ORIGINALLY PUBLISHED IN LIMA NEWSLETTER DECEMBER 1991
 
          OLD TRICKS FOR NEW (and not so new) USERS  
                       by Joseph Cohen 
                     Lima Ohio User Group 
      
     Thou manu of us tend to ignore most of the cartridge
software for our computer, with the exception of TI Extended
Basic and, possibly, Multiplan, Logo II, Editor/Assembler,
and TE-2 (for speech), many of the cartridfges are very
enjoyable.  In order to give you an excuse for searching
your vlosets and basements looking for those hidden modules,
I'd like to point out that many of them have undocumented
features ranging from useful to interesting to amusing.
Here are a few examples. 
      
     many are probably familiar with "The Secret of Personal
Record Keeping: Implementing DISPLAY AT and ACCEPT AT
without Extended BASIC", published way back in 99'er
magazine and reprinted in The Best of 99er, p. 76.  Briefly,
TI BASIC with the PRK module contains the commands CALL D()
and CALL A() (similar to DISPLAY AT and ACCEPT AT).
Presumably this also works with the Statistics module, but I
do not have this one and could not verify it.  I have been
told that this is a result of the hybrid nature of certain
modules, containing both GPL and BASIC coding.  Perhaps
someone knows or could discover additional undocumented
features of this cartridge (I have extra PRK modules if
anybody would like to experiment with it), and possible
other cartridges which cvall console BASIC routines (E.G.
Tax/Investment Record keeping). 
      
     Next, the TI Disk Manager cartridge offers a
proprietary protection feature that does not allow the Disk
Manager to copy a protected diskette.  To use it, press the
FCTN-X key ten times while on any menu screen.  You will
hear a beep (if your monitor has sound!) and >< will appear
at the center top of the screen.  Any diskettes initialized
at theis point will be proprietary protected.  Each time you
address them using the Disk Manager cartridge (e.g., to
catalog such a diskette), a low-tone beep will sound (not
present for unprotected diskettes), informing you that the
diskette is protected.  The protection information is stored
in sector 0 on the diskette.  This type of protection is
ineffective against the sector disk copiers and has been
discussed in the past.  I wonder of anybody knows more about
it.  The DM-1000 offers protection and un-protection of
diskettes; is it the same kind as the TI Disk Mangager
cartridge? 
      
     Now to a few game cartridges.  Moonmine, Alpiner,
Munchman, Munchmobile, and Hooper have a test mode, where
you can select the starting level.  So if you wanted to see
what it is like to play at those levels you could never
reach, here is a good reason to plug those cartirdges into
your 99/4A!  The test mode is obrained by pressing SHIFT/8 3
8 at the game title screen (SHIFT/8 only, for Hopper).  and
on Burgertime, pressing SHIFT/8 gives a message: "code
modifications by John M. Phillips".  Have you always played
Parsec as a one player game?  Here is something different,
for a two player team.  If the fire buttons on both
joysticks are pressed simultaneously, Spaceship Parsec will
not overheat.  Horizontal lines will appear on the screen,
but they do not disturb the game and would allow, in fact,
one to see the Bynites when they turn invisible. 
      
     This is certainly not an exhaustive list.  If anybody
knows about other "tricks", would they please let me know?
[Ed note: Mr. Cohen can be reached at the newsletter
address, P.O. Box 647, Venedocia OH 45894].  I am sure the
Adventure and Tunnels of Doom modules contain undocumented
features.  Please take a few moments to let others know, and
enjoy your cartridges! 
     .PL 1