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The Apogee FAQ

[6.4.2] Setting the BLASTER environment variable

This section may be useful if you are having problems with sound or music in
a DOS-based Apogee game.  If you're trying to run a Windows-based game, this
section does not apply to you.

Apogee's DOS games that use Soundblasters look at the BLASTER environment
variable to figure out where to send its sound output.  Check to make sure
that you have the SET BLASTER line in your AUTOEXEC.BAT file.  This code is
an example and probably isn't exactly what you need to put in your system.

Note that this BLASTER environment variable applies for many Apogee games
regardless of whether or not you have an actual Sound Blaster card or not.
These settings tell the game how your sound card is configured, regardless of
what brand it actually is.

SET BLASTER=A220 I5 D1 T3 P330 H6 E620
 |    |     |    |  |  |  |    |  |
 |    |     |    |  |  |  |    |  |_______ AWE 32 Only Parameter
 |    |     |    |  |  |  |    |__________ "High" DMA Channel
 |    |     |    |  |  |  |_______________ MIDI Port
 |    |     |    |  |  |__________________ Type of Card
 |    |     |    |  |_____________________ DMA Channel
 |    |     |    |________________________ Interrupt
 |    |     |_____________________________ Port Address
 |    |___________________________________ Environment Variable
 |________________________________________ DOS Command

NOTE: There can be no spaces between the word BLASTER and the equal sign (=).
If you have a space in there, your system will read the parameter incorrectly,
and it will not be recognized by our games.

(Some of these parameters (P, H, and E) are dependant on certain types of
cards.  For example, the E is only needed if you have an AWE 32.  The
minimum requirements are to have the A, I, D, & T parameters.  The other
three may or may not be needed depending on what type of card you have.
Please read this entire section to see if you need any of them.  If you
are using a clone card, or some card that's not a "true" Soundblaster,
then you will most likely only need A, I, D, and T.)

Now, these may not (most likely not) be the same for your board, because the
Port Address, Interrupt and DMA Channel can be set by adjusting "jumpers" on
your sound board.  Some newer cards have this information controlled by
software, please consult your card's manual for more information on how to set
these things.  You should also check your manual if you are unclear as to how
to tell what settings your card is set at.  The information *IS* important, so
it's recommended that you know precisely what the settings are.  If you are
using a card that "emulates" the Soundblaster (such as the Gravis UltraSound
through software, or the PAS16), you should check your card's manual on how to
set the card for Soundblaster emulation.

For PORT ADDRESS, it's almost always 220.  That seems to be the default for
most sound cards out there, and unless you know you've switched it away from
220, it's a safe bet it's still there.

The INTERRUPT is something that varies from system to system.  Mystic Towers
and games prior to Raptor require that your IRQ be set at 7 or less.  Apogee
does not recommend using IRQ2, as it causes problems.

The DMA CHANNEL sometimes causes problems if it isn't set to 1, which is the
usual default.  If it is not set correctly, some Apogee games may lock up
when the sound is turned on.

The TYPE OF CARD should be 1 if you have an older Soundblaster, or a Sound
Blaster emulating card.  Use 3 if you have a newer plain Soundblaster.  Use
2 for an older Soundblaster Pro.  Use 4 for a newer Soundblaster Pro.

The MIDI PORT parameter will only be needed if you are using a card that has
MIDI capabilites.  If so, this is where you define what MIDI port you are
using.  330 seems to be the default, so if you have a MIDI card, and you
haven't changed anything from factory defaults, this is probably where it still

The HIGH DMA CHANNEL is something that is used primarily on Soundblaster 16
cards.  This is not the same as the standard DMA channel, this is a different
one.  This is only used if you're using a 16 bit sound card capable of playing
16 bit Soundblaster sounds.  By default, this is usually 5, so unless you know
that it's something else, it's probably still 5.

The E620 parameter is something that is needed _only_ if you have a Creative
Labs AWE 32 sound card.  If you have one of these, this parameter will have
been set up properly assuming you've installed the software that came with the
card.  Check your AWE 32 documentation for a more thorough explanation of what
this parameter is used for.

Note on the Soundblaster AWE64:  The AWE64 will not always correctly set up
its sound drivers for use in Windows 95 in relation to DOS games.  There is
information on how to get around this in the README.TXT file that is installed
on your hard drive in the AWE64 driver directory.

Note on Hocus Pocus:  This game was made when there were only four possible
parameters for the BLASTER environment variable (A, I, D, and T).  Due to the
way the game parses the variable, the game probably won't work correctly
unless the BLASTER environment variable ONLY has those four parameters and
no others.  One way to work around this conveniently is to write a batch file
for the game that sets the BLASTER variable so it only contains these four
parameters, runs the game, and then restores the settings afterward.

After you have entered the correct SET BLASTER line in your AUTOEXEC.BAT
file, make sure you save the change, delete the game's config file (????.CFG),
and reboot before you try playing the game again.

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      [6.4.3] Slowing down your computer to play old games

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