Question

Using Arduino to blink an LED in morse code.

Morse code is used as one of the methods for communications. It consists of a series of “dit” and “dah” symbols. (i) Develop an Arduino program to produce a Morse code to express the phrase “We are students” using Pin #13 (connect an LED that is in series with a 220-Ω resistor to Pins #13 to view the information sent via the Morse code). Express one “dit” with LED on for 0.3 seconds and then off for 0.3 seconds; express one “dah” with LED on for 0.9 seconds and then off for 0.3 seconds; express the space between letters with LED off for 0.9 seconds; and express the space between words with LED off for 2.1 seconds.

Answer 1

Please up vote ,comment if any query . Thanks for question .Be safe .

Note : check attached image for simulation schematic . Code compiled in arduino ide . simulation tested in proteus VSM.

Program Plan :

1. Create a string of morse code of "We are students . " , we can find morse code of equivalent char .
2. and create a four function one for dit ,dah ,and char space and word space .
3. dit() blink led for 0.3 seconds
4. dah turn on led for 0.9 seconds and off for 0.3 seconds
5. char space 0.9 seconds turn off led.
6. word space 2.1 seconds .
7. in arduino we have delay function takes mili seconds . 1 seconds =1000 mili seconds . delay(900) = 0.9 seconds.
8. set LED pin 13 as output .
9. set high and low led inside function .
10. / use for space between words . and space char used for space between chars .

Program :

#define morseLed 13 //define led pin 13 PB5
String phrase="We are students"; //string of we are students
String morsePhrase=".-- . / .- .-. . / ... - ..- -.. . -. - ..."; //morse code

void setup() {
pinMode(morseLed,OUTPUT); //led pin set OUTPUT DDRB|=(1<<PB5)
//DDRB|=(1<<PB5);
delay(100);

}

void loop() {
//run a loop from 0 index to till length of string moresephrase
for(int i=0;i<morsePhrase.length();i++)
{
if(morsePhrase[i]=='.') //if char is dit call dit message
dit();
else if(morsePhrase[i]=='-') //if char is dah call dah message
dah();
else if(morsePhrase[i]==' ') //if char space call charSpace message
charSpace();
else if(morsePhrase[i]=='/') //if char is / call wordspace message
wordSpace();
}

delay(5000); //each iteration 5 seconds delay

}

void charSpace()
{
digitalWrite(morseLed,LOW); //set low on led
//PORTB&=~(1<<PB5);
delay(900);
}

void wordSpace()
{
  
digitalWrite(morseLed,LOW);
//PORTB&=~(1<<PB5);
delay(2100);
}

void dit()
{
digitalWrite(morseLed,HIGH);
//PORTB|=(1<<PB5);
delay(300);
digitalWrite(morseLed,LOW);
//PORTB&=~(1<<PB5);
delay(300);
}

void dah()
{
digitalWrite(morseLed,HIGH);
//PORTB|=(1<<PB5);
delay(900);
digitalWrite(morseLed,LOW);
//PORTB&=~(1<<PB5);
delay(300);
}

Schematic :

Please up vote ,comment if any query .