ID:AB Intel AboveBoard Plus
Quarterdeck Technical Note #150
by Stan Young

Q:   How do I set up my Intel AboveBoard Plus to best support
     DESQview or for use with QRAM?

The Intel AboveBoard Plus supports in hardware many of the features
of the EMS 4.0 software specification that DESQview and QRAM would
like to use.  It is capable of mapping EMS memory below the 640K
barrier to support DESQview's multitasking.  It also can map EMS
memory into high memory addresses above 640K and below 1 Megabyte,
a feature which is useful to both DESQview and QRAM in order to get
more DOS memory.  Obtaining these features, however requires that
the board be set up in specific ways, and there are some
restrictions in the way the board and driver work that are
important to understand.

1.  Backfilling Motherboard Memory:

Backfilling motherboard memory is NOT important to the operation of
QRAM.  But, as in the examples given in Appendix B of the DESQview
manual, for Enhanced Expanded Memory Boards if you want to have
large expanded memory partitions in which you can multitask
programs, it is necessary to disable motherboard memory and have
the AboveBoard Plus fill memory out to 640K.  The lowest the
AboveBoard Plus will place EMS4 pages is from 256K, so it is not to
your advantage to backfill any lower than that, even if your
machine will support backfilling from a lower address.  If your
machine will allow the board to fill out from 256K, you will be
able to get expanded memory partitions of 384K. Unlike the examples
in the manual shown for EEMS cards, the partitions will be 384K
regardless of the type of video card you have, as the Intel
hardware will not allow for any EMS expanded memory pages to be
mapped into the video areas. Once the board is backfilling
motherboard memory addresses, one very important configuration item
remains relative to the driver. You must specify the "MC" (Map
Conventional) parameter to the EMM.SYS driver. Reference to this
parameter is somewhat buried in the Intel manual, but this
parameter must be specified in order to have the driver set
expanded memory pages in the 256K-640K range.

2.  Set the "Page Frame" as low as possible:

This is important for BOTH DESQview and QRAM users.  The AboveBoard
Plus driver will only map memory above 640K as one contiguous
block, starting with the original 64K EMS page frame.  For any
other memory to be mapped, it must be directly above and contiguous
with the page frame.  This might be changed in a future release of
the driver, as other EMS 4.0 drivers are not so restrictive as to
where the additional memory resides.

Because of this requirement, and because some versions of the Intel
installation program default the page frame to a "D000" address, 
memory addresses that might be mapped are often bypassed.  To get
best use from the memory, set the page frame as low as possible.


The AboveBoard driver which became available when Intel started
shipping QRAM with its boards defaults the frame to the lowest
possible address. Upgrade drivers are available from Intel directly
and are posted on Intel's electronic bulletin board.

If you do not have such a driver, we have determined that the
easiest way to be sure the frame is low is to change the CONFIG.SYS
file so the the frame assignment (usually D000) is set to C000. 
While it is often the case that a C000 page frame setting might be
in conflict with video ROMS or other installed devices, it is our
observation that the Intel driver generally detects these devices
and on boot will determine that the setting is inappropriate and
will select instead the lowest frame setting that is free -- just
what we wanted.  This method, while easy, may not be foolproof, so
if you encounter difficulty with the frame the Intel driver
selects, you will have to do some digging into your hardware
documentation to see what area might be available.

3.  Install the QEXT.SYS driver:

Assuming you have an AT, you can configure some of the Intel
AboveBoard Plus memory as exTENDed memory.  By loading the QEXT.SYS
driver in your CONFIG.SYS file (see page 148 in the DESQview
manual), this driver allows you to take 60K of extended memory and
make it available for running some of DESQview's code, thus
lowering the overhead of DESQview in DOS and increasing your
Maximum Available Conventional Memory by 60K as shown by the Memory
Status program.

Early versions of the AboveBoard Plus only allow you to configure
extended memory in increments of 512K, so on these systems, you
have to reserve 512K of extended memory to support the 64K QEXT
driver.  The remaining memory might be used as a VDISK, or by a
disk cache, but will not be available as expanded memory. Intel has
recently begun shipping boards which can allocate memory in 128K
segments, and an upgrade for existing boards is available.

If you have other extended memory on the machine, you may not want
to allocate any of the AboveBoard as extended memory. You would
simply install the QEXT.SYS driver and as long as the extended
memory starts at 1 megabyte (1024K), QEXT will use it.

As is usual, when using an expanded memory system, you will want to
load DESQview using the XDV.COM loader as indicated on page 139 of
the DESQview manual. The settings above should allow you to get the
best memory sizes for DESQview.  Your Memory Status program will
probably show figures somewhat less than listed in the DESQview
manual.  This is because the AboveBoard Plus will not map into the
video memory area, but the memory obtained in the windows should be
adequate for most purposes.
Intel Tech Support:     800-538-3373
Intel BBS:              503-645-6275
Intel Support FAX back: 503-629-7576

        Copyright (C) 1991 by Quarterdeck Office Systems
             * * *   E N D   O F   F I L E    * * *