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			*	SOUND6D      *
			**********************

by  Laurent PONCEY  <laurent.poncey@ecl2001.ec-lyon.fr>      
(09/19/1998)

What is new in sound6d.92p ?
   Nothing except my e-mail...
   All programs are the sound6c 's one.

What is it ?
   Sound6c.92p is a small program that plays a song.
   Note6c.92p allows you to tune up the program if necessary (only for
     programmers).

Improvements
   It plays a two-part song, whith REAL CHORDS.
   The sound is quite smoother than the previous version: Sound5b. It's
     now a nice square wave.

How to use it
   It should work well both on a TI-92 I and a TI-92 II.
   I have a TI-92 II so frequencies may be false on a TI-92 I.
   A basic cable like the one Tim Gerla describes works well.
   Run sound6c.

About cables
   You can hear a STEREO sound OR chords: it depends on the resistors
     you use !
   Here are the scheme of my connector:

               --- Red ----[/\ R1 /\]---      
              /                         \     
    2,5 mm   /                           \                  3,5 mm
   /-------|-                             ----- Right ----|-------/
   |TI-Plug|--- Ground ----[/\ R2 /\]--------- Ground ----|        
   \-------|-                             ------ Left ----|-------\
             \                           /   
  stereo      \                         /                 stereo plug
   plug        - White ----[/\ R1 /\]---     


  Hearphones:

                 -----------
                /           \
               /            (o)   Right speaker
     /-------|-             /
     |       |--------------
     \-------|-             \
               \            (o)   Left speaker
                \           /
                 -----------
 

   Red, Ground, and White are coming from the TI 2,5 mm plug.
   For R1, I use a 100 k stereo potentiometer, and a 100 k mono one
     for R2.
   For the 2,5 mm plug, you'd better cut your TI to TI cable: those
     plugs you can buy everywhere are too small, and sometimes make
     your TI crash if you move them in the TI plug !
   For a STEREO sound, choose R1>R2 : the current goes in each speaker,
     and then comes back in the ground cable.
   For CHORDS, choose R2>R1 : the current goes through both speakers,
     and you've got real chords.

   If your TI doesn't answer any more, it is because R1+R2<7 Kilo Ohms.
     Increase R1 or R2 in order to unlock it, or unplug your cable.

How it makes sound
   My program uses the outport: for each cable (red or white), you can
     set the corresponding outbit to 0 or 1. It only plays each part of
     the song on each cable, and that's the hearphone that mix them.

For TI-I, how to change frequencies
   Use the note6c program, and report the frequencies corresponding to
     C, C#, ..., B for the 4 octaves. And them put them at the end of 
     my program in "freq".

About the program
   Feel free to use my program or parts of it (please just mention they
     are mine ! Thanks !).
   I'm interested in good improvements, and I would be really pleased 
     if you could give me good ideas.

Great thanks to
   David Ellsworth
   Markus Klisics
   Tim Gerla
   ...

E-Mail
  You can e-mail me at laurent.poncey@ecl2001.ec-lyon.fr
  I will attempt to answer all e-mails. :-)