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ANSI Music - The Technical Details
ANSI is an acronym for "American National Standards Institute" and
actually has little to do with this "ANSI music" stuff. However, the
American National Standards Institute defined a set of codes for
terminals to provide a standard for cursor control. This was expanded to
include graphics modes and color with the release of the ANSI.SYS device
driver. It wasn't actually ANSI who expanded the set of codes to include
the graphics, which are specific to IBM compatible computers with
certain video adapters, but the name ANSI stuck. The original purpose of
ANSI cursor control was to give mainframes a way to control the cursor
on various terminals connected to them. The purpose of the ANSI.SYS
driver was to give programs a simple and compatible way of controlling
the video screen. However, it seems that the only real use for ANSI has
been to give BBS's the ability to control the screen colors and cursor
positioning. This even led to a new artform, but let's not even think
about that. It's too much like Art Deco. In CGA color, no less.
The ANSI.SYS driver also includes provisions for redefining keys
on the keyboard. This can be used for character translation or to create
simple macros. It has even been used to create trojan text files that
redefined your keys to destroy data (i.e. your enter key becomes "DEL
*.* <return> Y <return>"). Watch out for this kind of thing. It's not
hard to do.
Now I said that the actual "ANSI" organization had little to do
with "ANSI music." The reason that the music codes were given the name
"ANSI" is because they start with the same escape sequences. All ANSI
codes start with <esc>[ as do the music codes. What I mean by <esc>[ is
the escape character (27 decimal, 1E hex) and the open-bracket
character. Now, on to the REAL details of ANSI music.
As I just got through saying, ANSI music starts with the
characters <esc><open-bracket>. An ANSI music sequence ends with the
character <control-N> (14 decimal, 0E hex). In between, the commands are
exactly the same as those used for the "PLAY" command in BASIC. Now you
can just look up the PLAY command and you know most everything you need
to know about ANSI music. But for those of you still confused, I'll
summarize the PLAY commands and give a few examples and pointers. Here
we go:
The PLAY commands are pretty simple. This info was taken from the Tandy
BASIC reference manual, but the Tandy-specific commands are not
recognized by ANSI music and will be left out. Here we go again:
A - G Plays the notes corresponding to the notes A-G on the musical
scale. A # or + after the note makes it sharp, and a - makes
it flat.
Ln Sets the duration of the notes that follow. n is a number from
1 to 64. 1 is a whole note, 2 is a half note, 4 is a quarter
note, 8 is an eighth note, etc.
On Sets the current octave. There are 7 octaves, 0 through 6. The
default octave is 4. Each octave starts with C and ends with B.
Octave 3 starts with middle C.
Nn Plays a note. n is in the range 0 to 84. Instead of specifying
the note's letter and octave, you may specify the note's number.
Note zero is a rest.
Pn Plays a rest (if that's the right terminology). n is the same as
for the L command, but specifies the length of the rest.
. Plays the note as a dotted note. You music buffs know that means
that the note is one half it's length longer when dotted. Place
the dot after the note, not before it. More than one dot may be
used after a note, and dots may be specified for rests.
MF, MB I'm not sure these options work. Music Foreground and Music
Background. Supposedly these options will let you specify
MF and have the computer stop whatever it's doing and play
the note, while MB lets the computer do whatever it was doing
and play the note at the same time, kind of lo-tech multitasking.
The default (for BASIC anyway, and it seems for ANSI-music) is
Music Background.
MN "Music Normal." Each note plays 7/8 of the duration set by the
L command.
ML "Music Legato." Each note plays the full duration as set by the
L command.
MS "Music Staccato." Each note plays 3/4 of the duration set by the
L command.
That's it for the basic set of commands. There are other options
in BASIC that are unusuable in the ANSI music, such as the X command
which lets you include a variable name in the play command, where a
string variable name is given and the string contains a series of play
commands. Another command which is usable only on a Tandy or other
computer with the TI sound chip (the PCjr, for instance) is the V
command, for setting the volume of the sound. Now for some examples.
<esc>[cdefgab<control-n> plays the notes "cdefgab" (the entire octave) on
the default octave 4.
<esc>[l4al2cl8e<control-n> plays a quarter-note A, a half note C, and an
eighth-note E. Not too musical, but an
example nonetheless.
I'm not one for giving too many examples, I think that's plenty
for you to get the basic idea. Try it in BASIC before you try it as an
ANSI code in a message/picture. Just type PLAY "ABCDE" <return> and put
whatever you like in the quotes. That's the easiest way to work out the
notes and get the timing right before you blast it up to your favorite
BBS.
*********** Closing Comments ***********
I only know of two major comm programs that support ANSI music:
TeliMate and Qmodem. I personally prefer TeliMate. If we (the collective
we, that is) spread the use of ANSI music, hopefully the makers of other
comm programs will incorporate this feature. If the makers of Telix and
Procomm included this, that would cover 95% of IBM compatible BBS'ers. A
new version of Telix is due out in a few months and I'm hoping this new
version will add ANSI music. I gave up Procomm years ago, so I don't
really know when a new version of that's due out, but it still seems to
be the most common terminal program around. Still, TeliMate is gaining
popularity for its mouse support and multitasking ablility (I wrote most
of this document while downloading a 371k file at 1200 baud), and Qmodem
is pretty popular already.