That sketch is playing a tune making square waves of different
frequencies. That's not really the same as PWM, which varies the
length of the pulse, but the frequency stays constant. There are a
few ways to generate a square wave of a given freq. in Pd, if that is
your goal. If you want to do it by modeling the Arduino's use of a
timer to turn a signal on and off, that might be an interesting
exercise. One easier way, though, would be to amplify and clip a sine
wave.

[osc~ 440] | [*~ 50] | [clip~ -0.5 0.5]

then if you plug a 50 cent piezo buzzer into the sound card of your
$1000 laptop, it will sound just like a $3 avr!

Then you could store the note durations and frequencies in 2 separate
arrays, like in the Arduino sketch, where the freq is sent to the
[osc~] and the duration is sent to a [delay] that sends a bang to a
counter that increments to the next array elements. Then it will play
"Twinkle, twinkle," and what could be better than that!

Collin

Message: 6 Date: Sat, 07 Nov 2009 22:59:36 +0100 From: altern altern2@gmail.com Subject: [PD] arduino melody example in PD? To: the PureData - mailinglist pd-list@iem.at Message-ID: 4AF5EDC8.6040407@gmail.com Content-Type: text/plain; charset=ISO-8859-1; format=flowed

hi

i have been trying to port this example to PD

http://arduino.cc/en/Tutorial/Melody

it just uses a piezo to buzz a song. i dont understand very well this PWM controls and also I am finding quite difficult to translate the arduino code to PD. So after some headache i thought maybe someone has already done this for PD?

thanks

enrike