
        Using the Media Vision ThunderBoard Card with OS/2 2.1
		     Version 1.0	dated 7/26/93
  	------------------------------------------------------

As many of you know, Media Vision has perfected Sound Blaster compatibility
and all of our sound cards that claim 100% Sound Blaster are, in fact,
compatible at the hardware level.  

Paradoxically, the SoundBlaster driver that ships with OS/2 2.1 (SBD2.SYS) 
does not work with the Media Vision ThunderBoard nor the SoundBlaster 
section of the Pro AudioSpectrum 16, even though the hardware is the same.

Here's the reason why:  When Media Vision cloned the original Sound Blaster
(calling our clone 'ThunderBoard'), we added some extra features. For example,
the ThunderBoard has the ability to record at up to 22KHz.  We needed a way
to check whether the card in the system was a Sound Blaster or a ThunderBoard
to determine whether or not to allow the enhanced functionality.  

The method we came up with was to have a 'hidden' version number.  The first
time a program asks a ThunderBoard (TB) for its version number, the TB
returns the same value the Sound Blaster returns.  The second time, the TB 
returns its own version number (which is different from the Sound Blaster 
version number.)

The Sound Blaster people discovered our trick and now they put a _double_ 
version check into their code to detect the ThunderBoard.  We think
that's a fair and reasonable thing to do, as long as they don't crash the
user's system or do anything else destructive.  Claims that the ThunderBoard
isn't 100% compatible are obviously misleading.

The OS/2 driver peforms a double version check and so it's possible to bypass
the second check and allow the ThunderBoard to work.  All that is necessary
is to change a single byte.  We're telling you which byte it is here so that
you can verify the change or perform it yourself.  We've also supplied a
patched version so that you can avoid the details and just start using the
driver.

The byte to change is at offset 3ED8 (hexadecimal) in the file.  Change
the value from AB to 00.  Here's how to install the patched driver.

First, make sure you've installed the MMPM/2 SoundBlaster driver. 

Before installing the Sound Blaster driver, be sure you know what
the IRQ jumper setting is for your ThunderBoard.  Use the MINSTALL
program to install the SoundBlaster driver.  After all files have been
copied to your system, a Window entitled "Sound Blaster Installation" will 
appear.  It will ask you to select which type of Sound Blaster card is
to be installed.
  Choose the:

	Sound Blaster (ISA and MCV)

  selection.  Be careful.  The default choice is 
  'SoundBlaster Pro (ISA with OPL2)' and that driver will not work.

  Then you will be asked how many Sound Blasters are installed.  Select 1.

  The next screen asks you for the DMA, I/O Address and IRQ.  Most cards
  should be set to DMA 1 and I/O address 220.  Some ThunderBoard owners
  may need to change the IRQ setting to 5 or 2.  Those are the only other
  choices that the driver offers.  

When the Installation program has finished, go to an OS/2 command window
and perform these commands:

[C:\]cd \mmos2
[C:\MMOS2]copy sbd2.sys sbd2.old
[C:\MMOS2]copy a:\sbd2.sys 

The last command assumes the patched SBD2.SYS file provided with this 
document is on the A: drive.  If it is not, substitute the proper path
to the patched file.

Now reboot your computer and you should have sounds.


If you wish to patch the Sound Blaster driver yourself, here's how:
Remember that symdeb and debug adds 100h bytes to the offset so the byte
you must change will be at offset 3FD8.

    Start a DOS session.

    [C:\]cd \mmos2
    [C:\MMOS2]copy sbd2.sys sbd2.old
    [C:\]debug sbd2.sys
    -e 3fd8 00
    -w
    Writing 8A7A bytes
    -q

If the above Debug session does not make sense to you, do not attempt the
patch yourself.  Ask a DOS expert.


MISCELLANEOUS NOTES:

   *  Digital audio appears to work fine.  

   *  FM synthesis (MIDI player) doesn't appear to work.  We don't know why.
      If you get it to work, let us know.

   *  In theory, this driver should work on the Sound Blaster section of the
      PAS 16.  This would allow you to have two Sound drivers working 
      at the same time in MMPM.  We have not tested this. If you get it
      to work, let us know.  If you can't get it to work, we don't want to 
      know.

   *  The ThunderBoard does not have a MIDI interface!  Do not waste your
      time or money trying to use a MIDI connector box.

   *  Since we have only patched this driver and don't have the ability to
      modify the original source code, do not expect any bug fixes or 
      changes to come from Media Vision.  

   *  Media Vision's Tech Support department will not be able to assist
      you with this driver.  If you have comments or questions about this
      driver send them to:
		Internet: 75300,2772@compuserve.com
		CompuServe: Media Vision [75300,2772]
		FAX: (510) 226-2582, Attn. OS/2 engineering	

   *  Many people have asked whether Media Vision will write a ThunderBoard
      driver for OS/2.  The answer is 'probably not'.  We recommend that our
      ThunderBoard customers upgrade to the Pro Audio Spectrum 16.  Prices
      in computer specialty stores have been as low as $139.  That's an 
      excellent price!  And the PAS 16 is fully supported under OS/2.  Even
      the SCSI interface.

  If you'd like to learn more about Media Vision's products, call our
  Sales department.

 Media Vision, Inc        Main:         (800) 348-7116 or (510) 770-8600                                   
 3815 LaurelView Ct.      Sales:        (800) 845-5870
 Fremont, CA 94539        FAX:          (510) 770-8648 or (510) 770-9592

     Customer Service and Tech Support: (800) 638-2807 or (510) 770-9905
     ISV Relations and Developer Assistance: (800) 472-6147

 BBS: (510) 770-0968 2400 
      (510) 770-0527 9600 

     There are a total of 8 lines and all lines support 
     8 bits, no parity, 1 stop bit, 300 - 14,400 bps


 CIS: GO MEDIAVISION or send CIS mail to 75300,2772

 European Customers:

                Media Vision Technology GMBH
                Raiffeisenalle 16
                8024 Munchen-Oberhaching
                Germany

                Main:                       89-61381-175        
                Tech Support:               89-61381-167
                FAX:                        89-61381-174        









