This is a little circuit I built for a greeting card. I won't go into a lot of detail here since I've described pretty much all of it in detail in this YouTube video of mine.

How does it work?

  1. You get some RTTTL ringtone of the net. In the archive none are included (there are just too many douchebags around the Internet going after Copyright violations that I'm not going to take my chances here). You will immediately find stuff if you google for "RTTTL ringtone [your song]".
  2. The RTTTL then is parsed with the Python "rtttl_parser" application included in the pacakge. It transforms the RTTTL input into a file that has frequencies/durations.
  3. The frequency/duration file can then either be simulated (unsing the "simulator" included). This will give you a WAV-file.
  4. Or you can convert it directly to code with the "codegenerator". The code can be included in the example and runs on the AVR ATtiny26 as-is.