PWM on more than 4 pins?

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ghostma...@gmail.com

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Mar 2, 2014, 2:24:31 PM3/2/14
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very time I try to use certain PWM pins on the BeagleBone Black I get this error for most of the pins (from the ones shown in yellow here: http://beagleboard.org/static/images/cape-headers-pwm.png)
I am using Ubuntu on my BeagleBone Black.
"RuntimeError: You must start() the PWM channel first"

Any reason why? What's the max number of same-frequency PWM channels I can have ongoing at any one time?

ghostma...@gmail.com

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Mar 2, 2014, 7:48:27 PM3/2/14
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just to add on to it, even with Angstrom, I can't seem to get more than 4 outputs for PWM. I only need 5..

Andrew Dai

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Mar 3, 2014, 10:14:20 AM3/3/14
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Which pins are you using?
P9_14
P9_22
P8_12
and P8_14 work just fine for me

Andrew Dai

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Mar 3, 2014, 10:16:27 AM3/3/14
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Woops sorry, my mistake.
I have PWM on P9_14 and P9_22


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ghostma...@gmail.com

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Mar 3, 2014, 4:10:18 PM3/3/14
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Firstly, the working pins tend to change randomly... Cos P8_13 works for me. Secondly yeah, I do get a set of 4 working PWMs but I need more than that, I need 5 pwm. I am trying to work with the Adafruit library but that gives me this error when I try it on some of them. Even the pyBBIO library doesn't support pwm outputs with the 3.8 kernel.

At this point I think that a stable version of the 3.2 Angstrom distribution will fit my needs as it is much easier to set the pin muxes. Does anyone know where to get them?
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