prove@batcomputer.tn.cornell.edu (Roger Ove) (11/28/89)
I have an old XT clone and I'm tempted by some of the cheap 386SX motherboards. It would be nice to be able to salvage some of the old stuff, particularly the drives (ST225's). Most of these boards have a couple of 8 bit slots, but I assume you can't just plug in an XT drive controller (for bus timing and port assignment reasons). Is there a way to do this? If anyone out there has tried such an upgrade and has any advice, please post. Also, ST225's seem to perform very well in mac II's. Is there a way to get this kind of performance out of them in an IBM system? thanks, Roger Ove, ove@ncsa.uiuc.edu
nadkarni@ashok.dec.com (11/28/89)
In article <9361@batcomputer.tn.cornell.edu>, prove@batcomputer.tn.cornell.edu (Roger Ove) writes... >I have an old XT clone and I'm tempted by some of the cheap 386SX >motherboards. It would be nice to be able to salvage some of the old >stuff, particularly the drives (ST225's). Most of these boards have a >couple of 8 bit slots, but I assume you can't just plug in an XT drive >controller (for bus timing and port assignment reasons). Is there a way Please post this information as I'm interested too. I'm told that on some 286 motherboards you can use an XT HD controller by telling setup that there is no hard disk. How about the floppy controller and I/O ports ? Thanks, /Ashok Nadkarni
plim@hpsgpa.HP.COM (Peter Lim) (11/29/89)
> I have an old XT clone and I'm tempted by some of the cheap 386SX > motherboards. It would be nice to be able to salvage some of the old > stuff, particularly the drives (ST225's). Most of these boards have a > couple of 8 bit slots, but I assume you can't just plug in an XT drive > controller (for bus timing and port assignment reasons). Is there a way > to do this? If anyone out there has tried such an upgrade and has any > I don't see why not, unless your drive controller is a real old vintage; i.e. made in the good old days before the arrival of AT and/or Turbo XT. In that case you might not be able to run the controller at a bus speed of 8 MHz which is pretty much a standard now. Of course most latest board should have the option to let you run the bus at 12MHz or higher, but you'll need newer controller cards to live with that. In general, if you plug your controller card into an 8MHz 0Wait AT and it works, you should have no problem. Of course you must make sure that the 386SX you intend to buy can run the bus at 8MHz (not the CPU speed); preferrably selectable. I have a 25MHz 386 which can change the bus speed from 8MHz to 12.5MHz (half CPU clock), I am know using a PERSTOR controller card on loan and the stupid thing can't hack 12.5MHz, so I am forced to run the bus at 8MHz, but it still work :-).. ...... wait till my ESDI drive comes and I'll be able to run at 12.5MHz again !
crmeyer@voodoo.ucsb.edu (11/29/89)
-Message-Text-Follows- In article <6400@shlump.nac.dec.com>, nadkarni@ashok.dec.com writes... >Please post this information as I'm interested too. I'm told that on some >286 motherboards you can use an XT HD controller by telling setup that there >is no hard disk. How about the floppy controller and I/O ports ? If memory serves, since the XT hard disk controller has its own ROMs, you configure the AT as having no hard disk. You cannot use XT serial cards in an AT and LPT2 on an XT card will conflict with an AT floppy disk controller. (if my memory is wrong...please correct:^)
jca@pnet01.cts.com (John C. Archambeau) (11/30/89)
nadkarni@ashok.dec.com writes: >In article <9361@batcomputer.tn.cornell.edu>, prove@batcomputer.tn.cornell.edu (Roger Ove) writes... >>I have an old XT clone and I'm tempted by some of the cheap 386SX >>motherboards. It would be nice to be able to salvage some of the old >>stuff, particularly the drives (ST225's). Most of these boards have a >>couple of 8 bit slots, but I assume you can't just plug in an XT drive >>controller (for bus timing and port assignment reasons). Is there a way > >Please post this information as I'm interested too. I'm told that on some >286 motherboards you can use an XT HD controller by telling setup that there >is no hard disk. How about the floppy controller and I/O ports ? I have yet to see a motherboard that you can't put an XT controller into. I did it for almost a year. The issue isn't the controller or the motherboard really, but whether or not the on-board BIOS in your XT controller will get along with your AT BIOS if the setup is configured to 'not installed.' I know Pheonix BIOS will allow it because that's what I had. I know