PLEASE NOTE: This article is obsolete or related to a discontinued product.
Daisy 16 V2 audio adapter
Audio adapter daisy module for Terra and Aria G25 boards based on Wolfson microelectronics WM8731 Audio CODEC
The audio codec used is the WM8731, is low power stereo codec with an integrated headphone driver, stereo line-out, stereo line-in and mono microphone level audio inputs.
WM8731 Codecs is supported by the Linux kernel and works with alsa drivers.
Main features
- Stereo 24-bit, multi-bit sigma delta ADCs and DACs are used with oversampling digital interpolation and decimation filters.
- Highly Efficient Headphone Driver
- Audio Performance : ADC SNR 90dB at 3.3V , DAC SNR 100dB at 3.3V
- Low Power : Playback only 22mW
- Selectable ADC High Pass Filter
- Microphone Input and Electret Bias with Side Tone Mixer
- Dimension: 40x40mm
Pinout
| PIN | Aria G25 |
|---|---|
| 1 3V3 | W24 |
| 2 RF | W16 (PA29) |
| 3 RD | W14 (PA27) |
| 4 TK | W11 (PA24) |
| 5 TF | W12 (PA25) |
| 6 TD | W13 (PA26) |
| 7 SDA | W17 (PA30-SDA0) |
| 8 SCL | W18 (PA31-SCL0) |
| 9 RK | W15 (PA28) |
| 10 GND | W1 |
Wirings
The daisy connectors where to plug this board are:
| Board | Daisy Connector |
|---|---|
| TERRA | D16 |
Kernel configuration and device tree binding
The Kernel configuration, device tree bindings and source patches are available on this article:
Schematics, datasheets and related links
Install alsa-utils
~# apt-get install alsa-utils
Run alsamixer:
~# alsamixer -V all
Configure alsa in this way:
Record and play
Save 5 second of stereo audio in a .wav file:
~# arecord -d 5 -v -v -Dhw:0,0 -f cd record_line_in.wav
Play the .wav file:
~# aplay record_line_in.wav
Change volume:
~# amixer set Master 10%-
