Michael Devore escreveu:
>> So now I have something to wish for. It looks that the most compatible
>> _and_ safe behaviour is to map RAM to X=TEST, which was exactly your
>> first suggestion :)
> Safest, but very incompatible with MS expected RAM behavior. Not the
> reverse either, just something quite different. I don't expect users
> would want RAM == X=TEST.
Ok. If you say so, I agree. And even more because of what is below ;-)
>> nothing - No UMB available, smaller lower memory, only for problematic
> Nothing is the same as RAM with FreeDOS EMM386. UMB's are available and
> auto-scanned for ROM signatures in range C000-EFFF. EMS is present, I
> forget the formula for how much but could look it up. Probably defaults
> to 32M, or successively halving that until sufficient memory exists.
I like this. Does MSDOS have UMB in this case? I allways understood that
In any case,
>> NOEMS - I don't use EMS and UMB is enabled. Basic use, could be UMBPCI
>> but this is hardware dependent. VCPI is only needed because it of
>> EMM386 itself.
> NOEMS leaves support for a few EMS calls on with MS-DOS, which is
> stupid, but could be for easier VCPI support. FreeDOS EMM386 also
> supports these EMS calls under NOEMS because several programs have come
> to depend on this MS-DOS stupidity. Then there's the EMM device driver
> renaming, but don't get me started... VCPI pool allocation is made with
> NOEMS up to 12M automatically, based on 1/4th of available memory. I
> think. Documented in EMM386C.C and EMM386.ASM source.
Just to put the point over the "i"s (just a badly translated saying):
In this case UMB is available? I understand that the answer is yes, but
it is not clearly stated in the above paragraph.
Even it the implementation is stupid, IMHO the inportant fact of this
option is liberating 64k on UMB :)
>> RAM - EMS and UMB available
> Default option with FreeDOS, no difference if it's there or not.
>> NOEMS RAM - Maybe here the RAM option should not be used (not needed),
> Same as NOEMS, above.
One more question: How do I turn off UMB?
This is what I understood so far (please correct me if in error)
With both UMB and EMS: nothing (this needed RAM in MSDOS)
With UMB but not EMS: NOEMS
No UMB but with EMS: ??? (this was nothing in MSDOS)
Neither UMB nor EMS: don't load EMM386
There is still a "???" :(
May I suggest a table similar to this in the docs or even help?
thanks for everything so far,