Departures

A self-playing ambient ensemble for the Workshop Computer. Choose the original Bells ensemble or warmer Wood Chimes at startup. Stable 0.5.1 lowers the pads by approximately 2.18 dB compared with 0.5.0, giving the melody more room during overlapping pad swells. Melody and bass levels retain their established balance. See the archive for earlier releases and original experiments.

Install and choose a sound

Flash Departures_0.5.1.uf2 using BOOTSEL. It fits both 2MB and 16MB program cards.

1. Hold Z Down while powering on or pressing reset, and keep holding it. After the panel settles, the sound-choice LEDs appear. Audio is muted while selecting; incoming musical triggers are ignored.
2. Turn Main clearly left of noon for Bells, or right of noon for Wood Chimes. A small centre deadband prevents jitter once a choice is made.
3. Release Z to confirm and start. The normal fade-in follows. Main returns to Activity, so adjust it to your preferred playing position after release.

Normal boot without holding Down always selects Bells, regardless of Main's position. The choice lasts until reset and is not saved to flash.

What Wood Chimes changes

• The four phrase voices use a rounded fundamental with a rapidly damped upper resonance. Their body rings for less time, with a more percussive, woody attack.
• Each loop has a slightly different resonance relationship. X controls strike brightness; its strongest effect is heard on new strikes.
• The pad has less upper-harmonic emphasis for a warmer accompaniment. X still changes its colour. The bass voice and its level are unchanged.
• The quieter one-quarter melody mix, stored accents, octave answers, note mutations, rests, harmony, tide and external-input send are retained.

Playing controls and jacks

Output tuning remains 1V/oct, 0V = C2 (MIDI36), calibrated where available. Triggers last 10ms after approximately 1ms of pitch settling. The selected palette changes internal audio only, not the pitch/gate amplitudes or the CV roles.

Selecting a scale and reading the LEDs

CV In 1 selects the scale directly; no trigger is needed. All seven scales share a D tonic. Changing CV1 changes the scale even while Z is in Hold.

The six physical LEDs are numbered as follows, viewed from the front:

1 2
3 4
5 6

With a cable plugged into CV In 1, the top two LEDs and the middle-left LED (1, 2 and 3) show the selected scale. Read the combination of lights using the table below. “LEDs lit” lists physical LED numbers: “1 and 3” means the top-left and middle-left LEDs are on, with the top-right LED off.

For example, apply about 1.79V to CV1: LEDs 1 and 2 light to show D major. Raise it to about 2.50V: only LED 3 lights for D Mixolydian.

Unplug CV1 to return to D Dorian. LEDs 1–3 then gently brighten and dim with the pad voices; they show the scale only while CV1 is patched. Voltage boundaries have a small deadband to prevent flickering between scales, so use the centre voltages above when testing. Negative voltages select Dorian; above 5V selects Locrian.

CV2 chooses a chord, independently

CV In 2 uses the same voltage ranges to prepare chord degrees I, II, III, IV, V, VI and VII, in order, within the scale chosen by CV1. A rising edge at Pulse In 2 commits the prepared chord. The scale LEDs continue to show CV1's scale throughout; changing CV2 does not change their pattern.

Patching CV2 pauses automatic chord progression; unplugging restores it.

Other LED roles

• LED4 (middle right): melody activity.
• LED5 (bottom left): bright in Hold, otherwise dim when an external clock is patched.
• LED6 (bottom right): latched timing warning; reset clears it.

While holding Z Down at startup, LEDs 1–4 temporarily show the sound choice instead: 1 and 3 for Bells, 2 and 4 for Wood Chimes. Normal playback LED roles return when Z is released.

Build and checks

This release includes source, licenses, tests and firmware:

export PICO_SDK_PATH=/path/to/pico-sdk
cmake -S . -B build -DCMAKE_BUILD_TYPE=Release -DPICO_BOARD=pico
cmake --build build -j2
make -C test check preview
python3 tools/package_release.py

Host checks use ASan/UBSan. They retain the 0.4.1 checks and add startup default, selector mute/debounce, choice hysteresis, boot-gesture isolation, two-palette score/CV matching, damped wood-voice behaviour and a Wood Chimes stress run. The preview target generates both three-minute WAVs under test/out/ (not tracked). The Wood preview includes a half-second boot-selection hold before playback.

Optional compiled ARM timing estimates require separate Unicorn/Capstone packages:

cmake -S . -B build-bench -DCMAKE_BUILD_TYPE=Release -DDEPARTURES_BENCH=ON
cmake --build build-bench -j2
python3 test/bench.py build-bench/Departures.elf
python3 test/bench.py build-bench/Departures.elf --wood

See BUILD_REPORT.md, TEST_PROTOCOL.md, CHANGELOG.md and NOTICE.txt. The catalogue download is the stable image linked above. See experimental/README.md for experiment status and FUTURE_PLANS.md for the completed palette plan. It uses no samples or external sound banks.

Credits and licensing

Departures was developed by Adrian Vos (soveda) with AI assistance from Codex. The original card application is MIT licensed; see LICENSE.

• Charles Vestal — AMB-1: musical inspiration for an ensemble of breathing voices, unequal phrase loops and evolving harmony in an ambient space. AMB-1 is credited as inspiration; its source code, presets, sounds, interface and firmware are not included.
• Chris Johnson — ComputerCard 0.4.0: the unchanged hardware framework, copyright 2024–2026, MIT. The header and license are in vendor/ComputerCard. Upstream ComputerCard.
• Matt Allison — Equanimity: the ARM timing test adapts its cycle model and ComputerCard field-offset helper, copyright 2026, MIT. That testing code is excluded from the normal firmware. Its full license is preserved in licenses/EQUANIMITY_LICENSE.txt. Equanimity also provided a local reference for ambient-card build and hardware setup.
• Raspberry Pi and contributors — Pico SDK: external build dependency and source of pico_sdk_import.cmake; SDK license preserved in licenses/PICO_SDK_LICENSE.txt.
• ARM GNU Toolchain, GCC runtime and Newlib contributors: firmware build and runtime support; notices in licenses/TOOLCHAIN_NOTICES.txt.
• Tom Whitwell, Music Thing Modular and repository contributors: the Workshop Computer platform, examples, contribution conventions and metadata tooling.

See THIRD_PARTY_NOTICES.md for the dependency inventory and NOTICE.txt for consolidated redistribution notices. Keep uf2/NOTICE.txt with the firmware when sharing it.