ECE497 Lab11 Using ALSA - Revision history

Yoder: Delete, there's a newer page out there.

2011-12-09T19:27:10Z

Delete, there's a newer page out there.

Yoder: /* Setup */ Added how to save settings.

2011-05-13T21:14:29Z

‎Setup: Added how to save settings.

Yoder: Added installing alsa libraries

2011-05-13T01:21:51Z

Added installing alsa libraries

Yoder: /* Setup */

2011-05-12T16:27:21Z

‎Setup

Yoder: /* Setup */ Adding more notes on how to setup.

2011-05-12T16:22:05Z

‎Setup: Adding more notes on how to setup.

Yoder: /* Lab 11/6 - Using ALSA */ Added link to ti wiki

2011-05-12T15:24:36Z

‎Lab 11/6 - Using ALSA: Added link to ti wiki

Yoder: Initial copy from the OSS lab

2011-05-12T15:22:33Z

Initial copy from the OSS lab

New page

[[Category:ECE497]]

Be sure you have done Lab 10 before this lab so all your software is set up.

== Lab 11/6 - Using ALSA ==

This is a placeholder...

== Problems and Solutions ==

=== Killing pulseaudio ===

Be sure to run:
<pre>
killall -9 pulseaudio
</pre>
before using ALSA.

=== Some notes on ALSA ===

I've gotten [http://www.suse.de/~mana/alsa090_howto.html#sect02 this] example working. I'm also looking [http://www.equalarea.com/paul/alsa-audio.html#playex here].

On the Beagle you need to:
<pre>
# opkg install alsa-dev
</pre>

On the host:
<pre>
$ sudo apt-get install libasound2-dev
</pre>
Go to the class dfs site and get <code>alsaWrite.c</code>. Compile it with
<pre>
# gcc -lasound alsaWrite.c
# ./a.out
</pre>
It runs on the Beagle and desktop and produces a sound.

It's shouldn't be hard to convert <code>alsaWrite.c</code> to <code>alsaRead.c</code>. See the sites above for hints.

← Older revision		Revision as of 19:27, 9 December 2011
Line 1:		Line 1:
−	[[Category:~~ECE497~~]]	+	[[Category:ToDelete]]
		+
		+	Use [[EBC Exercise 08 Using ALSA for Audio Processing]] instead.

	Be sure you have done Lab 10 before this lab so all your software is set up.		Be sure you have done Lab 10 before this lab so all your software is set up.

← Older revision		Revision as of 21:14, 13 May 2011
Line 74:		Line 74:

	Keeping DAC2 Analog up allows the output of the ALSA program to be heard.		Keeping DAC2 Analog up allows the output of the ALSA program to be heard.
		+
		+	You can save your setting for after the next reboot with:
		+	<pre>
		+	sudo alsactl store
		+	</pre>
		+	Details are [http://linux.dsplabs.com.au/alsamixer-and-alsactl-store-adjust-and-save-alsa-mixer-settings-p29/ here].

	=== Some notes on ALSA ===		=== Some notes on ALSA ===

← Older revision		Revision as of 01:21, 13 May 2011
Line 10:		Line 10:

