Loading firmware
Shift+click holds a key; Esc lets go of everything. Knobs: drag any way or wheel to turn, click to push, shift+click to hold down, arrows when focused. The strip under the screen is the touch slider. Map shows the keyboard and MIDI bindings.
Sound starts with the first press

This is the firmware's own UI and audio engine, compiled to WebAssembly. Its demo project has three clips armed, so PLAY starts a groove. The SD card is kept on this device and comes back on reload, without the demo's armed clips; Reset card erases it and starts the demo card again. Web MIDI reaches the firmware as its MIDI port does, except what is mapped to a panel control; USB and the Launchpad have no hardware behind them here, and the capture reaches back 3.4 s because the 5-minute ring file is left out.