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@madc
Last active Dec 17, 2019
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Simple morse en- & decoding for Arduino (including LED Example)Build after the specs on http://en.wikipedia.org/wiki/Morse_code
Copyright (c) 2015 Matthias Esterl
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
//Define the LED Pin
#define PIN_OUT 9
//Define unit length in ms
#define UNIT_LENGTH 250
//Build a struct with the morse code mapping
static const struct {const char letter, *code;} MorseMap[] =
{
{ 'A', ".-" },
{ 'B', "-..." },
{ 'C', "-.-." },
{ 'D', "-.." },
{ 'E', "." },
{ 'F', "..-." },
{ 'G', "--." },
{ 'H', "...." },
{ 'I', ".." },
{ 'J', ".---" },
{ 'K', ".-.-" },
{ 'L', ".-.." },
{ 'M', "--" },
{ 'N', "-." },
{ 'O', "---" },
{ 'P', ".--." },
{ 'Q', "--.-" },
{ 'R', ".-." },
{ 'S', "..." },
{ 'T', "-" },
{ 'U', "..-" },
{ 'V', "...-" },
{ 'W', ".--" },
{ 'X', "-..-" },
{ 'Y', "-.--" },
{ 'Z', "--.." },
{ ' ', " " }, //Gap between word, seven units
{ '1', ".----" },
{ '2', "..---" },
{ '3', "...--" },
{ '4', "....-" },
{ '5', "....." },
{ '6', "-...." },
{ '7', "--..." },
{ '8', "---.." },
{ '9', "----." },
{ '0', "-----" },
{ '.', "·–·–·–" },
{ ',', "--..--" },
{ '?', "..--.." },
{ '!', "-.-.--" },
{ ':', "---..." },
{ ';', "-.-.-." },
{ '(', "-.--." },
{ ')', "-.--.-" },
{ '"', ".-..-." },
{ '@', ".--.-." },
{ '&', ".-..." },
};
void setup()
{
pinMode( PIN_OUT, OUTPUT );
digitalWrite( PIN_OUT, LOW );
}
void loop()
{
String morseWord = encode( "SOS " );
for(int i=0; i<=morseWord.length(); i++)
{
switch( morseWord[i] )
{
case '.': //dit
digitalWrite( PIN_OUT, HIGH );
delay( UNIT_LENGTH );
digitalWrite( PIN_OUT, LOW );
delay( UNIT_LENGTH );
break;
case '-': //dah
digitalWrite( PIN_OUT, HIGH );
delay( UNIT_LENGTH*3 );
digitalWrite( PIN_OUT, LOW );
delay( UNIT_LENGTH );
break;
case ' ': //gap
delay( UNIT_LENGTH );
}
}
}
String encode(const char *string)
{
size_t i, j;
String morseWord = "";
for( i = 0; string[i]; ++i )
{
for( j = 0; j < sizeof MorseMap / sizeof *MorseMap; ++j )
{
if( toupper(string[i]) == MorseMap[j].letter )
{
morseWord += MorseMap[j].code;
break;
}
}
morseWord += " "; //Add tailing space to seperate the chars
}
return morseWord;
}
String decode(String morse)
{
String msg = "";
int lastPos = 0;
int pos = morse.indexOf(' ');
while( lastPos <= morse.lastIndexOf(' ') )
{
for( int i = 0; i < sizeof MorseMap / sizeof *MorseMap; ++i )
{
if( morse.substring(lastPos, pos) == MorseMap[i].code )
{
msg += MorseMap[i].letter;
}
}
lastPos = pos+1;
pos = morse.indexOf(' ', lastPos);
// Handle white-spaces between words (7 spaces)
while( morse[lastPos] == ' ' && morse[pos+1] == ' ' )
{
pos ++;
}
}
return msg;
}
@kristianlm

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@kristianlm kristianlm commented Oct 23, 2016

I believe your K is wrong: it should be -.- (see wikipedia)

@hypercyclicity

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@hypercyclicity hypercyclicity commented Feb 16, 2017

The encoding for the period character { '.', "·–·–·–" } uses different dots and dashes than the other encodings.

@tonytozoo

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@tonytozoo tonytozoo commented Feb 16, 2017

What if I want to translate 2400 characters, I've try in many different ways but none of them it works.
It works until 1000, any Idea why and how to solve this?

@ai8n

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@ai8n ai8n commented Jan 25, 2018

Newbie comment: Could you add more comments to this code? Ignorant minds want to know. :)

@pharrisuk

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@pharrisuk pharrisuk commented Feb 17, 2018

@a18n: One thing you might want to understand, as a newbie, is that, he's building (declaring, and initialising) an array of structures at the top, not just a struct as the comment implies.

@azcharlie2009

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@azcharlie2009 azcharlie2009 commented Mar 31, 2018

Does this work? I loaded it into my Teensy 3.6 and it does nothing.

@azcharlie2009

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@azcharlie2009 azcharlie2009 commented Mar 31, 2018

Sorry, my mistake. Needed to change PIN_OUT to 13 on Teensy

@ghost

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@ghost ghost commented Apr 9, 2018

Does anyone have the schematics for it?

@Erhannis

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@Erhannis Erhannis commented Jun 6, 2018

Most everything here appears to be compliant with the spec described on Wikipedia. However, I believe to get "The letters of a word are separated by a space equal to three dots (one dash)", it should be morseWord += " "; //Add tailing space to seperate the chars, with two spaces.

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@Erhannis Erhannis commented Jun 6, 2018

I fixed the mentioned bugs, including (in my tests) the out-of-memory bug I think @tonytozoo was having.
https://gist.github.com/Erhannis/17de678c9b6ac4d75ffa585156f513b8
I also added another space between chars, for spec compliance. (Should be three dots worth of space between chars, rather than two.)

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@mlh1407 mlh1407 commented Jun 17, 2018

will this code auto detect the users speed - im doing a project with kids and we have som trouble with the fact that kids morse with different speed -

@Jonas-N-Jacobsen

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@Jonas-N-Jacobsen Jonas-N-Jacobsen commented Dec 17, 2019

Super Newbie question:
I'm trying to get the morse code to work with an LED strip instead of the tiny LED on the Arduino. I want all of the LEDs on the strip to blink the morsecode simultaneously. But so far I can't get it to work.
I've added:

 **#include <FastLED.h>

 #define NUM_LEDS 300
 #define DATA_PIN 12
 CRGB leds[NUM_LEDS];**

and replaced pinMode(2, OUTPUT); with FastLED.addLeds<WS2811, DATA_PIN>(leds,NUM_LEDS);

But this does nothing. Any suggestions would be greatly appreciated!

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