Internet radio for Raspberry Pi with eInk dispay

Setup

Note that this code will only run on a Raspberry Pi (tested on a Pi Zero 2 and a Pi 4), needs Python 3.9+

1. Enable SPI in sudo raspi-config (under Interface options)

2. Install dependencies: sudo apt install mpv bluez-alsa-utils python3-dev

3. create and activate venv: python -m venv ./venv and source ./venv/bin/activate

4. Install Python dependencies: pip install -r requirements.txt

5. Added dtoverlay=spi0-0cs to the bottom of /boot/firmware/config.txt (see raspberrypi/bookworm-feedback#179 )

6. The lookup tables for Pervasive displays are not open source. You need to contact them and then add to src/display/pervasive_luts.py. It needs to have 2 arrays with hex code ints like: fastLUT=[0x00,0x23] globalLUT=[0x12,0x34]

7. (optional) raise BT codec quality: Run sudo systemctl edit bluealsa follow instructions and add --sbc-quality=xq to bluealsa's startup parameter.

8. (optional) The radio has a small built-in webserver to control it, you can access it on port 80. This port is only accessible for root users, to circumvent this:

   • run which python
   • run realpath [which result]
   • run sudo setcap 'cap_net_bind_service=+ep' [realpath result]

Run the project

python3 main.py

You can set it to auto-run on startup e.g. cron:

1. Log in as the user you want to run it.
2. run crontab -e and enter here: @reboot cd /home/[PATH_TO_REPO]/pi-radio/ && start_radio.sh (set it to executable with chmod +x, debug with journalctl -u cron.service)

Hardware components

audio output: https://www.adafruit.com/product/3678

eink display: https://www.pervasivedisplays.com/product/5-81-e-ink-displays/

Errors

No sound

• Check alsamixer, it should display the Adafruit card. If not you can change it with sudo and run the program as root.

• Try connecting your BT speaker manually with bluetoothctl and check for errors.

• bluealsa-aplay --list-devices -- should list your BT device

• /bin/echo -e "show\ninfo 12:23:34:45:56" | bluetoothctl -- should list your BT device

• dbus-monitor --system -- Lists dbus messages. You should see here when BT connects

• sudo btmon -- shows low level BT messages. You should see button presses here

• Uninstall pulseaudio, it conflicts with bluealsa

BT play/pause button does not work

• Check with evtest where your BT device is connected to, now its looking for a device whose name contains 'AVRCP'

gpio busy

check whats using it with cat /sys/kernel/debug/gpio

TODO/bugs

• use libmpv instead of mpv, so it doesnt depends on distro updates
• show errors/exceptions on the web control interface Add New features:
• Add "Audio Jack" to menu, when selected play via Jack.

Current BT/Jack logic: On startup try to connect to a saved BT device. When connected/disconnected to a BT device OR pressing play on a device OR changing channel play on BT if its connected, on Jack if its not.