WB7FHC's Morse Code Decoder v. 1.1 (c) 2014, Budd Churchward - WB7FHC This is an Open Source Project http://opensource.org/licenses/MIT
Search YouTube for 'WB7FHC' to see several videos of this project as it was developed.
MIT license, all text above must be included in any redistribution
This project makes use a custom built tone decoder module using the LM567C microchip. Details of this module will eventually be posted on line. This module allows you to tune to the frequency of a specific tone while ignoring noice and other tones of different frequencies
The program will automatically adjust to the speed of code that is being sent. The first few characters may come out wrong while it homes in on the speed. If you are not seeing solid copy, press the restart button on your Arduino. You can try adjusting the tone decoder. Lowering the volume of the incoming CW can also help. If the tone decoder is not centered on the frequency of the incomming signal, you may have to fine tune the module as you lower the volume.
The software tracks the speed of the sender's dahs to make its adjustments. The more dahs you send at the beginning the sooner it locks into solid copy.
After a reset, the following text is very difficult to lock in on:
SHE IS HIS SISTER because there are only two dahs in the whole
phrase and they come near the end. However, if you reset and then
send CALL ME WOODY it will match your speed quite quickly.
This project is built around the 20x4 LCD display. The sketch includes funtions for word wrap and scrolling. If a word extends beyond the 20 column line, it will drop down to the next line. When the bottom line is filled, all lines will scroll up one row and new text will continue to appear at the bottom.
This version makes use of the 4 digit parallel method of driving the display.
If you are planning on using a 16x2 you will want to make some changes. Frankly, I don't think scrolling makes sense with only two lines. Sometimes long words or missed spaces will result in only two words left on your display. If you don't have a 20x4 (they're really only a few bucks more) you might want to leave out the word wrap and scrolling.
Hook up your LCD panel to the Arduino using these pins:
LCD pin 1 to GND
LCD pin 2 to +5V
LCD pin 4 to D7
LCD pin 6 to D6
LCD pin 11 to D5
LCD pin 12 to D4
LCD pin 13 to D3
LCD pin 14 to D2
LCD pin 15 to +5V
LCD pin 16 to GND
Data from pin 8 of the LM567C will be fed to D8 on the Arduino When this pin is HIGH there is no tone detected. When this pin is LOW a tone of the set frequency has been detected.