🚀 go-pugleaf

Mike Copeland wrote:

>    First, Turbo Pascal 7.0 has access only to Real Memory - the 640K
> in which programs execute.  You can allocate and use several pages of
> 64KB of Heap data, using pointers, and the total amount of Heap is
> dependent on several factors:
>   1. Whether or not you're executing your program in the TP IDE (not a
> good way to do it if you're using pointers or making Exec calls);
>   2. How much Real Memory is being allocated to the DOS process you're
> running.  I don't know how NT does it, but you need to maximize this
> value...and you should be working with 600K+ to have maximum resources
> available;
>   3. The value MemAvail returns when you call it as your program executes
> (affected by whatever's running when you execute your program);
>   4. The treatment of pointers which have been used and aren't needed any
> more - are you releasing them?
>    All told, you should be able to use at least 400K of Heap memory (in
> 64KB chunks), providing you deal correctly with the above issues.
>    You can also use Overlays, to make your program smaller and make even
> more Heap memory available...depending on the application, of course.
>    Most of all, _don't_ run your program in the IDE, because it consumes
> an enormous amount of Real Memory while it's in execution - it doesn't
> swap out when your compiled program executes.  Compile to Disk and
> execute it as a DOS application.

  The easiest way to get around these limitations would be to use a
32-bit compiler such as p32 or tmt-pascal, however if you don't want to
(or can't) use these, then you could try using EMS. EMS is one way that
has been developed to utilise the memory above the 1 meg limit. 

  I'm not sure if tp7 can handle pointers to EMS memory or anything
(i've never used it myself), but Telemachos of Peroxide has produced a
tutorial on how to use EMS (it is aimed towards graphic programs, but i
guess the principle is the same). It's called PXDTUT2.ZIP, you sould
find it if you search altavista or whatever.

  Hope this helps ...

	- Bob