Difference between revisions of "ECE497 Lab11 Using the Open Sound System (OSS)"
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You will still need the symbolic link from part 5, and make sure to update the file paths. | You will still need the symbolic link from part 5, and make sure to update the file paths. | ||
+ | |||
+ | == Problems and Solutions == | ||
+ | I find that running | ||
+ | <pre> | ||
+ | cat /dev/dsp > /dev/dsp | ||
+ | </pre> | ||
+ | |||
+ | gave me this error: | ||
+ | <pre> | ||
+ | -sh: can't create /dev/dsp: Device or resource busy | ||
+ | </pre> | ||
+ | |||
+ | This did not seem to cause problems until part b of the lab. I found [http://linux.dsplabs.com.au/lsof-grep-snd-how-to-free-a-linux-sound-device-p25/ this website] to solve my problem. Apparently, the problem is that pulseaudio is using /dev/dsp, and refuses to give it up. When I killed pulseaudio (the rude way, not the graceful way), then running cat /dev/dsp > /dev/dsp worked, and my executable worked. I don't know what killing pulseaudio does to the system, I haven't noticed any ill-effects yet... |
Revision as of 13:47, 27 April 2011
Be sure you have done Lab 10 before this lab so all your software is set up.
Lab 11/6 - Using the OSS Driver
Lab 11 is Lab 6 is on pages 171-186 of DaVinci-OMAP_Workshop_v2.0.pdf. In doing this lab you will get audio from the line-in jack on the Beagle and sent it out the speaker jack.
- Go to the class dfs site and get:
- setpaths.mak
- setpaths.sh
- Move the setpaths files in the workshop directory to another location.
host $ cd workshop host $ mv setpaths.sh setpaths.sh.orig host $ mv setpaths.mak setpaths.mak.orig
- Copy the setpaths files you got from DFS into the workshop directory. In Lab 11/6 you will edit these files so they are correct.
You will still need the symbolic link from part 5, and make sure to update the file paths.
Problems and Solutions
I find that running
cat /dev/dsp > /dev/dsp
gave me this error:
-sh: can't create /dev/dsp: Device or resource busy
This did not seem to cause problems until part b of the lab. I found this website to solve my problem. Apparently, the problem is that pulseaudio is using /dev/dsp, and refuses to give it up. When I killed pulseaudio (the rude way, not the graceful way), then running cat /dev/dsp > /dev/dsp worked, and my executable worked. I don't know what killing pulseaudio does to the system, I haven't noticed any ill-effects yet...