@polonos13: I'm guessing you are using a Duemilanove or an Uno. These boards use the '328 chip. This means that you will only be able to have 3 tones declared at any time. You have two options: either get a board with a '1280 chip, or get a second '328 board. In the latter case, you'll have to communicate with the second controller the tones you want it to play. I can help you with that.
@marklar: Indeed. The timers will ONLY be used for Tone, though. This means that if you use all of the timers, you won't be able to use millis(), PWM, etc...
@Grumpy_Mike: The Tone library is pretty straightforward. One OCx output per timer (in CTC mode), so if the controller has 3 timers, 3 tones, and likewise for the '2560 with 6 timers, 6 tones.
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