	== Problems and Solutions ==		== Problems and Solutions ==
		+
		+	=== Installing alsa libraries for cross compiling ===
		+	I tried using Dr. Yoder's 12-May-2011 version of his ALSA code to
		+	cross-compile it and then send it to my Beagle (just to run on the
		+	ARM, not the DSP). I ran into a number of problems with the cross-compiling not finding header files and libraries, and this is how I
		+	had to fix it...
		+
		+	From [http://www.beagleboard.org/~arago/arago-deploy/ipk/armv7a/], download:
		+	<pre>
		+	alsa-dev_1.0.18-r0.1_armv7a.ipk
		+	libasound2_1.0.18-r0.1_armv7a.ipk
		+	alsa-lib-dev_1.0.18-r0.1_armv7a.ipk
		+	</pre>
		+	Then run:
		+	<pre>
		+	$ ar -p alsa-dev_1.0.18-r0.1_armv7a.ipk data.tar.gz \| tar -zx
		+	$ ar -p libasound2_1.0.18-r0.1_armv7a.ipk data.tar.gz \| tar -zx
		+	$ ar -p alsa-lib-dev_1.0.18-r0.1_armv7a.ipk data.tar.gz \| tar -zx
		+	</pre>
		+	This creates in the current directory a '''usr/include''' and '''usr/lib'''
		+	directory with the ALSA header files and libraries in them.
		+	I then copied these files into my armv7a cross-compiler toolchain.
		+	Specifically:
		+	* I copied the 'alsa' folder in '''usr/include''' to '''/home/carlsojs/toolchains/usr/local/angstrom/arm/lib/gcc/arm-angstrom-linux-gnueabi/4.3.3/include'''
		+	* and I copied '''usr/lib''' to '''/home/carlsojs/toolchains/usr/local/angstrom/arm/lib/gcc/arm-angstrom-linux-gnueabi/4.3.3/lib'''
		+	* Then in the Makefile, I changed the ARM_TOOLCHAIN_PREFIX and defined the ARM_TOOLCHAIN_PATH:
		+	<pre>
		+	ARM_TOOLCHAIN_PREFIX ?= arm-angstrom-linux-gnueabi-
		+	ARM_TOOLCHAIN_PATH ?= /home/carlsojs/toolchains/usr/local/angstrom/arm
		+	</pre>
		+	I then added the following argument to ARM_CFLAGS, which gives the
		+	compiler an additional location to look for header files:
		+	<pre>
		+	-I$(ARM_TOOLCHAIN_PATH)/lib/gcc/arm-angstrom-linux-gnueabi/4.3.3/include
		+	</pre>
		+	And I added the following argument immediately before '''-lasound''' in
		+	ARM_LDFLAGS, which gives the compiler an additional location to look
		+	for libraries:
		+	<pre>
		+	-L$(ARM_TOOLCHAIN_PATH)/lib/gcc/arm-angstrom-linux-gnueabi/4.3.3/lib
		+	</pre>
		+	My gpp_exec (ARM executable) then cross-compiled for me. When I
		+	copied it to my BeagleBoard, it ran (after I killed PulseAudio), but
		+	it did give me BufferUnderrun errors.
		+
		+	=== Installing alsa libraries for cross compiling (quick hack) ===
		+
		+	My solution to get the cross compile to work was a quick:
		+	<pre>
		+	$ cd ~/BeagleBoard/c6run_0_95_02_02_beagleboard/toolchains/usr/local/angstrom/arm/arm-angstrom-linux-gnueabi/usr/include
		+	$ ln -s /usr/include/alsa .
		+	</pre>
		+	I didn't change anything in the Makefile. However this might introduce some problems since it is using the same headers on the ARM as on the host computer. Mine appeared to work without buffer underruns.

	=== Setup ===		=== Setup ===

@@ Line 16: / Line 16: @@
 * Run <code>$ killall -9 pulseaudio</code> to stop pulseaudio.
-* Run <code>alsamixer</code> and turn up '''DAC Analog''' and turn down '''Left Dig''' and '''Right Dig'''.  Do this by using the right arrow key to move to the slider you want to adjust and use the up and down keys to adjust.
+* Run <code>alsamixer</code> and turn up '''DAC2 Analog''' and turn down '''Left Dig''' and '''Right Dig'''.  Do this by using the right arrow key to move to the slider you want to adjust and use the up and down keys to adjust.  It's a lot of right arrows before you see '''DAC2 Analog''';  I count 14. Don't stop at ''DAC Voice'' or ''DAC1 Analog''.  It's then another 20 to '''Left Dig'''.
 === Some notes on ALSA ===

← Older revision		Revision as of 15:24, 12 May 2011
Line 6:		Line 6:

	This is a placeholder...		This is a placeholder...
		+
		+	There are ALSA examples [http://processors.wiki.ti.com/index.php/OMAP%E2%84%A2/DaVinci%E2%84%A2_System_Integration_using_Linux_Workshop here] that are built on DMAI.

	== Problems and Solutions ==		== Problems and Solutions ==

@@ Line 11: / Line 11: @@
 == Problems and Solutions ==
-=== Killing pulseaudio ===
+=== Setup ===
-Be sure to run:
+There are a couple of things you need to after booting up before running the ALSA stuff.
-<pre>
-killall -9 pulseaudio
+* Run <code>$ killall -9 pulseaudio</code> to stop pulseaudio.
-</pre>
+* Run <code>alsamixer</code> and turn up '''DAC Analog''' and turn down '''Left Dig''' and '''Right Dig'''.  Do this by using the right arrow key to move to the slider you want to adjust and use the up and down keys to adjust.
-before using ALSA.
 === Some notes on ALSA ===