Gestures

A Puck has one button and three LEDs, so the button’s gestures are its whole interface. They are told apart in packages/sensors/firmware/button.ts; what each does is a setting (packages/sensors/firmware/gestures.ts), acted on in packages/sensors/firmware/main.ts.

The gestures

Gesture	Told apart by
Press	One short press, no second within 350 ms
Double press	Two short presses, each within 350 ms of the last
Triple press	Three; reported at once on the third
Long press	Held 0.6 to 10 seconds
Hold	Held 10 seconds or more: opens pairing for 60 seconds, always, so it is never an accident and the way back in cannot be set away

Each of press, double, triple and long press does one of three things, with an LED colour of its own (red, green, blue, or two or three of them together: yellow, cyan, magenta, white):

• Start or stop an activity of a kind (walk, run, hike, cycle, other). While an activity runs, any activity gesture stops it and never starts another, so a bumped gesture can end a session but not replace it (activityAfter in packages/sensors/firmware/gestures.ts). Starting blinks its colour twice, stopping once for 400 ms, and while it runs the colour blinks for 10 ms every 20 seconds, so a glance says it is on.
• Drop a marker: a Button record of the gesture, blinked once for 30 ms. What a marker means (a lap, “moved it to my pocket”) is the reader’s to say.
• Nothing.

By default a triple press starts and stops a walk in green, and press (green), double press (blue) and long press (magenta) drop markers. Datler Sensors sets them with DS.gestures({...}) (Sensor Data Format); installed firmware keeps them in ds.config.

LED	Means
A gesture’s colour, twice	Its activity started
A gesture’s colour, 400 ms	The activity stopped
A gesture’s colour, 30 ms	A marker dropped
The running activity’s colour, 10 ms every 20 seconds	An activity runs
Blue every second	Pairing is open
Blue three times, quickly	A hold with no passkey set: nothing to open
Red five times, from the battery going in	Espruino’s own hard reset ()

Activities

An activity is an interval of a kind, as Health Connect’s exercise session and HealthKit’s workout are. Inside one the step detector counts and a steps record is written each minute, 0 included; outside one the detector is off (it draws about 50 uA by Espruino’s figure) and no steps are written, so the steps a reader sees are the activity’s alone. Temperature and light go on hourly either way, and presses, the battery and the adverts carry on. A reader can start and stop one too, with DS.activity(kind). A device starts with none running.

Pairing

A passkey, once set, means only a reader that paired with it can use the console, and pairing is closed except for the minute a hold opens (Reaching a Puck, Pairing). The passkey is set from a reader with DS.passkey("123456") (six digits; "" for none), which installed firmware keeps in Storage. A reader that already paired keeps getting in with pairing closed; a new one pairs during the window, entering the passkey when its system asks.

Recovery

If every pairing is lost or the passkey forgotten, the way back in is Espruino’s hard reset: the button held from the battery going in for about 10 seconds, until the red LED blinks five times. It clears pairings and saved code, so the firmware is installed again afterwards. Let go sooner and the Puck starts its bootloader or skips saved code instead (Puck.js, Firmware).