If you want to have a nice, long weekend project for the coming winter, Magic Morse may get you all keyed-up (no pun) for some short-day fun.
Magic Morse Decoder is a diverse project with elements of learning something new, mathematical algorithms, PICAXE implementation, PBASIC'ish coding, and lots of opportunity to be original in the construction and presentation of the overall project. Here is a YouTube link that covers the basics: http://www.instructables.com/id/Morse-Code-Magic-An-Algorithm/
The source code for the very inexpensive PICAXE 08M2 is available here (free registration is required before download): http://www.picaxeforum.co.uk/showthread.php?19123-Morse-Code-Decoding-8WPM-with-a-PICAXE-08M2
There is a PDF in the Instructables link above that can be downloaded that shows the 1 IC decoder schematic with minimal external requirements. A previously published 555 oscillator circuit is used so as not to reinvent the keyer: http://www.sentex.net/%7Emec1995/circ/morse1.htm
What is unique about this circuit is that almost every Morse Code PIC project relies on an external tone-decoder IC which may cost more than the PIC; however, Magic Morse is all software. The 08M2 code runs at 32MHz and the decoding hits a ceiling of about 10WPM (still not bad for a newbee that is just learning.) The code can be ported to a 64MHz PICAXE 20X2 (or a pre-programmed chip can be purchased inexpensively) if you are not into software porting. At the 64MHz processor clock, the 20X2 uC can decode straight-code up to or slightly above 15WPM or can exceed 25WPM if Farnsworth timing is included between characters.
Enjoy the Winter...
- Ray
Magic Morse Decoder is a diverse project with elements of learning something new, mathematical algorithms, PICAXE implementation, PBASIC'ish coding, and lots of opportunity to be original in the construction and presentation of the overall project. Here is a YouTube link that covers the basics: http://www.instructables.com/id/Morse-Code-Magic-An-Algorithm/
The source code for the very inexpensive PICAXE 08M2 is available here (free registration is required before download): http://www.picaxeforum.co.uk/showthread.php?19123-Morse-Code-Decoding-8WPM-with-a-PICAXE-08M2
There is a PDF in the Instructables link above that can be downloaded that shows the 1 IC decoder schematic with minimal external requirements. A previously published 555 oscillator circuit is used so as not to reinvent the keyer: http://www.sentex.net/%7Emec1995/circ/morse1.htm
What is unique about this circuit is that almost every Morse Code PIC project relies on an external tone-decoder IC which may cost more than the PIC; however, Magic Morse is all software. The 08M2 code runs at 32MHz and the decoding hits a ceiling of about 10WPM (still not bad for a newbee that is just learning.) The code can be ported to a 64MHz PICAXE 20X2 (or a pre-programmed chip can be purchased inexpensively) if you are not into software porting. At the 64MHz processor clock, the 20X2 uC can decode straight-code up to or slightly above 15WPM or can exceed 25WPM if Farnsworth timing is included between characters.
Note: Straight Morse Code uses a 3-dit timing interval (quiet period - no tone) between individual elements of a word and a 3-dit to 5-dit timing between words. Farnsworth encoding extends the between element times while maintaining an approximate 15WPM timing within each element of a character. This additional time allows the Magic Morse software time to output the decoded character to the LCD or PC at 9600 BAUD and "get back into the loop" for decoding the next character.
As shown in the YouTube video http://youtu.be/9kZOqdeUl2w the circuit can also decode ARRL audio files using a PC. Although I have not personally tried it, using a PC and a Software Defined Radio, SDR program the Magic Morse implementation should be able to decode real-time Morse Code.
Enjoy the Winter...
- Ray