
RESET  --  Utility to reset the Tandy 640x200x16 (TGA) video mode to CGA
 
Version 1.0 
 
By Christopher J. McConnell 
 
Email: cjmnews@netscape.net 
 
      The purpose of RESET is to provide a way to reset the Tandy high
resolution video mode (TGA) to the lower modes without having to enter and exit
Deskmate.
 
      The inspiration for this program came from a using Fractint and Cshow
on my Tandy 1000 TL and I couldn't switch from TGA to CGA without exiting the
program, entering Deskmate, exiting Deskmate, and re-entering the program. 
So I wrote this program so I can reset my video mode without Deskmate.  In 
fact because of this program I have deleted Deskmate entirely from my system.
 
   For those interested, here is more detail on the problem.  When a third 
party vendor of software figures out how to get into and use the TGA mode,
they figure that Tandy would keep their video modes standard enough for the
standard exit.  The standard exit procedure is to leave the video mode in it's
current settings, because a new video mode will reset the registers to what
is needed.  This is not the case with TGA and CGA.  To change to CGA from TGA,
one has to manually reset certain registers that CGA can't touch because these
registers are non-IBM compatible.  Thus the registers remain set for TGA and 
one get's garbage on the screen when you try to use CGA after using TGA.  Tandy
did know about this side effect, and took the initiative to reset the video 
upon exit of Deskmate.  This way Tandy could claim full IBM compatibility on 
CGA and still have their TGA mode.  RESET restores the registers used for TGA 
to settings that are compatible for CGA, so now one can see both kinds of
graphics without too much hassle.

   I use RESET in two ways, the first is to have RESET in a batch file that
runs Fractint (for example) like this:

        FRACT.BAT
             c:
             cd \games\fractint
             fractint
             reset

   This will reset your video mode automatically every time you exit Fractint,
so when you go to play another game, your video will look the way it's supposed
to.

   The second way I use RESET is after viewing a fractal or gif in TGA, I'll
select CGA mode, shell out to DOS, run RESET, go back into the program, and
see my fractal or gif in CGA.  Some programs like Fractint have a shell to DOS
function built in, some like CSHOW do not, so you may have to pick up a hot-key
program that will shell to DOS so you can shell out to do this.
 
Terms and Limitations:  This utility is only meant to be executed on the 
                        Tandy 1000 series of computers.  I have not tested
                        it on any other series of Tandy, and since these
                        registers are Tandy specific then running RESET
                        on any other type of computer would be senseless.
                        Unpredictable results will happen on non-Tandy
                        computers.
 
                        This software is "AS IS". 

                      
