Passive MIDI foot switch

posted Jan 20th 2009 11:21am by Caleb Kraft
filed under: classic hacks, digital audio hacks

foot

[Matt] was looking into some software that allows him to use his audio card as a means to control analog audio devices. After seeing how it worked, he got an idea to try to do the opposite. He is sending a signal into his audio input, and piping it to a pice of MIDI software. The input he has chose is a foot switch. To create the signal, he simply needed to supply voltage while the switch was depressed. You can see above that he used a battery and a simple contact switch to send the signal. He then piped it to a virtual MIDI port using Maple Virtual MIDI Cable. Unfortunately, this isn’t suitable for knobs, but that may be next on his list.

Comments [12]

tagged: foot switch, midi

12 Responses to Passive MIDI foot switch

hogiewan says:

January 20, 2009 at 12:01 pm

How is this passive?

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Abbott says:

January 20, 2009 at 12:16 pm

Hmm… that is a good question – passive usually means that a voltage isn’t sent from a device.

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Matt says:

January 20, 2009 at 1:02 pm

@hogiewan:

Author here, I described the switch as “passive” because that’s how it started out and the hardware was pretty much trivial. But you’re right, I should have just described it as a “Simple MIDI footswitch” or something. Mea culpa.

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Jay says:

January 20, 2009 at 3:01 pm

I’m suprised there isn’t even a resistor in series…. Current limiting devices are your Friend!

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tony says:

January 20, 2009 at 3:07 pm

haha, right on jay. And always isolate mains power. You wouldn’t want to let the magic smoke out.

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lame hack says:

January 20, 2009 at 5:53 pm

Honestly this is a pretty lame hack. 2 x 16bit 44khz for a binary signal activated by his foot. That’s a lot of redundant data and processing. It would be easier to pull apart an old mouse or keyboard and use glovepie.

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SOOPERGOOMAN187 says:

January 20, 2009 at 6:35 pm

I’m at a total loss with midi. been trying to set up for glovepie and can’t figure it out. Maybe the OP would be willing to help. Then maybe I could build this also and put it to good use.

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fartface says:

January 21, 2009 at 5:59 am

This would have been easier with the lpt port, yes your pc without one still has one, look for the header inside.

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Anonymous says:

January 21, 2009 at 6:33 am

I’m quite a noob so I’m missing the point of this.
what is this supposed to do? control some software application function via an analog switch connected to the midi port? emulate a keystroke?

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Liam says:

January 22, 2009 at 5:21 am

@anonymous: you’re not the only one. So, what does it actually do?

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Brother_Maynard says:

January 22, 2009 at 6:49 am

Orrr… You could just go the sysex route. Really not sure how this hack is totally useful. Although releasing a fake audio program with a fake soundbank and then having a website with a midi file that is linked to that app and let the drive-by malware begin. Anyhoo, keep plugging away.

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d clark says:

September 4, 2009 at 10:28 am

I’m looking at the miduino card by tom scarff http://tomscarff.110mb.co/products_prices.htmmiduino
to get input that can start/pause/continue a song using the song position indicator. we’ve bumped into a problem with not having an external clock in external sync mode. this sort of relates to the foot pedal. Any suggestions? I need to have a bunch of these up and running before halloween!

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