Mail Archives: opendos/2000/12/01/12:53:11
On Fri, 01 Dec 2000 Patrick Moran wrote:
> Why do you need those buffers? There are caching programs
> available for CD.
I have just been asked in private conversation, which CD caches
are avialable. I'm probably not up to date, as I have only tested
CD-Quick so far. Can you recommend any?
> If those things actually spun at 24X or 36X they would probably
> fly right out of the drive!
In the April issue of the c't magazine there was an article where
they reported about CDs that broke in 36x and 40x drives due to
the high centrifugal forces. I'm still not completely sure if this
was meant seriously or as an 1st April joke... ;-) But anyway,
from the noise the produce I can image almost anything happen... ;->
> What environment are you talking about then? The 7K?
No, the 112 byte environment. The 7 Kb is the size of the
resident driver when it uses DPMS.
> According to the LIM 4.0 specifications, those 4 16K blocks DO NOT have to
> be contiguous. They can reside in different areas, but I have yet to see an
> EMM386 do that. Also you are not restricted to just 64K frame, you can use
> as many 16K chunks as you want. It is possible to have as large as a 256K
> frame located in conventional memory.
EMS 3.xx works through a 64 Kb EMS frame page with 4x16 Kb windows in
there, but under EMS 4.00 you can map in EMS outside of the frame,
even below the A000h address (this is called memory backfilling).
This technique derived from EEMS, that's true.
Even the AST machine must at least have 128 Kb or 256 Kb of
conventional memory, otherwise DOS cannot boot (DR-DOS 7.03 needs
128 Kb to boot). The remainder of the memory can be backfilled
using EEMS or EMS 4. I think, Windows 3.xx is almost the only
application to make use of that. As far as I know the MS-DOS
EMM386 also supports this, while the DR-DOS EMM386 does not
(at least it lacks these command line options). I'm not
sure if EMS 4 still requires a FRAME page or if this is optional
(for backward compatibility). Anyone?
Matthias
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Matthias Paul, Ubierstrasse 28, D-50321 Bruehl, Germany
eMail: <Matthias DOT Paul AT post DOT rwth-aachen DOT de> or <mpaul AT drdos DOT org>
Web : http://www.rhrz.uni-bonn.de/~uzs180/mpdokeng.html
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