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OSSIE-SCA on the Gumstix Overo

The Gumstix Overo is an OMAP3 based system similar to the Beagle Board. The primary difference between the two products is that the Overo exposes more pins to the user.

OSSIE-SCA runs on the Beagle Board (as seen is this video). Since all the build information is created using OpenEmbedded it is easy to repeat this work on the Overo.

The procedure to build this waveform for the Overo is :

  1. Install the Overo build environment. The builds the omap3-console-image.
  2. Copy the kernel and file system to a micro-SD card per instructions on the gumstix website.
  3. Next, install the ossie collection of OpenEmbedded recipes into the Overo build environment. Installation is simplified by Gumstix providing the user.collection area. This reduces the number of variables that must be configured properly. In overo-oe run:
    $ svn co https://svn.geekisp.com/opensdr/OE/ossie_collection user.collection
  4. Add these lines to your build/conf/local.conf file: 
    IMAGE_EXTRA_INSTALL = "screen ossie-fm-from-file"
require conf/distro/include/sane-ossie-revs.inc
  5. Get an account on the OSSIE subversion system. (I really should remove the recipes that need this ...) See http://ossie.wireless.vt.edu/trac/wiki/Downloads on creating an account and getting svn access. The openSDR subversion repository does not require an account for read-only access.
  6. Run the following commands. This makes sure you have cached login information and accepted ssh host id's. This prevents the automated build from hanging while waiting for answer to the prompts.
    $ svn ls https://trac.geekisp.com/opensdr
$ svn ls https://ossie.wireless.vt.edu/repos/ossie
  7. Run: 
    $ bitbake -c clean task-base
$ bitbake omap3-console-image

    If this fails looking for pulse.h try:

    $ bitbake pulseaudio-meta
$ bitbake omap3-console-image

    I think there is a dependency problem that trips up multi-threaded builds.

  8. Flash the new image onto the micro-SD card.
  9. Copy the data file on to the micro-SD card:
    $ cd /sdr
$ wget http://ossie.wireless.vt.edu/~balister/capture/npr_iq_sample.dat
  10. Set the default sample rate for pulseaudio by changing the line in /etc/pulse/daemon.conf from 
    ; default-sample-rate = 44100

    to

    default-sample-rate = 48000

At this point you should have a micro-SD card for the Overo that boots and has OSSIE-SCA installed, and there is a FM demod waveform ready to run.

Now, we must get all this running. Attach some speakers to the Overo, boot it an dlog in via the serial port. (or screen if you have that set up). I use screen to simulate having several consoles. The start screen use:

screen -S sca

If you are using minicom, remap the control key sequence from Ctrl-a to Ctrl-b. In screen, Ctrl-a c creates a new session, Ctrl-a n advance to the next session (in a circular fashion), and Crtl-a d disconnects from screen session. To reconnect use:

screen -r sca

Man screen has lots more information.

OK, lets run the waveform

  1. start screen and run omniNames -start.
  2. Create a new session (Ctrl-a c) and run pulseadio.
  3. Create a new session and run nodeBooter -D -d /nodes/GPP-sound-node.dcd.xml.
  4. Create a new session and run c_wavLoader.
  5. Have c_wavLoader load the waveform and start it, you should hear a message from an NPR sponsor.

    If you have any trouble, or have suggestions for improving this page, drop me an email.

  • By balister at 12/14/2008 - 20:37