Tildagon Internet Radio

An MP3 internet-radio app for the EMF 2024 Tildagon badge. iPod-Classic inspired UI with themes, live volume control, swappable station list.

![controls: ▲▼ stations · ◀▶ volume · A play/stop · B exit · ▲▼ hold 2s themes]

What it does

• Streams plain HTTP MP3 (Icecast / Shoutcast) over WiFi.
• Decodes with minimp3 (public domain), compiled into the firmware as a user C module — see drivers/mp3/.
• Plays via I²S to an external DAC (PCM5102A in this build) on a hexpansion port. See hardware wiring details for more.
• Stations are user-editable via a JSON file.
• Themes, volume, last-played station persist across reboots.

Installing the app

mpremote mkdir :/apps/radio || true
mpremote cp app.py        :/apps/radio/app.py
mpremote cp __init__.py   :/apps/radio/__init__.py
mpremote cp metadata.json :/apps/radio/metadata.json
mpremote cp stations.json :/apps/radio/stations.json
mpremote reset

or just install from the badge App store.

Controls

Button	Action
▲ / ▼	Previous / next station
◀ / ▶	Volume −5 % / +5 %
A (CONFIRM)	Play / stop
B (CANCEL)	Exit to launcher
▲ + ▼ hold 2 s	Cycle visual theme

Holding ▲ and ▼ together shows a progress bar at the bottom of the screen; release before it fills to abort.

Stations

Stations are read from /apps/radio/stations.json. Default ships with Rainwave's five mounts, Classic FM, and a few SomaFM channels. Edit the file and reset the badge to apply.

[
  {"name": "Rainwave All",  "url": "http://allstream.rainwave.cc:8000/all.mp3"},
  {"name": "Classic FM",    "url": "http://media-ice.musicradio.com/ClassicFMMP3"},
  {"name": "SomaFM Groove", "url": "http://ice1.somafm.com/groovesalad-128-mp3"}
]

Limits:

• HTTP only — no HTTPS / TLS.
• Direct stream URLs only — .m3u / .pls playlist files won't auto-resolve. If a station gives you a playlist link, open it in a browser/text editor and grab the actual stream URL inside.
• MP3 codec only. AAC, FLAC and Opus streams won't decode (libhelix's AAC decoder could be added as a separate user C module if needed).

If stations.json is missing or malformed, the app falls back to a built-in default list so it still works out of the box.

Themes

Hold ▲ + ▼ for 2 s to cycle. Themes:

Theme	Vibe
iPod LCD	Cream-grey background, black text (default)
Solarized	base03/base02 dark with yellow accent
Tildagon	Pale-/mid-/dark-green from the badge palette
B&W Inverted	Pure black / white terminal style

The chosen theme persists in /apps/radio/settings.json.

Settings

/apps/radio/settings.json is auto-written when you change station, volume, or theme. It looks like:

{"station_idx": 4, "volume": 70, "theme_idx": 1}

Delete the file to reset to defaults.