
	Diagnosing Problems and Optimizing Memory for SGA
	(Sound, Graphics, Aircraft upgrade for FS4)

	Mike Barrs, Assoc.SysOp 76702,1706
	Compuserve Flight Simulation Forum


The SGA upgrade for Flight Simulator 4.0 adds several great new features, 
but getting the most out it requires freeing up as much memory as 
you can. FS4 doesn't support expanded or extended memory and neither 
does the SGA upgrade. So the new sound and graphics drivers must 
compete with ASD and any other FS4 add-ons for memory under the Dos 
640K limit.

If you don't use the Aircraft and Scenery Designer (ASD) you won't 
have too many problems. If you do use ASD with a large memory allocation 
for loading large scenery files, you'll have to work harder to squeeze 
everything into the available memory. The NFL and JFL utilities also 
take up memory space. You might need to remove them to see the new 
SGA goodies and then add them back in once you decide which SGA features 
to hang on to (if you can afford the memory).

The information below is preliminary, based on our first look at 
the SGA upgrade. I'll update it as new information or corrections 
come in. For reasons that will be clear in the SBTALK section below, 
you should avoid using the SBTALK speech synthesizer feature until 
you get everything else working. The only complete system lockups 
I saw while testing were all related to SBTALK.


MEMORY SHORTAGE PROBLEMS

A common problem with SGA is disappearing sound effects. FS4 places 
SGA sound effects on a low priority... it will drop sound effects 
one by one as memory gets tight. The first to go is the landing gear 
sound, then the engine.

If you plan on using the 800x600 cockpit as your standard setup for 
FS4, you'll need the most amount of free memory. The 640x480 747 
cockpit is a close second. You might see sound dropouts or have trouble 
opening the map window with these cockpits until you can free up 
enough conventional memory. Another thing you may notice on the 800x600 
cockpit (and maybe also on the 747 cockpit) is that opening the map 
window may cause the engine sound to disappear and not come back 
until you restart FS4.

These problems will most likely go away if you increase Dos memory 
or switch to the 640x480 or standard 640x350 cockpits which take 
much less memory.


HOW MUCH MEMORY IS ENOUGH

If you have ASD installed, you should try to set up your system for 
at least 620,000 bytes free conventional memory. If you can push 
it to 635,000 or more, that's even better.

You will solve many potential problems by upgrading to Dos 5.0 if 
you haven't already. You will also need to load as many TSR's and 
drivers as possible into high memory, using the loadhi functions 
of either Dos 5.0 or QEMM386 (or equivalent memory manager). Not 
everyone will be able to get 635,000 bytes free, but if your machine 
allows loading TSR's and drivers high, it shouldn't be too difficult. 
If you can't use Dos 5.0's DOS=HIGH command to load Dos into high 
memory, you'll have to settle for fewer SGA features. Try making 
a minimum configuration floppy disk to boot from, with as few drivers 
as possible in the CONFIG.SYS and AUTOEXEC.BAT.

If you need more help in freeing up conventional memory, ask in 
Compuserve FSFORUM section 13 (Hardware) or in the IBMSYS forum.


SGA/ASD COMBINATIONS

With 635,000 bytes free under Dos you can use the following setup:

	ASD: 60,000 bytes static, 30,000 dynamic, 35 dynamic objects
	Soundblaster sampled sounds
	640x480, 640x480 747*, or 800x600* cockpits

	(*no landing gear sound on Soundblaster)

Note that this does not include SBTALK digitized speech or the NFL 
or JFL utilities, and the landing gear sound is missing on the 2 
enhanced cockpits. It is, however, a full ASD configuration that 
will allow loading large scenery files. The 640x480 cockpit works 
fine - it takes less memory so you get all the sounds including landing 
gear.

If you have 590,000 bytes free under Dos, you can use these features:

	ASD: 60,000 bytes static, 30,000 dynamic, 35 dynamic objects
	Soundblaster sampled sounds
	640x480 cockpit

To use the 640x480 747 or 800x600 cockpits, you would have to reduce 
ASD scenery allocations or else give up Soundblaster sound effects.


