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Author Topic: Analog CV output?  (Read 725 times)
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Hello,

can I use the Arduino to output control voltage that is used in modular synthesizers?
I created a analog style Midi sequencer and would like to add CV output, i still have some PWM Ports free on my Arduinio Mega.


thnx a lot
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Sure you can, there are many ways to do this.

The simplest way would be to use a lowpass filter on one of your PWM outputs.  You could also do other types of DACs, like an R2R resistor ladder.  You could also use a digital pot chip, and use each pot as a voltage divider.

I'd suggest the PWM option, because of its simplicity, but you could try different things.
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mmh, i dont really got your answer, i would like to send a CV, which is usually a current from 0-8V if i remeber correct to be sent instead
of this midi playnote: 

 noteOn(channel2[stepnr], note[stepnr], 0x7F);  //play note+

how would i line for CV out look?


Im not really into the whole IC/electrical stuff, do
you mean that when I connect a lowpasss filter i can adjust the voltage?
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Quote
Im not really into the whole IC/electrical stuff, do
you mean that when I connect a lowpasss filter i can adjust the voltage?

Then you can't do it. It is not just software you need but so e hardware as well.
If you connect a low pass filter to a PWM pin you will get a DC voltage depending on the analogue output you write. But you need some amplifiers after the filter to get the voltage right.

See:-
http://www.thebox.myzen.co.uk/Tutorial/PWM.html
« Last Edit: November 13, 2011, 05:02:12 am by Grumpy_Mike » Logged

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