Midi CV / Gate with Phidgets Analog Out 4?

[stahlblau]

Hi,

i'm wondering if it is possible to do a midi cv/gate interface with the "1002_0 - PhidgetAnalog 4-Output". I.E something like flowstone adsr to control voltage...

Is there someone who is thinking about any way to do a midi cv/gate thing with flowstone and external hardware?

Please let me know

all the best
André

[stahlblau]

Nobody?

[fixstuff555]

Ok I'll bite. I don't know much about what you are looking for, however I did find this info:

http://obsoletetechnology.wordpress.com/projects/midi-cvgate-converter/

If this the functionality you are looking for, I would say that the answer is yes. The MIDI functionality is pretty functional in Flowstone, as well as the Phidget module you are looking at. I have interfaced both my MIDI keyboard, and parsed out the MIDI messages just to check it out - it worked as advertised. As to the conversion of the MIDI message to the Control Voltage, this shouldn't be an issue, but I have found that there are some things that aren't quite working right yet with Flowstone 2. If I were you, when you start playing around with this, is use the Flowstone 1.1.5 version for a bit.

As far as the mechanics of the flowstone code, it should be fairly straightforward. A note is a dec value of 21-108 per this:

http://upload.wikimedia.org/wikipedia/commons/7/7a/NoteNamesFrequenciesAndMidiNumbers.svg

and the CV voltages should be either Volts per Octave or Hertz per volt (like this)
http://en.wikipedia.org/wiki/CV/Gate

Both of these should be possible to scale to the voltage output of the Phidget by either a lookup table or a bit of math. I might be able to help out a bit more, if you let me know what you want to do in more detail, but I think all of the hardware pieces you are looking at should be possible.

As to the electrical requirements, you should be able to drive the MIDI input directly from the Phidget, but for enhanced equipment durability, I would buffer the output with a non-inverting buffer of some sort to protect your $90 phidget module. The LM358 circuit used in the first link should be adequate to protect your Phidget. You will also need a digital output for the Gate Control, since the 1002 Phidget only has analog out.

Hope this helps..