the wheel. Is there any good article/FAQ that anyone >is aware of that will help me out in explaining the benefits of EISA? I have >seen some very good, concise files posted here about modems, and thought that >something like that is just what I need. > > >Thanks for any and all info you can provide! > > >-- >+--------------------------------------+ >| Brent Mosbrook KC6MWK | >| mosbrook@beach.csulb.edu | >+--------------------------------------+ -- BAKER,JAMES G - Undergraduate Lab Instructor, School of Electrical Engineering ____ _ _ Georgia Institute of Technology, Atlanta Georgia, 30332 | | _ |_) uucp: ...!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!jgb (_|. |_). |_). Internet: jgb@prism.gatech.edu, jgb@ee, jgb@eecom, jgb@cc