Morse Code Encoder with Microcontroller

The morse code encoder is an electronic device that is used to set the text message to code format. Most commonly used encoders in digital electronics. The below image contains the complete schematic diagram of the morse coder device. The aim of this circuit is to convert the text to morse code based on programming. This circuit is developed by using a microcontroller of PIC16f family is operates with 20 MHz crystal to provide higher speed operations. The PS/2 keyboard is an analogue keyboard used as an input device. The buzzer is used to indicate the key is pressed on the keyboard.

If any key is pressed on the keyboard, then clock pulses will be generated to each data bit. We can read a data bit when the clock goes from “1” to “0” (falling edge of the clock). 11 data bits will form a word which is considered as ASCII value that has 1 start bit, 8 data bits, 1 parity bit and 1 stop bit. If this ASCII value is given to the microcontroller, then the microcontroller generates the morse code of particular ASCII value using the program. Thus, this morse code encoder takes text inputs and it turns into dots and dashes.

Translate keyboard Codes to ASCII Characters

The ASCII stands for “American Standard Code for Information Interexchange” that is a type of code for data transmission. In embedded system the data will be stored in digital form. There is no way to store characters directly. Each character has its digital code equivalent is called ASCII code. The key code array contains all keyboard codes that can be recognized by the program. There we find the ASCII code of character D is 0x23.

Translate ASCII Characters to Morse Code

Their PIC microcontroller also needs to translate among ASCII characters and Morse code in this above circuit. Here to follow the method for translate the ASCII character to morse code that describe the program will search the position of the desired character and look for the corresponding Morse code.

The morse code contains: a dot (.) or a dash (-) which is used to define the text messages. This is good because we can use the binary format to represent such code. A dot will be represented by the binary “0” while a dash is represented by the binary “1”.The Morse code for our letter D is ‘-..’ (1 dash followed by two dots). We need three bits to represent this number.
Most Morse characters only contain up to 5 marks (dots or dashes). We need 5 bits to represent such character. The PIC microcontroller has eight bits are reserved for each character, therefore we have unused bits 3. We used these to encode the length of each character. The following image shows the binary Morse data for the letter D (hexadecimal 0x61).

The bits 5-7 are used to indicate the length of the Morse character: the binary 011 (decimal number 3). They indicate that our morse character contains 3 marks: bits 1,2 and 0.

Morse Code Program

Here provide a simple morse code program by using embedded C programming language with a switch statement. If you enter any character is given in the program to generate the respective morse code.

#include<stdio.h>
#include<conio.h>
#include<string.h>
#include<process.h>

void main()
{
char str1[25],str2[100];
clrscr();
fflush(stdin); //clear the input buffer//
printf(“enter the String”);
gets(str);

int j=0;
for(int i=0;i<=strlen(str1);++)
{
switch(toupper(str[i]))
{
case ‘A’:
str2[j++]=’.’;
str2[j]=’.’;
break;

case ‘b’:
str2[j++]=’.’;
str2[j++]=’.’;
str2[j++]=’.’;
str2[j]=’.’;
break;

case ‘c’:
str2[j++]=’.’;
str2[j++]=’.’;
str2[j++]=’.’;
str2[j]=’.’;
break;

case ‘D’:
str2[j++]=’.’;
str2[j++]=’.’;
str2[j]=’.’;
break;

case ‘E’:
str2[j]=’.’;
break;

case ‘F’:
str2[j++]=’.’;
str2[j++]=’.’;
str2[j++]=’.’;
str2[j]=’.’;
break;

}

Applications of Morse Code

Aviation:  The Morse code is still used in today’s aviation field. Before days, they are used to maintain communication between planes or flights and also in ATC (Air Traffic Control). Nowadays, they are used for giving navigation helps to the pilots and ensure that the stations, where all stations names transmit a short set of identification letters (usually a two-to-five-letter version of the station name) in morse code.

Radio: Morse code encoder is still used in the communication system. As mainly used by radio operators to communicate with each others. At most of the radio amateur uses this Morse code to transmit radio.

Navy: The navy people also communicate with other ships with morse code for secrecy purpose. They will send an anguish signal or help to others ship when they are in need. In Titanic movie, you can observe that some people click one pointer to send text that is a morse code signal. Navy people will signal the other ship using the lights by switching ON and OFF in a morse code form that sequence of ON and OFF of light is also in Morse code.

Normal Applications: Morse code encoder is still used by some people to send the suffering signals, it is extensively used in military application and many of use in aviation submarines even by Government applications.

Even though there are difference types of code communications, such as binary code communication, analogue code communication but morse code is one of the important communication technologies in the  radio communication. The information which is given in this article will be helpful to the viewers. Furthermore, any queries, suggestions or power electronics projects, you can comment us by commenting in the comment section below.