🚀 go-pugleaf

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