Description

MPD is a lean, powerful headless music player. There are numerous clients in many different form factors ref: link.

The aim of the mpd-avr-client project is to explore the practicality of using an AV Receiver as a client for MPD. This project is built using

• a Raspberry Pi 3 for development
• a Yamaha RX-V385 for testing
  • a Raspberry Pi Zero is used for testing
  • the Raspberry Pi is the only device connected to the AVR via HDMI
• a VMA317 Infrared Receiver breakout board

The objectives of the project are to use

• the AVR infrared remote control as input
• the AVR built-in display to feature MPD status and playlist selection
• the AVR connected speakers to output sound

Prerequisites

mpd - a headless music player

mpc - a terminal client for mpd, it is used for subscribing to mpd events

cec-client - a TTY application used for subscribing to CEC events and sending commands to the AVR

gatttool - an application used for Bluetooth communication with smart LED strips

ir-keytable - an application used for configuring IR protocol support

evtest - a TTY application used for grabbing input events

Follow this link to see a setup guide on Trixie

Usage

Installation

$ npm i -g mpd-avr-client

Figure out where to put music

$ cat /etc/mpd.conf | grep music_directory

[!TIP]

The configuration looks like this:

music_directory                 "/var/lib/mpd/music"

Add a playlist to the music directory

$ sudo mkdir "/var/lib/mpd/music/playlist 1"
$ cd "/var/lib/mpd/music/playlist 1"
$ sudo ln -s "/path/to/song/file" ./

Launch

$ mpd-avr-client

[!WARNING]

mpd-avr-client manages the playlist_directory, please backup the directory

Launch on startup

$ sudo touch /etc/systemd/system/mpd-avr-client.service
$ sudo vim /etc/systemd/system/mpd-avr-client.service

Copy and paste:

[Unit]
Description=MPD AVR Client Service
After=network.target

[Service]
Type=simple

# Enable all IR protocols
ExecStartPre=/usr/bin/ir-keytable -p all

# We source nvm.sh to ensure the environment is ready, then launch the app with its flags
ExecStart=/bin/bash -c 'export NVM_DIR="/home/pi/.nvm" && . $NVM_DIR/nvm.sh && mpd-avr-client -v 35 -t "tx 15:44:69:09" -T 48 -b /home/pi/.mpd-avr-client/bravia-launch-profile.json -r /dev/input/event0 -R /home/pi/.mpd-avr-client/yamaha-bravia-mapping.json -g /home/pi/.mpd-avr-client/govee-launch-profile.json'

Restart=always
RestartSec=5

# Logs go to journalctl -u mpd-avr-client
StandardOutput=inherit
StandardError=inherit

[Install]
WantedBy=multi-user.target

[!NOTE]

See commands/main.md for option detail

install service

$ sudo systemctl daemon-reload

$ sudo systemctl enable mpd-avr-client
$ sudo systemctl start mpd-avr-client
$ sudo systemctl status mpd-avr-client

Smart TV integration

The mpd-avr-client project is setup to avoid connecting TV to the AVR via its HDMI ports i.e. use optical or RCA for TV audio. This setup cuts off CEC communication between the AVR and the TV to avoid unwanted propitiatory behaviours that are baked into these devices and give rise to unpleasant surprises at runtime. However, some traits bring convenience and those shall be re-implemented.

As an experiment, the mpd-avr-client project integrates with the Bravia API to

• bring back the automation of powering on TV (and putting TV in standby), and
• provide the convenience of launching an Application on the TV (as an option)
• relay remote control keypress events to the TV

This experimental integration can be enabled by creating a TV launch profile and referencing the profile through the -b option e.g.

$ touch ~/.mpd-avr-client/bravia-launch-profile.json
$ vim ~/.mpd-avr-client/bravia-launch-profile.json

copy + paste:

{
  "hostname": "<bravia__ip-address>",
  "preSharedKey": "<bravia__pre-shared-key--if-configured>",
  "appTitle": "e.g. Kodi"
}

Infrared signal is captured by the infrared receiver breakout board and decoded by the Linux kernel (lirc). The mpd-avr-client project provides a solution to relay AVR remove control keypress to the TV by mapping the decoded infrared signal to ircc code and send the code to the TV. This mapping is created using the map-keys sub command:

$ mpd-avr-client map-keys -r <ir-receiver-path> -b <bravia-launch-profile.json> -C <output-file-directory>

[!TIP]

run evtest to figure out the path to the infrared receiver

see commands/map-keys.md for details

The Bravia TV launch profile is supplied under the -b option and the remote control mapping is supplied under the -R option. See commands/main.md for examples.

[!TIP]

the -t option is required when using the -b option and the -R option

Smart LED strip for TV integration

As an experiment, the mpd-avr-client project integrates with Govee through Bluetooth to automate the power cycle of LED light strip

This experimental integration can be enabled by creating an LED launch profile and referencing the profile through the -g option e.g.

$ touch ~/.mpd-avr-client/govee-launch-profile.json
$ vim ~/.mpd-avr-client/govee-launch-profile.json

copy + paste:

{
  "macAddress": "<govee__mac-address>",
  "rowNumberHex": "<power__row-number>"
}

[!NOTE]

The Bluetooth MAC address can be found by listing Bluetooth devices with this command:

$ sudo hcitool lescan

The row number is the memory location for sending power management commands and it's typically 0x0014 for Govee. Use this command to list all row numbers:

$ sudo gatttool -t random -b <govee-bluetooth-mac-address> --characteristics

The Govee LED launch profile is supplied under the -g option. See commands/main.md for examples.

[!TIP]

the -t option is required when using the -g option