These instructions are for installing mpd_oled with a binary package on Volumio 3.
The binary package should be the best option for most people, but if you would like to build and install the current mpd_oled repository code then see Install instructions for Volumio 3 using source.
Volumio should be installed. Ensure a command line prompt is available for entering the commands below (e.g. use SSH.)
Configure your system to enable I2C or SPI, depending on how your OLED is connected.
I use a cheap 4 pin I2C SSH1106 display with a Raspberry Pi Zero. It is
wired like this.
In /etc/modules I have the line i2c-dev (included by default).
In /boot/config.txt I have the line dtparam=i2c_arm=on (included by default).
The I2C bus speed on your system may be too slow for a reasonable screen
refresh. Set a higher bus speed by adding the line
dtparam=i2c_arm_baudrate=400000 to
/boot/userconfig.txt (or use /boot/config.txt for Volumio versions before
2.673), or try a higher value for a higher screen refresh (I use
dtparam=i2c_arm_baudrate=800000 with a 25 FPS screen refresh)
sudo nano /boot/userconfig.txt
Restart the Pi after making any system configuration changes.
I use a cheap 7 pin SPI SSH1106 display with a Raspberry Pi Zero. It is
wired like this.
In /boot/userconfig.txt (or use /boot/config.txt for Volumio versions before
2.673) I have the line dtparam=spi=on.
sudo nano /boot/userconfig.txt
Restart the Pi after making any system configuration changes.
If the mpd_oled clock does not display the local time then you may need to set the system time zone. Set this in the UI, or run the following command for a console based application where you can specify your location
sudo dpkg-reconfigure tzdata
This will download and install the most recent mpd_oled binary package (the second command might take a couple of minutes to run)
wget -N http://pitastic.com/mpd_oled/packages/mpd_oled_volumio_install_latest.sh
sudo bash mpd_oled_volumio_install_latest.sh
The next instruction configure MPD to make a copy of its output to a named pipe, where Cava can read it and calculate the spectrum. This works reliably, but has two disadvantages: the configuration involves changing a Volumio system file, which must be undone if Volumio is to be updated (see below); the spectrum only works when the audio is played through MPD, like music files, web radio and DLNA streaming. Creating a copy of the audio for all audio sources is harder, and may be unreliable -- see the thread on using mpd_oled with Spotify and Airplay
Configure MPD to copy its audio output to a named pipe
sudo mpd_oled_volumio_mpd_conf_install
Note: after running this command, the next time you try to update Volumio
the update will fail
with a system integrity check error. The change can be undone by running
sudo mpd_oled_volumio_mpd_conf_uninstall, then after the Volumio update
run sudo mpd_oled_volumio_mpd_conf_install to re-enable the audio copy.
Note: The program can be run without the audio copy enabled, in which case the spectrum analyser area will be blank
The OLED type MUST be specified with -o from the following list: 1 - Adafruit (SSD1306, SSD1309) SPI 128x64, 3 - Adafruit (SSD1306, SSD1309) I2C 128x64, 4 - Seeed I2C 128x64, 6 - SH1106 (SSH1106) I2C 128x64. 7 - SH1106 (SSH1106) SPI 128x64.
An example command, for a generic I2C SH1106 display (OLED type 6) with a display of 10 bars and a gap of 1 pixel between bars and a framerate of 20Hz is
sudo mpd_oled_service_edit -o 6 -b 10 -g 1 -f 20
For I2C OLEDs (mpd_oled -o 3, 4 or 6) you may need to specify the I2C
address, find this by running, e.g. sudo i2cdetect -y 1 and then specify
the address with option -a, e.g. sudo mpd_oled_service_edit -o6 -a 3d ....
If you have a reset pin connected, specify the GPIO number with option -r,
e.g. sudo mpd_oled_service_edit -o6 -r 24 .... Specify the I2C bus number,
if not 1, with option -B, e.g. sudo mpd_oled_service_edit -o6 -B 0 ...
For, SPI OLEDs (option -o 1 or 7), you may need to specify your reset pin GPIO number (option -r, default 25), DC pin GPIO number (option -D, default 24) or CS value (option -S, default 0).
If your display is upside down, you can rotate it 180 degrees with option '-R'.
Once the display is working, play some music and check the spectrum display is working and is synchronised with the music. If there are no bars then the audio copy may not have been configured correctly. If the bars seem jerky or not synchronized with the music then reduce the values of -b and/or -f.
If you run sudo mpd_oled_service_edit without options the service
file will open in an editor, allowing the full service file to be
changed, and not just the mpd_oled options.
If the mpd_oled options are valid the display will be started after the editor is closed, and will also be configured to start a boot
A few selected commands that can be used to control the service
sudo systemctl enable mpd_oled # start mpd_oled at boot
sudo systemctl disable mpd_oled # don't start mpd_oled at boot
sudo systemctl start mpd_oled # start mpd_oled now
sudo systemctl stop mpd_oled # stop mpd_oled now
sudo systemctl status mpd_oled # report the status of the service
Uninstall with
sudo apt remove mpd-oled