VMS40
=====

This is a device driver that makes either a hard disk or a floppy disk
into LIM4 expanded memory. It is a software emulation of the 28
function standard set forth in the Lotus/Intel/Microsoft Expanded
Memory Standard (LIM/EMS) version 4.0. All of the EMS 4.0 functions
that can be implemented through software are provided by VMS40, with
the exception of the DMA functions included in the Alternate Map
Register Set function (function 28).

The program is backwards compatible with software written for the
earlier LIM 3.2 standard (courtesy of Lotus, Intel & Microsoft). It
lets you specify which drive to use for expanded memory, and how much
disk to reserve.

The trial version VMS40.240 restricts you to reserving no more than
240K for LIM memory, while the registered version VMS40.SYS allows you
to reserve up to 32M

You install VMS40 as you would any other DOS device driver through you
CONFIG.SYS file. When you include the driver in you file, be sure to
include the drive and path information so that DOS can find the file
at boot time. The full syntax is

  DEVICE=[d:\][path\]VMS40.SYS [d:] [nnn] [/Fm]

where [d:\][path\] specifies the drive and path in which the driver
lives.

The optional [d:] specifies which drive to place the Virtual LIM
memory on. If omitted, it defaults to C: if you boot from a hard disk,
and A: if you boot from a floppy.

The optional [nnn] specifies the amount of memory you wish to reserve,
in Ks (Kilobytes). If omitted, the trial version uses a default (and
maximum) value of 240K, while the registered version uses a default
value of 360K.

If you have high memory available, you can set the page frame to a
high memory address by using the /F parameter:

        /F1     = C000 - CFFF
        /F2     = C800 - D7FF
        /F3     = D000 - DFFF
        /F4     = D800 - E7FF
        /F5     = E000 - EFFF
        /F6     = E800 - F7FF
        /F7     = A000 - AFFF

If you use this parameter, it must be LAST. Please run the program EMS
to test that everything works on your machine. IF YOU DO NOT HAVE HIGH
MEMORY, but you try to locate the page buffer there, you will not get
an error, BUT the data stored to LIM memory will be trashed!


Example
=======

   DEVICE=C:\UTILS\VMS40.SYS 6000

which uses the registered version residing in directory UTILS on drive
C: to reserve 6000K (= 6M) on drive C: for expanded memory.

As with all device drivers, once installed, it can only be removed by
rebooting.

The VMS40 driver logically maps disk-memory pages of 16k blocks
into four contiguous physical pages of conventional RAM. Including the
64K physical page map area, the installed size of the driver is
approximately 69K. VMS40 cannot map the pages into any other area than
the 64K window it allocates automatically on boot up.

The program allocates a disk file called $VMS40@@.VM$ in the root
directory. Its attributes are System and Hidden. It is allocated at
the appropriate size to hold the LIM memory pages. Don't try deleting
it if you have the driver running!!! If you allocate the file on
floppy, don't remove the floppy while the driver is running!!!

Naturally, using disk to simulate LIM memory is somewhat slower than
having the appropriate hardware implementation, but it is also a lot
cheaper! If you need to run big spreadsheets, or use Borland's
standalone debugger to debug a really large program, and you cannot
afford 2Meg of LIM memory, then VMS40 is your answer.

LMS40
=====

This is for use on AT computers wih extended memory above the 1 Meg
barrier. This driver converts extended memory into LIM memory, in a
similar fashion to VMS40.

Example
=======

   DEVICE=C:\UTILS\LMS40.SYS 1400 /F5

which converts 1.4M of extended memory into LIM 4 expanded memory,
with a page frame at E000


HI MEMORY LOADS
===============

If you have a machine that has free memory above 640K and below 1M,
AND you have a suitable loader such as Quarterdecks QEMM, you can free
up the 69k below and load the entire device driver into Hi Memory.
Consult your software manual for details on how to load device drivers
into Hi Memory. In this situation, DO NOT use the /F parameter, but
let the page frame default to follow after the driver. (otherwise you
may confuse the hi load program)


FILES ON THIS DISK
==================


VMS40.SYS               disk LIM device driver
VMS40.DOC               this document
LMS40.SYS               extended Memory LIM emulator
VMS40.TXT               specification of LIM 4 function calls

EMS.PAS                 public domain program that tests LIM memory
EMS.EXE                 compiled version of above


If you have any constructive comments, or would like to know more
about our products, please contact us.


KNOWN PROBLEMS
==============

VMS40 - Desqview appears to trash the page frame. When this is
        fixed, you will all receive a replacement version.

LMS40 - NONE - this works with 4Dos & Desqview