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jobin-sun / raspberry-gpio-python

Automatically exported from code.google.com/p/raspberry-gpio-python
MIT License
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PWM support #4

Open GoogleCodeExporter opened 9 years ago

GoogleCodeExporter commented 9 years ago 
Add support for PWM

Original issue reported on code.google.com by btcros...@googlemail.com on 9 Sep 2012 at 3:14

GoogleCodeExporter commented 9 years ago 
Software PWM will be available in 0.5.2a

Original comment by btcros...@googlemail.com on 15 Mar 2013 at 10:47

GoogleCodeExporter commented 9 years ago 
Experimental software PWM now released in 0.5.2a
For documentation, see http://code.google.com/p/raspberry-gpio-python/wiki/PWM

Original comment by btcros...@googlemail.com on 26 Mar 2013 at 12:27

GoogleCodeExporter commented 9 years ago 
few suggestions :
- make frequency default to 50Hz (usual PWM frequency)
- give ability to set pulse up duration in µs
- give servo angle setter function : pulse in µs = 1520 + angle*400/45
   this is the futaba and most used standard : 1520µs neutral, 400µs/45° travel
   there is also 1500 + angle*500/45 but it's not correct for most servos.

you should also take a look on RPIO.PWM 
(http://www.raspberrypi.org/phpBB3/viewtopic.php?f=32&t=36670)
it uses DMA instead of thread, for a really better result, avoid flickering or 
need to increase thread priority.

Original comment by eric.p...@gmail.com on 31 Mar 2013 at 9:15

GoogleCodeExporter commented 9 years ago 
Aptitude says I have the latest version of RPi.GPIO v.0.5.2.a-1 installed, but 
I get an error trying to use GPIO.PWM() or GPIO.cleanup(). I tried to print 
GPIO.VERSION but got the same not present error. It is like none of those 
functions/methods are there. Any help to know what to try next?

Original comment by bruce...@gmail.com on 23 Apr 2013 at 3:28

GoogleCodeExporter commented 9 years ago 
I learned my own answer - but I'll post here what helped in case it can help 
someone else. 
Even tho Aptitude said I had the latest version of python-rpi.gpio, when I ran:
[pip freeze] it showed me the version was only 0.3 something.
so then I was able to run the following to upgrade to the latest:
[sudo pip install RPi.GPIO --upgrade]
now the newer functions work! :-) Thanks for your work on this module!

Original comment by bruce...@gmail.com on 23 Apr 2013 at 11:54