On May 25, 2006, at 2:59 PM, Frank Barknecht wrote:
Hallo, Hans-Christoph Steiner hat gesagt: // Hans-Christoph Steiner wrote:
On May 25, 2006, at 12:22 PM, Frank Barknecht wrote:
There also is a PWM in the docs, which doesn't need any externals:
I should mention then that these objects are written in Pd, and only rely on some purepd objects, which are also written in Pd.
Except one external from zexy. ;)
3.audio.examples/K01.pulse.width.mod.pd
Unfortunately, this patch is missing from CVS, so it doesn't make it into Pd-extended. But in any case, this is the PWM knowledge wrapped up into a easy to use form.
Sorry, I think it's called 3.audio.examples/J03.pulse.width.mod.pd now, but for years it was called 3.audio.examples/ 22.pulse.width.mod.pd and for some time 3.audio.examples/E05.pulse.width.mod.pd as well. ;)
It's just substracting two [phasor~]'s with slightly different frequencies, which is equivalent to PWM.
Ah yes, [pwm~] is using zexy's [>~]. I was looking at [pwm]. That
example (I am looking at K01.pulse.width.mod.pd from 0.38.4) is very
simple, but as it is, it is not usable. Notice how the LOW and HIGH
change values. PWM needs be 0 for LOW and 1 for HIGH. That example
is usable in an audio context, since DC offset doesn't really
matter. I guess you could rely on the DAC in the soundcard to remove
the DC, but that is probably asking for trouble.
I am open to suggestions for a different algorithm. Or perhaps
someone should write [>~] in Pd.
.hc
Man has survived hitherto because he was too ignorant to know how to
realize his wishes.
Now that he can realize them, he must either change them, or perish.
-William Carlos
Williams