How to shrink data?

Thread View: alt.msdos.programmer

4 messages

[T] Back to Threads [V] Tree View [G] Group Articles

4 total messages Started by Kent Iler Tue, 28 Jul 1992 04:59

#106

Author: Kent Iler
Date: Tue, 28 Jul 1992 04:59

9 lines
887 bytes

Hello,
   I am trying to write an envelope printing program which contains
a database of all the people you want to print.  Also, I have a database with
all the zipcodes and citys, so they can enter Either one and the city come up.
I'm not too concerned with archiving/compressing the information about the
people, but I NEED to do something about the zip codes and citys.  It's
a 600 k file with each zipcode on a seperate line.  Any help would be
greatly appreciated.  Thanks.
																		--Kent

How do I get a the memory above 1M ?

#108

Author: Kenneth Cameron
Date: Tue, 28 Jul 1992 14:07

30 lines
1765 bytes

Whats the cleanest way to get at the memory above the 1Meg mark,given the
following conditions ?

The application has to run under MS-DOS, on a 486dx. In other words it
has to be in real mode most of the time.
I'd like to be able to get at it from within an iterrupt routine
running at 8KHz. (Although not essential, access from within the main
program would do).
I'm working with Borland C++ 3.1.
I don't want to use a DOS extender like Phar Laps.

I had thought of writing a peek and poke function using 32bit registers but
that generates an int 13h on accesses outwith the megabyte range.
At the moment I'm considering changing the memory management set up to map
the extra into the bottom megabyte block at a time (although more than
the 64k that expanded memory provides). This looks like it requires a
change of mode and back.

This is for some control software I'm writting that has to drive 125 analogue
channels at 16Hz and sample 512 channels at 16Hz. All with a single ADC and
DAC. As well as record the samples to disk and maitain a WIMP interface.
(I need to buffer the drive channels in memory, because reading and writing
at these rates is very hard. But there can be megabytes of the stuff).

Any suggestions ? Anyone ?

,Kenneth Cameron.

--
Kenneth@Edinburgh

Re: How do I get a the memory above 1M ?

#111

Author: Joe Huffman
Date: Wed, 29 Jul 1992 04:34

23 lines
1165 bytes

kc@dcs.ed.ac.uk (Kenneth Cameron) writes:

>Whats the cleanest way to get at the memory above the 1Meg mark,given the
>following conditions ?

DOS extenders are definitely the cleanest way to do this.

>The application has to run under MS-DOS, on a 486dx. In other words it
>has to be in real mode most of the time.

MS-DOS, on a 486dx, does not mean real mode is required 'most of the time'.

>I'm working with Borland C++ 3.1.
>I don't want to use a DOS extender like Phar Laps.

Could you elaborate?  Pharlap and Rational Systems both make a very nice
'286 extender.  They make accessing extended memory so easy that I don't
think I can give them enough praise.  The only drawback that I know of is
the price...

-- 
netcom!proto!joe
joe@proto.com

Re: How do I get a the memory above 1M ?

#119

Author: Redmond English
Date: Fri, 31 Jul 1992 13:05

38 lines
1986 bytes

In article <1992Jul29.043416.10449@proto.com> joe@proto.com (Joe Huffman) writes:
>kc@dcs.ed.ac.uk (Kenneth Cameron) writes:
>
>>Whats the cleanest way to get at the memory above the 1Meg mark,given the
>>following conditions ?
>
>DOS extenders are definitely the cleanest way to do this.
>
>>The application has to run under MS-DOS, on a 486dx. In other words it
>>has to be in real mode most of the time.
>
>MS-DOS, on a 486dx, does not mean real mode is required 'most of the time'.
>
>>I'm working with Borland C++ 3.1.
>>I don't want to use a DOS extender like Phar Laps.
>
>Could you elaborate?  Pharlap and Rational Systems both make a very nice
>'286 extender.  They make accessing extended memory so easy that I don't
>think I can give them enough praise.  The only drawback that I know of is
>the price...
>
>-- 
>netcom!proto!joe
>joe@proto.com

If the PharLap DOS extender is too expensive, consider changing to Zortech
C++ - the whole compiler is cheaper than the PharLap DOS extender.

The Zortech compiler comes with an extender, but for $69 you can get a truly
excellent extender from Flashtek, which can even support virtual memory.

I *highly* recommend the Flashtek extender - if you have Zortech C++ *get
this extender* !!  (By the way, I am not affiliated with Flashtek, I'm
merely an impressed customer).

                               Red/.

Thread Navigation

This is a paginated view of messages in the thread with full content displayed inline.

Messages are displayed in chronological order, with the original post highlighted in green.

Use pagination controls to navigate through all messages in large threads.

Back to All Threads