ndeng@EULER.BERKELEY.EDU (10/24/89)
There currently several packages can utilize the V86 mode of 386. (MS/Windows, DESQView, etc.) However, I found none of them can give a user a full 640KB (or at least 600KB) in the virtual 86 mode. Is there any environment which may give a full 640K for DOS applications? or this is an impossible thing? (I am not familiar with 386MAX or VMOS) Does anyone have any experience on it? ndeng@euler.berkeley.edu
zech@leadsv.UUCP (Bill Zech) (10/24/89)
In article <8910231849.AA21907@euler.Berkeley.EDU>, ndeng@EULER.BERKELEY.EDU writes: > > There currently several packages can utilize the V86 mode of 386. > (MS/Windows, DESQView, etc.) However, I found none of them can give > a user a full 640KB (or at least 600KB) in the virtual 86 mode. > > Is there any environment which may give a full 640K for DOS applications? > or this is an impossible thing? (I am not familiar with 386MAX or VMOS) > Does anyone have any experience on it? > Look into OS/386 from A.I. Architects. They do tricks to map DOS out of the way, even the video if you want. Your DOS programs can use up to 1 Meg of RAM. There are trade-offs, however. If you map all that stuff out, the system has to context-switch to make them available. OS/386 provides its own extensions for various functions that you can call directly instead of using the DOS interrupts, and they can improve your speed of execution. It's an interesting package, well worth looking in to. It will also support protected mode programs compiled with Microsoft C and MetaWare High C. -Bill
davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr) (10/24/89)
In article <8910231849.AA21907@euler.Berkeley.EDU>, ndeng@EULER.BERKELEY.EDU writes: | Is there any environment which may give a full 640K for DOS applications? | or this is an impossible thing? (I am not familiar with 386MAX or VMOS) | Does anyone have any experience on it? The best you will get is what you would have with DOS and no TSRs. The 386 can't make DOS vanish, it has to be present to run. -- bill davidsen (davidsen@crdos1.crd.GE.COM -or- uunet!crdgw1!crdos1!davidsen) "The world is filled with fools. They blindly follow their so-called 'reason' in the face of the church and common sense. Any fool can see that the world is flat!" - anon
madd@world.std.com (jim frost) (10/24/89)
In article <8910231849.AA21907@euler.Berkeley.EDU> ndeng@EULER.BERKELEY.EDU writes: | |There currently several packages can utilize the V86 mode of 386. [...] |Is there any environment which may give a full 640K for DOS applications? Yes. The DOS-under-UNIX utilities such as VP/ix do this nicely. I believe all major 386 versions of UNIX supply this standard or as an option. This may not be useful to you, but the ability to have more V86 boxes running than you have available memory is sometimes considered a feature. jim frost software tool & die madd@std.com
sechzer@zodiac.rutgers.edu (S. L. Sechzer, Economics, Rutgers U) (10/25/89)
In article <8910231849.AA21907@euler.Berkeley.EDU>, ndeng@EULER.BERKELEY.EDU writes: > > There currently several packages can utilize the V86 mode of 386. > (MS/Windows, DESQView, etc.) However, I found none of them can give > a user a full 640KB (or at least 600KB) in the virtual 86 mode. > > Is there any environment which may give a full 640K for DOS applications? > or this is an impossible thing? (I am not familiar with 386MAX or VMOS) > Does anyone have any experience on it? > > ndeng@euler.berkeley.edu VM/386 for IGC lets you configure even more than 640 K in the current version. Selig L. Sechzer
davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr) (10/25/89)
In article <1989Oct24.164101.21281@world.std.com>, madd@world.std.com (jim frost) writes: | In article <8910231849.AA21907@euler.Berkeley.EDU> ndeng@EULER.BERKELEY.EDU writes: | |Is there any environment which may give a full 640K for DOS | applications? | | Yes. The DOS-under-UNIX utilities such as VP/ix do this nicely. Actually this only make 640k available for a virtual machine. By the time you load DOS, COMMAND.COM and the redirector you get (looks on another virtual machine) 578208 bytes free for the application itself. I believe that with Desqview and QEMM I got something like 602000, give or take a bit. I'm told that there is a product which moves most of DOS out of the address space and leaves 635k for the application (which was the original question). I'm also told that if the app does a lot of DOS calls the context switching kills the performance. I haven't tried it. I interpreted the question to refer to the memory available for the application. If you want a lot of memory for the app get a non-PC compatible which runs MS-DOS, such as the Tandy 2000, and you can have about 800k for the apps. -- bill davidsen (davidsen@crdos1.crd.GE.COM -or- uunet!crdgw1!crdos1!davidsen) "The world is filled with fools. They blindly follow their so-called 'reason' in the face of the church and common sense. Any fool can see that the world is flat!" - anon
