CircuitCo:Audio Cape RevB

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Descriptions

Audio Cape

The Rev B Audio Cape provides an line level stereo audio input and output on the BeagleBone and BeagleBone Black.









Revision Changes

Revision A1

DISCONTINUED: Audio Cape Rev A Wiki Page

Revision B1

Redesign of the Audio cape to lower cost, for compatibility with the BeagleBone Black, and to switch to the TLV320AIC3104 codec.

Software Support & Compatibility

The device tree overlay is available at the bottom of this page. Please note, the current Angstrom build lacks kernel patches for the audio codec used on this cape, if you attempt to use it on the Angstrom image you will hear audio at double speed or static. The current Debian images have the required patches and will play audio normally.

Specifications

Followings are some specifications of the Audio Cape:

Mechanical Specifications

Size 2.15" x 2.825"
Layers 2
PCB Thickness .062"
RoHS Compliant Yes



Signal Usage

Audio Cape
Power VDD_3V3EXP
Audio I2C2_SCL
I2C2_SDA
GPIO3_21
SPI1_CS0
SPI1_DO
SPI1_DI
SPI1_SCLK

Distributors

Product Images



Documentations

Audio Cape Revision B1

Setup Notes

These instructions got the audio cape working for me (User:JesseForgues).

Audio levels low so need to add instructions for fixing that.

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