beep_morse_code.sh

#!/bin/bash

if [ -z $1 ]
then
	echo "Usage: morse.sh <string in quotes> <words per minute (optional) > <beep frequency (optional)>"
	exit 1
fi

if [ -z $2 ]
then
	WORDS_PER_MINUTE=25
else
	WORDS_PER_MINUTE=$2
fi

if [ -z $3 ]
then
	FREQ=600 # The frequency we want beep to use, 600-800 is typical
else
	FREQ=$3
fi

DOT_LENGTH=$((1200 / $WORDS_PER_MINUTE ))
MESSAGE=$(echo $1 | awk '$1=$1 {print toupper($0)}' FS= OFS=";");
MESSAGE=$(echo $MESSAGE | awk '$1=$1' FS=' ' OFS='WORD');
MESSAGE=$(echo $MESSAGE | sed 's/0/ZERO/; s/1/ONE/; s/2/TWO/; s/3/THREE/; s/4/FOUR/; s/5/FIVE/; s/6/SIX/; s/7/SEVEN/; s/8/EIGHT/; s/9/NINE/;');	
#echo $MESSAGE # for debugging

DOT() {
	beep -f $FREQ -l $DOT_LENGTH -D $DOT_LENGTH;
}
DASH() {
	# A dash is 3 dots
	beep -f $FREQ -l $(( DOT_LENGTH * 3 )) -D $DOT_LENGTH;
}
LETTER() {
	# The space between letters is one dash
	beep -f 1 -l $(( DOT_LENGTH * 3 ))
}
WORD() {
	#Space between words is 7 dots
	beep -f 1 -l $(( DOT_LENGTH * 7 ))
}

A() {
	DOT; DASH;
	LETTER;
}

B() {
	DASH; DOT; DOT; DOT;
	LETTER;
}
C() {
	DASH; DOT; DASH; DOT;
	LETTER;
}
D() {
	DASH; DOT; DOT;
	LETTER;
}
E() {
	DOT;
	LETTER;
}
F() {
	DOT; DOT; DASH; DOT;
	LETTER;
}
G() {
	DASH; DASH; DOT;
	LETTER;
}
H() {
	DOT; DOT; DOT; DOT;
	LETTER;
}
I() {
	DOT; DOT;
	LETTER;
}
J() {
	DOT; DASH; DASH; DASH;
	LETTER;
}
K() {
	DASH; DOT; DASH;
	LETTER;
}
L() {
	DOT; DASH; DOT; DOT;
	LETTER;
}
M() {
	DASH; DASH;
	LETTER;
}
N() {
	DASH; DOT;
	LETTER;
}
O() {
	DASH; DASH; DASH;
	LETTER;
}
P() {
	DOT; DASH; DASH; DOT;
	LETTER;
}
Q() {
	DASH; DASH; DOT; DASH;
	LETTER;
}
R() {
	DOT; DASH; DOT;
	LETTER;
}
S() {
	DOT; DOT; DOT;
	LETTER;
}
T() {
	DASH;
	LETTER;
}
U() {
	DOT; DOT; DASH;
	LETTER;
}
V() {
	DOT; DOT; DOT; DASH;
	LETTER;
}
W() {
	DOT; DASH; DASH;
	LETTER;
}
X() {
	DASH; DOT; DOT; DASH;
	LETTER;
}
Y() {
	DASH; DOT; DASH; DASH;
	LETTER;
}
Z() {
	DASH; DASH; DOT; DOT;
	LETTER;
}

ZERO() {
	DASH; DASH; DASH; DASH; DASH;
	LETTER;
}
ONE() {
	DOT; DASH; DASH; DASH; DASH;
	LETTER;
}
TWO() {
	DOT; DOT; DASH; DASH; DASH;
	LETTER;
}
THREE() {
	DOT; DOT; DOT; DASH; DASH;
	LETTER;
}
FOUR() {
	DOT; DOT; DOT; DOT; DASH;
	LETTER;
}
FIVE() {
	DOT; DOT; DOT; DOT; DOT;
	LETTER;
}
SIX() {
	DASH; DOT; DOT; DOT; DOT;
	LETTER;
}
SEVEN() {
	DASH; DASH; DOT; DOT; DOT;
	LETTER;
}
EIGHT() {
	DASH; DASH; DASH; DOT; DOT;
	LETTER;
}
NINE() {
	DASH; DASH; DASH; DOT;
	LETTER;
}

eval $MESSAGE