Wolfson DAC for the Raspberry Pi 1

Necroed my old Raspberry Pi 1 with the Wolfson DAC that was collecting dust.

Card specs^[1]:

• Multiple analogue I/O
• Digital IO (SPDIF)
• Class-D amp for direct connection to speakers (some headers need to be soldered)
• Stereo MEMS microphones
• 24-bit, 192kHz output

Much better than on-board audio^[2]:

• Analoge sound generated using PLL
• 11-bit, 48kHz analogue out
• no input

Used to require some image from element14/farnell. Now supported in official images. (For quite a while now^[3]...)

Files to edit

/boot/config

...
# Wolfson audio
dtoverlay=rpi-cirrus-wm5102

/etc/modprobe.d/cirrus.conf

softdep arizona-spi pre: arizona-ldo1
#Fix card numbering, wolfson(cirrus) 0, onboard 1
options snd slots=snd-soc-rpi-cirrus,snd-bcm2835

Configuring the card's inputs and outputs

Download helper scripts here. Extract these and put them somewhere in your PATH

These are basically amixer scripts to help you configure for various tasks:

• Record_from_*.sh to choose recording input
• Playback_to_*.sh to choose output
• Reset_paths.sh to set inputs and outputs to defaults.
• Cirrus_listen.sh to configure IO mixing. (eg. SPDIF to lineout)

Appendixes

Original docs here

Finally, some high-res audio to play with here.