Hey, just thought I shared a simple Use I found with a pi.
For the needs of a musical performance, I use a small usb midi keyboard (LPK 25http://www.akaipro.com/lpk25) that I carry around as a kind of remote to trigger events (and also as a basic keyboard) during shows. Until now I use long usb cables that are annoying and get in the way of everything else set up. I thought about midi wireless solution like these
http://www.musiciansfriend.com/keyboard ... -interface
but the small keyboard I use is usb only so I need some kind of computer (plus these solutions are really expensive).
then I had a raspberry lying around, with a wifi dongle, and the keyboard is class-compliant, so I thought I'd use this to remotely control my software (ableton live). Which gives me a very compact wireless midi keyboard, something impossible to find in this format (much smaller than the midair which isn't made anymore).
Basically what I needed to do was:
-setup the wifi dongle as an ad-hoc network and adding lines to /etc/rc.local for it to create a network at boot
-install pure-data extended
-write a small pd patch that uses the keyboard as an input, and send it through OSC/udp on the wifi network, to the target computer
-on the target computer write a max/msp (yes that's what I usually use) patch that gets incoming messages from OSC/wifi and send them to ableton live using a virtual midi cable (also doable with max for live but it's easier this way)
-add a line to etc/rc.local opening this pd patch at boot (with the appropriate startup parameters to activate the midi, deactivate the sound and the GUI inside pd)
-inside the pd patch, I also added this: if you type a certain key three times in a short time, it will trigger the pi to shutdown. figured it would be better than just unplugging it (but is it really necessary?). For that I found out that pd can send direct bash commands.
-and of course I added a small usb battery to power everything so I have something portable. For now I use adhesives (I still need to find out if the battery will last long enough and if it's 100% reliable, and a way to fix everything together for it to be practical to carry, but still temporary)
When I need to use it I just plug the battery, wait for the network to appear on my laptop, connect to it, start max/msp and ableton live, then I can use my keyboard remotely, plus there is no apparent latency (which was my fear), so here it is..
I realise this explanation is a bit dry/abstract, and lacks precisions, but If anyone is interested I can develop, and also show you what I use it for...
It's basically a musical show with tiny everyday objects that solenoids hits.
(one example here, no it has nothing to do with the pi)
http://www.dailymotion.com/video/xil9oj ... an-2_music
My first idea with the Pi was to make a very portable version of what's shown in the video to use outdoor,so use the Pi as a simple midi/audio player with pd. The midi sequence would triggers solenoids hooked up to an arduino through transistors (didn't find a way to command the arduino GPIO with pure data, and had already an arduino with everything soledered and set up to it). I have this working, except for the power supply part (I just need a 12V battery with enough power for the solenid, a charger, and a 12V to 5V converter for the pi and arduino), and a favorable interesting outdoor context (probably urban, since it works better with metallic sounds).
ok enough talking now, tell me if you're interested by either of these projets, if you'd like details, or if you're bored to death. just thought I shared.