Month: December 2013

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Raspberry Pi – AirPiano

Wouldn’t it be cool if you could control your MIDI equipped digital piano from your iPhone?  Imagine a player piano capable of jukebox queuing up MIDI or Audio files and playing them in order.  That was my goal!  RPI to the rescue.

RaspiModelB

Required Ingredients:

  • Raspberry Pi – Model B, 512MB RAM, 16GB SD Card, Raspbian Linux, Apple 12W USB Power Adapter, USB WiFi Dongle
  • USB MIDI Digital Device (e.g. Yamaha Clavinova CLP-440 with USB MIDI port and RCA L+R Audio Inputs)
  • Software:  Apache HTTP Server, PHP, MySQL, (Nice to have:  Netatalk file server, Shairport AirPlay server)

Instructions:

My original thought was to turn the Yamaha speakers into a AirPlay device for our many iOS devices.  It’s nice to pipe in background tunes without having to hook up a device.  AirPlay is great way to do that but I didn’t want to spend $100+ to be able to do that.  The Raspberry Pi is more than capable of doing this. I found an extremely helpful blog post here:  http://www.raywenderlich.com/44918/raspberry-pi-airplay-tutorial

NOTE: Power is a big issue for the Raspberry Pi.  If you are using a WiFi dongle or any other USB device, I recommend making sure your power supply has enough kick to keep the RPI going.   I started out with a microUSB adapter that advertised 700mA but performance became very unstable, especially under load.  I switched to a 12W Apple adapter that I had handy and the problems disappeared.   The RPI FAQ recommends 1.2A (1200mA).

Setup for AirPiano – MIDI Control

The Project Code: https://github.com/jasonacox/raspberrypi

  • MySQL: Database ‘piano’ – see piano.sql file
  • Dequeue Service: Run the cron.sh script to have the RPI scan for new midi or wave files to play. Run it with:
bash -x cron.sh 0<&- 1>/dev/null 2>/dev/null &
  • Apache: Install apache http with mod_php and mysql support
  • Website Code: Install index.php, setup.php and the folder.png files into the document root of your webserver. Upload the MIDI (*.mid) and WAVE (*.wav) files to this location. Be sure to update $globalBase in setup.php to the folder where these files are located.

 

AirPlay via Raspberry Pi

Adam Burkepile has the best tutorial I’ve found on how to set up a RPI for AirPlay:

http://www.raywenderlich.com/44918/raspberry-pi-airplay-tutorial

Apple Share (AFP) Server via Raspberry Pi

The RPI is great for a tiny file server!  At the least, having it run an AFP server will allow quick drag and drop transfer from your Macs.  A Samba service for Windows shares is easy to set up as well.

sudo apt-get install netatalk

Yes, it is that easy.  Finder will now show your Raspberry Pi under “shared” along with any other local network shares:

Screen Shot 2013-12-27 at 11.22.08 PM