Re: Re: UMB and 386/486 --> status of FreeDOS emm386 etc.

> > I have nothing against FreeDOS EMM386. I have against Micro$ofts's.
> > What is the completion state of FreeDOS EMM386? Is it stable? What
> > services are running? Does it provide UMB?
> 
> FreeDOS emm386 is stable IF you use it with the himem that comes with
> it. After fixing all known incompatibilities, there are still some
> unknown incompatibilities with FDXMS left :-(.
> You cannot use it with > 64 MB RAM, as the page tables will point to
> the void for the RAM beyond that pointer, even for things loaded
> -before- emm386. That is, using FDXXMS with FreeDOS emm386 is futile
> as a way to get > 64 MB of sum(EMS, XMS).
> 
> FreeDOS emm386 supports UMBs and EMS. Its big downside is that it does
> not support VCPI. For that reason, you cannot run any protected mode
> programs (like programs that use DPMI, for example djgpp compiled
> programs) after loading FreeDOS emm386.

Please explain something to me: If I run some protected mode programs
with _only_ fdxms (which dos not provide VCPI) they run. Why is it 
that such program will stop working?

> I personally prefer using UMBPCI for getting UMBs

this is HW based. I use it on all PCIs so far without problems :)

> (alternative choices
> are HIRAM, URAM, RDOSUMB),

HIRAM is HW based too. Are the others too? where can I get them?

> but this means that I have no EMS (I normally
> do not need EMS). You can find a list of supported hardware for UMBPCI
> and the like in the technotes (#177 I think). If your hardware is
> supported, you have UMBs in a very efficient way. If not, you must use
> any variant of emm386 to get UMBs. An example of non-supported hardware
> are AMD KT133 motherboards for Athlon, as far as I remember. Alas, cool
> processor and not too expxensive!

Yes, I want a non-hw version for old machines and for future incompatibilities.
I believe that UMBPCI will stop working some day :(

> For having UMB -AND- EMS, I use DR DOS emm386. This also has a built-in
> DPMI host for protected mode software, but it also offers the normal
> VCPI support. If you have it with DPMI=ON in your config.sys, some low
> level drivers may break. But in normal EMS/UMB only mode, it is very
> neat. You must use VERSION=4.01 in config.sys or my personal patched
> version or have a kernel that offers > 64k RAM to device drivers to use
> it (I HOPE that 2027 will), because it uses lots of RAM for a short
> moment during installation (but then frees most of it, moving itself
> beyond the 1 MB boundary).
> PS: Some versions of MS emm386 work as well, some others do not. The
> configuration is a bit tricky. But you did not want to use it anyway :-).

I am seeking a 100% percent free instalation, so DR or MS's are no good :(

Alain