ID:AS IBM AS/400 Terminal Emulation Setup
Quarterdeck Technical Note #212 Filename: AS400.TEC
by Dan Sallitt CompuServe: AS400.TEC
Last revised: 8/18/92 Category: SW3
Subject: Using Quarterdeck products with IBM's PC Support AS/400 / 5250
terminal emulation software and hardware.
The IBM AS/400 is a terminal emulation setup akin to the 5250. It usually
requires two or three files in config.sys and two loaded from the command line
to get it going, followed by a number of other files to implement various
The sizes of the basic AS/400 files that are listed below are accurate for the
early 1990 versions of IBM's AS/400 software. Some of these files are smaller
in later releases.
ECYDDX.SYS 21K - a block device, which means that
Quarterdeck's DEVICE.COM cannot load it
from the command line
FSDD.SYS 59K - only needed to create virtual drives
on the AS/400. ECYDDX.SYS must be loaded
before it. Later versions of the AS/400
software may replace FSDD.SYS with the TSR
E5250AH.COM 8.2K - manages the PC's terminal emulation
hardware. Different cards can be used for
AS/400 connection, and each requires a
different TSR to manage it - this file
manages the 5250 card. A TSR that is
often used instead of E5250AH.COM is
1) One of the cards that the AS/400 software can use, the 5250 card (and maybe
others as well), puts a piece of RAM, 8K or so in size, at xC00 (usually
CC00). QEMM-386 and other memory managers may not see this RAM. In addition
to excluding this area on your memory manager, you should probably use the RAM
parameter with QEMM-386 (or, if you are on an 8088 or 80286 machine and using
a memory manager that provides mappable pages between 640K and 1024K other
than the page frame, use Quarterdeck's QEMM-50/60 or QRAM to map these pages).
Otherwise, E5250AH.COM may access various sections of the reserved memory area
when it loads, and DESQview's XDV may crash on startup if all these areas
aren't excluded. Loading Quarterdeck's Manifest after you load E5250AH.COM,
and examining the QEMM-386/Analysis screen, is a good way of finding out what
areas to exclude. The Analysis screen may advise you to exclude some areas
inside the expanded memory page frame as well as mappable areas outside the
page frame; it should be necessary, however, only to exclude areas outside the
page frame. The Quarterdeck Technical Bulletin #219, "Using QEMM-386's
Analysis", describes this process in more detail.
Giving E5250AH.COM the parameter /Mx (where x is the same as above-C by
default) seems to make it access fewer areas, though the areas that are
accessed still need to be excluded if you don't use the RAM parameter or
otherwise map all available areas between 640K and 1024K before the AS/400
For example - if you are using QEMM-386 and IBM's 5250 card and have
determined that the card uses the CC00-CDFF area, your QEMM-386 line in the
CONFIG.SYS file should look like this:
DEVICE=C:\QEMM\QEMM386.SYS RAM X=CC00-CDFF
...and you should load E5250AH.COM with the following parameter:
You should then examine QEMM/Analysis screen, and put further exclusions on
QEMM if any areas on this screen (other than the page frame area) are labeled
2) In earlier versions of IBM and Quarterdeck's software, STARTRTR did not
like to load inside DV, which meant that everything before it couldn't load in
DV. Even at that time, many other AS/400 functions loaded after STARTRTR
would load in a window - we have seen STF.COM load and run in a DV window. We
have verified that the version of STARTRTR dated 5-26-90 can run successfully
inside a DESQview 2.31 window. We are not sure whether revisions of STARTRTR
or of DESQview were responsible for resolving early conflicts.
On one system that we saw, STARTRTR used an interrupt that can cause conflict
with DESQview (INT 69). Because it is likely that DESQview will always avoid
using this range of interrupts when the AS/400 drivers are loaded in the
CONFIG.SYS file, this is probably not a problem for current DESQview users.
However, users of DV 2.30 and later can do themselves no harm by giving
DESQview the startup parameter /XB:68 when they run STARTRTR inside DV.
3) On some systems, after STARTRTR is run, users run a program, FSPC.COM, to
make a virtual disk on the mainframe. This program isn't resident and takes
no memory. However, FSPC needs to see FSDD.SYS, and in earlier versions of
the IBM and Quarterdeck software it couldn't from inside a DV window. We
believe that this is no longer a problem with DESQview 2.31 and the mid-1990
release of the AS/400 software.
4) STARTRTR will need 160K of space to load high, even though it only uses 56K
or so after it has loaded.
5) Some AS/400 drivers and TSRs know about expanded memory and store something
there. Therefore, some of the memory figures that I've quoted may increase in
the absence of expanded memory.
6) If you run the AS/400 software inside DV, it may or may not be necessary to
set Keyboard Conflict to 8. One user thought he needed it set to 9, though
this report is not substantiated.
7) In some versions of the IBM AS/400 software, the driver FSSD.SYS and the
non-resident FSPC.COM are united in a smaller TSR STARTFLR.COM. Early
versions of STARTFLR crashed in a DESQview 2.26 window in much the same
preemptive way that early versions of STARTRTR did; we have reason to believe
that, even on systems in which STARTRTR runs successfully in DESQview,
STARTFLR may fail in a DESQview window when QEMM-386 is present and in an ON
state. We have heard that some 1991 versions of STARTFLR may run in DESQview;
this is not yet confirmed.
8) When loaded high with QEMM-386 version 5.00, ECYDDX.SYS would fail with an
error message like "Keyword invalid." QEMM-386 versions 5.11 and higher are
able to load ECYDDX.SYS high successfully. It is possible that including a
single space after the word ECYDDX.SYS on the appropriate line in the
CONFIG.SYS file may help load ECYDDX high, but this has not been tested.
9) The AS/400 utility STF has difficulty loading high with both QEMM 5.00 and
QEMM 5.11. QEMM's LOADHI /GS feature reports that a version of STF from mid-
1990 needs a region of approximately 26K to load successfully; however, on at
least one system, this version of STF.COM reports that it has insufficient
memory to load even when loaded into a 79K region of High RAM. It is possible
that STF.COM is making the assumption that it will be loaded below 640K, and
is becoming confused when loaded above 640K; it is also possible that LOADHI
/GS is somehow not detecting the correct amount of memory that STF.COM needs
to start up. We have not investigated this further at the time of writing.
10) You may instruct EIMPCS not to use expanded memory by using the "p=0"
switch on it. This may solve some problems you have using AS/400 with an
expanded memory manager.
*This technical note may be copied and distributed freely as long as it*
*is distributed in its entirety and it is not distributed for profit. *
* Copyright (C) 1991-2 by Quarterdeck Office Systems *
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