Thread:CircuitCo talk:Audio Cape RevB/Audio Cape instructions

These instructions got the audio cape working for me using the latest 4-23-2014 Debian Image from Beagleboard.org. (Audio levels are still low so need to add instructions for fixing that. TBD)

Instructions are from this thread: https://groups.google.com/forum/#!topic/beagleboard/81TsiNp4Bok

Step 1 copy the audio device tree overlay (source) to /lib/firmware

Step 2 compile the device tree overlay - good instructions here https://learn.adafruit.com/introduction-to-the-beaglebone-black-device-tree?view=all#compiling-an-overlay dtc -O dtb -o BB-BONE-AUDI-02-00A0.dtbo  -b 0 -@ BB-BONE-AUDI-02-00A0.dts

Step 3 nano /boot/uboot/uEnv.txt

Remove the # from in front of this line Note: you only need to disable BB-BONELT-HDMI. BB-BONELT-HDMIN will not conflict with your audio cape.

optargs=capemgr.disable_partno=BB-BONELT-HDMI

Step 4 export SLOTS=/sys/devices/bone_capemgr.*/slots echo BB-BONE-AUDI-02 > $SLOTS

Audio now works

Tests for audio (need to add mixer volume changes, levels are defaulted LOW): speaker-test arecord -r 44100 -c 1 -f S16_LE -t wav -vv -d 25 example.wav aplay example.wav