john@jwt.UUCP (John Temples) (10/26/89)
In article <1457@crdos1.crd.ge.COM> davidsen@crdos1.UUCP (bill davidsen) writes: >| In article <8910231849.AA21907@euler.Berkeley.EDU> ndeng@EULER.BERKELEY.EDU writes: >| |Is there any environment which may give a full 640K for DOS >| applications? >| >I believe that with Desqview and QEMM I got something like 602000, give >or take a bit. On a monochrome 386 system, QEMM (WITHOUT DESQview) gives you 704K user memory. On a CGA system, QEMM gives you 736K. You can also load your device drivers and TSRs in high memory, above video memory. On my 386 monochrome system with QEMM, CHKDSK under COMMAND.COM shows 664784 bytes of memory available out of 720896. That leaves MORE than 640K available user memory. Unfortunately, QEMM doesn't provide that extra memory if you've got a VGA or EGA based system. >If you want a lot of memory for the app get a non-PC >compatible which runs MS-DOS, such as the Tandy 2000, and you can have >about 800k for the apps. A less-incompatible solution would be to get a 286 based system with an ALL Chargecard. I believe you can get about 800K user memory by letting the Chargecard relocate the video memory. And you can turn off the Chargecard any time, leaving you with a hardware-compatible system, unlike the Tandy 2000. -- John Temples -- UUCP: uunet!jwt!john
wek@point.UUCP (Bill Kuykendall) (10/27/89)
>There currently several packages can utilize the V86 mode of 386. >(MS/Windows, DESQView, etc.) However, I found none of them can give >a user a full 640KB (or at least 600KB) in the virtual 86 mode. I doubt you're getting more than 600k now. 'DOS loads into the 640k space leaving about 591,000 bytes free on most of my systems running Compaq DOS 3.31. With Desqview & QEMM, the worst case (with EGA or VGA) winds up costing about 10k extra (assuming that you have extended memory that Desqview can use). The best case (with Hercules or CGA) can net you an *increase* in available program space (over 700k!). This is possible because QEMM will append unused video RAM area to the 640k, yielding as much as 736k for 'DOS. Desqview will use high memory (between top-of-video and bios addresses) and LIM 4.0 (created by QEMM from extended memory above 1MB) to store all but 10k of it's code.
wek@point.UUCP (Bill Kuykendall) (10/28/89)
>A less-incompatible solution would be to get a 286 based system with an >ALL Chargecard. I believe you can get about 800K user memory by >letting the Chargecard relocate the video memory. And you can turn off On the other hand, the chargecard costs almost as much as a 386SX motherboard and it's harder to install...
brown@vidiot.UUCP (Vidiot) (11/01/89)
In article <[2717.2]comp.ibmpc;1@point.UUCP> wek@point.UUCP (Bill Kuykendall) writes:
<>There currently several packages can utilize the V86 mode of 386.
<>(MS/Windows, DESQView, etc.) However, I found none of them can give
<>a user a full 640KB (or at least 600KB) in the virtual 86 mode.
<
<I doubt you're getting more than 600k now. 'DOS loads into the 640k space
<leaving about 591,000 bytes free on most of my systems running Compaq DOS
<3.31. With Desqview & QEMM, the worst case (with EGA or VGA) winds up
<costing about 10k extra (assuming that you have extended memory that
<Desqview can use). The best case (with Hercules or CGA) can net you an
<*increase* in available program space (over 700k!). This is possible
<because QEMM will append unused video RAM area to the 640k, yielding as much
<as 736k for 'DOS. Desqview will use high memory (between top-of-video and
<bios addresses) and LIM 4.0 (created by QEMM from extended memory above 1MB)
<to store all but 10k of it's code.
I think the original poster is asking if a software company will give the
full 640K that DOS thinks it has in non-V86 mode. Obviously you lose part of
that 640K when DOS is loaded. But, DesqView does eat up part of each of the
virtual partitions.
I suggest getting a copy of IGC VM/386. Each virtual parition is exactly like
a bunch of mini PCs. Each partition can run a different version of DOS. Before
I put Unix on this PC of mine, I used VM/386 all the time. If a partition is
inactive, you can put it to sleep, therby providing those time slices to the
other active paritions. Excellent software.
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