SBTALKER (for Soundblaster owners)

The digitized speech feature in SGA uses the SBTALKER program included 
with the Soundblaster card (called by the SBTALK.BAT batch file).  
It will automatically load most of itself into expanded memory if 
it finds any on your system, leaving a 6K program kernel resident 
in conventional memory.

The SGA manual recommends that you prevent auto-loading of SBTALK 
into expanded memory by disabling your expanded memory driver, but 
the manual is assuming you don't have ASD installed! Without expanded 
memory, SBTALK hogs 184K in conventional memory. FS4 won't even boot 
up with ASD installed, when SBTALK is using that much memory.

You might be able to load all of SBTALK into high memory, moving 
that 6K kernel out of conventional memory... I tried using QEMM386's 
Optimize program to do that but it failed to load it high.

SBTALK will run fine in expanded memory but you need to follow a 
few steps to avoid problems. If you load SBTALK from inside your 
Soundblaster subdirectory, FS4 will lock up solid, either right away 
or when you first get an ATIS or COM message. You need to use the 
modified BLASTER.DRV driver installed into your FS4 subdirectory 
by SGA, not the BLASTER.DRV included with the Soundblaster. Easiest 
way to do this is to copy SBTALK.BAT, SBTALKER.EXE, and REMOVE.EXE 
from your Soundblaster subdirectory into your FS4 subdirectory. Then 
log onto your FS4 subdirectory and type "sbtalk". This way it will 
grab the new driver supplied in the upgrade. After running FS4 remember 
to type "remove" in the FS4 directory to remove the driver.

You'll want to write a batch file like this to run FS4 if you decide 
to keep SBTALK in your configuration... change the path names as 
necessary for your system:

@echo off
cd\fs4
call sbtalk
fs4
remove

SBTALK digitized speech will pause the simulation while talking (at 
least it does on my machine) and the synthetic "robot" speech is 
hard to understand. Unless this voice synthesizer feature really 
knocks you out, I would recommend not using it at all. The sampled 
engine and other sounds in the SGA package are much better.


TSENG 4000 GRAPHIC CARDS

The list of supported video cards and available features on page 
11 of the SGA manual is self explanatory except for the "Super VGA 
with Tseng Chip Set" category.  In FSFORUM these are usually called 
Tseng 4000 cards and include the Orchid Prodesigner II, the Diamond 
Speedstar, and many new inexpensive "no-name" Super VGA cards using 
the Tseng 4000 VGA chip set. If you're looking to upgrade from a 
standard VGA card to a fast Super VGA card, I recommend the Diamond 
Speedstar... it's very fast, has good Windows drivers, and it's the 
least expensive of the name brand cards.


PROBLEMS, BUG REPORTS, WORKAROUNDS

Some Soundblaster owners have experienced the aircraft "bobbing" 
mentioned in the SGA README file. The cure seems to be to plug the 
joystick into the Soundblaster port rather than use another game 
card. Others are using Soundblasters with the joystick plugged into 
a multi I/O card joystick port with no trouble.

The numlock key for toggling the map display on and off does not
work with the 640x480 747 or 800x600 cockpits. Use the 2,8 menu choice 
instead. The 747 cockpit has no separate map window, it uses the 
MFD display in the instrument panel for the map.

The low altitude warning horn on the 800x600 display only works 
intermittently.

The sampled tire chirp sound for Soundblaster owners loads from disk 
the first time it's used. This can cause an annoying delay the first 
time you land. As a workaround, Rick Lee suggests saving a startup 
mode where your airplane is a foot off the ground (use the 5,A menu 
to adjust the altitude). When FS4 boots up, your plane will settle 
to the ground and trigger the chirp. From then on, the tire chirp 
is in memory and you shouldn't hear a delay when it sounds on touchdown.

The instrument panel in the 640x480 cockpit has a "squashed' look... 
the gauges are oval, not round, even when your screen is correctly 
sized for a 640x480 display. The proportion was checked by viewing 
a multisided building in the ASD editor's overhead view. The building 
appeared as a circle, not an oval.  So apparently the oval gauges 
are "normal" for this display.

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For any questions on Flight Simulator, Aircraft and Scenery Designer, 
or the new SGA upgrade, ask in the appropriate section of Compuserve 
FSFORUM and the members there will be glad to help.

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This article copyright 1991 Mike Barrs, all rights reserved.

