This is a simple radio application using the DAB+-receiver board from uGreen.

You need the following components:

• a Raspberry Pi with 2x20 pins (a Pi-Zero will be fine)
• the DAB-Board from uGreen either with long pins or
• a pin-multiplexer board
• a rotary-encoder
• jumper-wires

Attach the DAB-Board to the Pi. Connect the rotary-encoder as follows

• CLK: GPIO17
• DATA: GPIO27
• SW: GPIO22
• Vcc: 3V3
• GND: GND

Install (copy) the program radio_cli from the uGreen-site to /usr/local/sbin/radio_cli. Follow the user's guide from uGreen to configure your system for use with the DAB-Board. Test the board and verify that it works.

Run

radio_cli -b D -u -k

This will do a full scan of all radio-frequencies and create a file ensemblescan_xxx.json. Copy this file to /root/stations.json.

Download and install the software of this project:

git clone https://github.com/bablokb/simple-dab-radio.git
cd simple-dab-radio
sudo tools/install

This will

• copy the application program /usr/local/sbin/simple-dab-radio.py
• install a systemd-service for the program
• activate the rotary-encoder in the file /boot/config.txt

You need a reboot after installation. The systemd-service will automatically start simple-dab-radio.py during boot and stop the board cleanly during shutdown.

Pushing the rotary-encoder will switch between tuning and volume-control. Note that the DAB-Board needs some time to tune to the selected radio-station, so don't turn the knob too fast. Changing the volume is faster.

The application also supports I2S-setups. If you wan't to use I2S, then follow uGreen's user's guide first to setup I2S for the board.

To activate I2S for this application, you have to edit the configuration file /root/.simple-dab-radio.json and set active: 1:

{
  "volume":  62,
  "station": 12,
  "name": "BR Klassik    ",
  "i2s": {
    "active": 1,
    "vol_cmd": "amixer -q set PCM {0}%",
    "vol_max": 100, 
    "play_cmd": "arecord -D sysdefault:CARD=audiosensepi -c 2 -r 48000 -f S16_LE -q | aplay -q"
    }
  }

Depending on your hardware, you might also have to change the mixer command (vol_cmd) and the aplay options within the play_cmd.

Some ideas for improvements:

• use TTS to announce the selected station (works only with I2S)
• use a small I2C-OLED-display (e.g. for station-logo)
• only tune if the knob is at rest