Jason Aller Floppy Collection/101.img/QW10INST.ZIP/QWHITE10.EXE/AB_PLUS.TEC

Text File | 1990-07-16 | 5.9 KB | 120 lines

ID:AB Intel AboveBoard Plus
Quarterdeck Technical Note
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 multi-task 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" (it means 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.  Any other memory which to
be mapped must be directly above and contiguous with the page
frame.  This perhaps 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 it's boards, defaults the frame to the lowest
possible address.  Upgrade drivers are available from Intel
directly and are posted on their 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 making your Maximum Available in
Conventional Memory, as shown by Memory Status 60K bigger.

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 segements, 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) 1990 by Quarterdeck Office Systems
             * * *   E N D   O F   F I L E    * * *