jdm@hodge.UUCP (jdm) (07/18/89)
I heard this crazy thing that the 80386SX is completely pin compatable with the 80286 then therefore it should be possible to replace the 286 on any motherboard with a 386SX. Anybody else heard of this? Would there not be some BIOS problems if this were possible? -- "I'm an anthropologist, not a computer systems architect, damit!" jdm@hodge.cts.com [uunet zardoz]!hodge!jdm James D. Murray, Ethnounixologist Hodge Computer Research Corporation 1588 North Batavia Street Orange, California 92667 USA TEL: (714) 998-7750 Ask for James FAX: (714) 921-8038 Wait for the carrier
mark@intek01.UUCP (Mark McWiggins) (07/19/89)
jdm@hodge.UUCP (jdm) writes: > I heard this crazy thing that the 80386SX is completely > pin compatable with the 80286 then therefore it should > be possible to replace the 286 on any motherboard with > a 386SX. Anybody else heard of this? Would there not > be some BIOS problems if this were possible? As I understand it, the 386SX is not only not pin compatible, it has enough timing weirdnesses vs. the 286 that a 286-to-386SX upgrade is generally infeasible except for chipsets like C&T's NEAT, which are designed for it. Mark McWiggins Integration Technologies, Inc. (Intek) 1400 112th Ave. SE #202 Bellevue WA 98004 (206) 455-9935 uunet!intek01!mark
johnl@ima.ima.isc.com (John R. Levine) (07/19/89)
In article <20851@hodge.UUCP> jdm@hodge.UUCP (jdm) writes: > > I heard this crazy thing that the 80386SX is completely > pin compatable with the 80286 then therefore it should > be possible to replace the 286 on any motherboard with > a 386SX. ... Somebody has been feeding you a line. The 386sx and the 286 are not pin compatible by a long shot. When the 386sx first came out, lots of us expected to see little daughterboards with an sx and glue logic to replace a 286 chip, but they never caught on. -- John R. Levine, Segue Software, POB 349, Cambridge MA 02238, +1 617 492 3869 { bbn | spdcc | decvax | harvard | yale }!ima!johnl, Levine@YALE.something Massachusetts has 64 licensed drivers who are over 100 years old. -The Globe
jca@pnet01.cts.com (John C. Archambeau) (07/19/89)
Yes, I have heard this...and no, it's not true. There is, however, an
unsubstantiated rumor floating around that there will be some 386SX
daughterboards for standard 286 boxes soon. The only things that are
identical about the 286 and 386SX are the following:
1. Data bus size (16-bits)
2. The manufacturer that we all know and love dearly by the name of Intel.
Do not replace your 286 with a 386SX unless you want July 4th, 1990 to come
about a year early or you have a 286 box that you want to see get blown up.
It's not a pretty sight frying your motherboard with a non pin compatable CPU.
Fortunately, I haven't seen it.
For more information on this...real the March '89 Byte, the cover story is the
80286 vs. 80386SX. Well worth reading if you are not decided on whether or
not to get a 286 or 386SX box.
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*--------------------------------------------------------------------------*/las) (07/20/89)
In article <4182@ima.ima.isc.com> johnl@ima (John R. Levine) writes: >In article <20851@hodge.UUCP> jdm@hodge.UUCP (jdm) writes: >>[Heard that 80386SX is pin compatible with 80286] >Somebody has been feeding you a line. The 386sx and the 286 are not pin >compatible by a long shot. When the 386sx first came out, lots of us expected >to see little daughterboards with an sx and glue logic to replace a 286 chip, >but they never caught on. The latest PC Magazine reviews 14 80386SX-based computers. "Two [of them], the Everex Step 386is and the Twinhead Superset 490 use daughtercards on their 16-MHz 286 motherboards..." They also state that Everex offers the daughtercard to owners of Everex Step 286 computers (12 & 16-MHz) for $699.00. They also state that "Cumulus Corp. and AOX both offer generic 386SX daughtercards to upgrade 286 machines." Language used in the description of these products implies that Cumulus "anticipates" rather than actually has available for shipment, their 386SX daughtercard. Of course the article had to have been written as many as 4 or 5 months ago thanks to magazine lead times and may not reflect the current situation. I understand that AOX has withdrawn its daughtercard product due to some sort of technical difficulty, however I'm not the authoritative source for such information. regards, Larry -- Signed: Larry A. Shurr (cbema!las@att.ATT.COM or att!cbema!las) Clever signature, Wonderful wit, Outdo the others, Be a big hit! - Burma Shave (With apologies to the real thing. The above represents my views only.) (Please note my mailing address. Mail sent directly to cbnews doesn't make it.)
kleonard@gvlv2.GVL.Unisys.COM (Ken Leonard) (07/20/89)
In article <4182@ima.ima.isc.com> johnl@ima (John R. Levine) writes: * In article <20851@hodge.UUCP> jdm@hodge.UUCP (jdm) writes: * > I heard this crazy thing that the 80386SX is completely * > pin compatable with the 80286 then therefore it should * Somebody has been feeding you a line. The 386sx and the 286 are not pin * compatible by a long shot. When the 386sx first came out, lots of us expected * to see little daughterboards with an sx and glue logic to replace a 286 chip, * but they never caught on. But they may be catching on, now. At least a couple different versions _are_ currently available. See the last issue of "PC" magazine (maybe it was "Byte", I'm not quite sure). ----- regardz, Ken
wales@gidday.dec.com (07/22/89)
G'Day All, In Electronics Today International (ETI) August '89 edition there is a circuit for a daughterboard for 286 machines to upgrade to 386SX. It also uses two PAL's for which they give all programming information. Here in Australia we can get these done for around $15 each so the actual cost of the upgrade is only a bit more than the cost of the 386SX itself. Unfortunately ther is no PCB available for this upgrade (yet??) but a full circuit diagram is given and it would not be too hard (they say) to wire wrap it. Maybe this is the start of things to come. Some other magazines may publish details with PCB's etc or maybe commercial ready made products will appear. Who knows??? =============================================================================== | | Internet: wales@gidday.dec.com | | David Wales - Sydney Australia | DEC Easynet: gidday::wales | | | FIDOnet: 3:712/502 (Paragon BBS) | | "Only 38 years 'till retirement!" | UUCP: ...!decwrl!gidday!wales | | | | | Opinions expressed are mine and | Voice: (61) 02-868-3937 A/H | | mine only! | (61) 02-412-7334 B/H | | | | ===============================================================================