Path: utzoo!attcan!uunet!bnrgate!bnr-fos!bigsur!bnr-rsc!bcarh185!schow From: schow@bcarh185.bnr.ca (Stanley T.H. Chow) Newsgroups: comp.sys.amiga Subject: Re: Return of the processor wars, part II Message-ID: <1652@bnr-rsc.UUCP> Date: 13 Jan 90 21:50:50 GMT References: <1646@bnr-rsc.UUCP> <90010.202827YTHPRGDB@MTUS5.BITNET> Sender: news@bnr-rsc.UUCP Reply-To: bcarh185!schow@bnr-rsc.UUCP (Stanley T.H. Chow) Followup-To: comp.sys.ibm.pc Organization: BNR Ottawa, Canada Lines: 48 Summary: Keywords: In article <90010.202827YTHPRGDB@MTUS5.BITNET> YTHPRGDB@MTUS5.BITNET writes: >In article <1646@bnr-rsc.UUCP>, schow@bcarh185.bnr.ca (Stanley T.H. Chow) says: >[...] >> f) The Intel x86 family is object code compatible. >> > >Question: Are the 286 & 386 object-code compatible in their >respective "protected" modes? I got the impression that this >only applied to the "real 8086" and "virtual 8086" modes. As far as I know, the 386 protected mode is a superset of the 286 protected mode. (But then, I only read the 386 book for the first time yesterday). > >Many of the neat added abilities of the 286 and >386 (including addressing beyond 1M of memory) are only available >in the "protected" modes of operation. IMHO, Intel's mode-based >emulation adds just as much complexity as (if not more than) the >problems with MOV SR in the 68K family. > You know, this is the second follow-up that actually has facts instead of How-dare-you-slander-Amiga/Motorola. Quite possible. Since I have done no programming on x86 machine (okay, I actually did write one little C program), I don't know. The question is: whose problem is it? The OS writer? The application writer? Or the User? It seems to me the mode switch stuff is mostly in the OS and some in the application, so as a user, I am happy. As a programmer, I would probably grummble, but since I can keep the user happy, I as the programmer would probably be happy too. >Granted, Intel did a very nice thing in giving us the "virtual 8086" >mode to allow multiple 8086-based programs (DOS-based?) to execute >concurrently. This seems to be an excellent idea, but why then >does OS/2 only allow one DOS task (in the compatibility box)? I assume this is a limitation of OS/2 that is designed to force users to migrate to "true" OS/2 applications. Since this is getting away from Amiga, I have redirected the follow-up to comp.sys.ibm.pc. Stanley Chow BitNet: schow@BNR.CA BNR UUCP: ..!psuvax1!BNR.CA.bitnet!schow (613) 763-2831 ..!utgpu!bnr-vpa!bnr-rsc!schow%bcarh185 Me? Represent other people? Don't make them laugh so hard.