that Seagate's XT controller will work since they support the XT controller in an AT configuration. Award BIOS I don't know about. AMI BIOS should work. A lot of 386 boards are based on AMI, why Phoenix is downgraded upon with respect to the 386(SX) is a mystery to me. It might be that the AMI BIOS is the only one that fully supports the NEAT chip set by Chips and Technology, but I am only guessing. The controller won't work as fast as a 16-bit AT controller though, and some software WILL not work in an AT unless it has the 16-bit controller, especially those programs that do DMA. The sense the 286 is there and expect to be able to use the assumed IRQ and DMA channels with an AT 16-bit controller. As for dealing with the floppy drive, the solution is simple, but it will cost you about $40. You pop in an 8-bit AT/XT controller card. You can't really use your cheapo $15 dual XT floppy drive controller, it doesn't know what to do with 80 track drives, but a cheapo dual XT controller can be made to work with a DS/DD 3.5" drive which is an 80 track drive. I attribute these differences to the fact that the floppy drive controller that works in both an AT and XT is designed to work with ANY floppy drive configuration that you throw at it. Whether it be a little 360K DS/DD 5.25" to a 1.44 Mb DS/HD 3.5" floppy drive. As for the I/O ports, the only time you have to worry is when you have a piece of software that does not go through the hard drive BIOS calls. With respect to MS/PC-DOS, an XT controller will work in an AT with no problems. Run Xenix, OS/2, etc. it will probably laugh at you. Norton, VOPT, etc. don't care since they do everything from BIOS calls. Anything that accesses that controller directly will care that there's not an AT controller sitting there, but otherwise, it will work. Of course, here's a nice little tidbit to save all of you perspective people who are upgrading to an AT or 386 some money. There is a controller out that that has proven itself to me to be 100% Western Digital compatable with an under $100 price tag. They are the WA3-16 and WA6-V. They are effectively cost effective 100% (or so close to 100% you'd swear it was a real Western Digital) compatable version of the WD1003-WA2 and WD1006V-MM2 respectively. And both controllers support up to 16 MHz AT bus speeds, so you can use them in an high speed machine. I've seen the WA3-16 for about $80 and the WA6-V for just under $100 in the Computer Shopper. I tested the WA3-16 on something that demands a Western Digital or something that's very close to one, Minix. If it isn't WD compatable, Minix will go off on some strange tangent when it comes to a task regarding hard disk I/O. It works with no problems. // John C. Archambeau /* **--------------------------------------------------------------------------* ** Flames : /dev/null (on my Minix partition) **--------------------------------------------------------------------------* ** ARPA : crash!pnet01!jca@nosc.mil ** INET : jca@pnet01.cts.com ** UUCP : {nosc ucsd hplabs!hd-sdd}!crash!pnet01!jca **--------------------------------------------------------------------------* ** Note : My opinions are exactly that...mine. Bill Gates couldn't buy ** my opinion...but he could rent it for a few nanoseconds. :) **--------------------------------------------------------------------------* */
emmo@moncam.co.uk (Dave Emmerson) (12/02/89)
In article <6400@shlump.nac.dec.com>, nadkarni@ashok.dec.com writes: > In article <9361@batcomputer.tn.cornell.edu>, prove@batcomputer.tn.cornell.edu (Roger Ove) writes... > >I have an old XT clone and I'm tempted by some of the cheap 386SX > >motherboards. It would be nice to be able to salvage some of the old > >stuff, particularly the drives (ST225's). Most of these boards have a > >couple of 8 bit slots, but I assume you can't just plug in an XT drive > >controller (for bus timing and port assignment reasons). Is there a way > > Please post this information as I'm interested too. I'm told that on some > 286 motherboards you can use an XT HD controller by telling setup that there > is no hard disk. How about the floppy controller and I/O ports ? > My 286 AMI NEAT combination does just that. You set the appropriate bus waitstates for the selected bus clock (in CMOS non-volatile memory), and -with my old ST11 controller- set the hard drive to type 15 (0 Mb), NOT non-existent. No problem, nice easy bit-by-bit upgrade path, go for it! - NB this is a ROM boot-up routine, there's no Catch-22 with having to have a drive working to load a program to configure the drives. Dave E.