Battery

This watch face is very simple and has no controls to speak of. It displays the battery voltage as measured by the SAM L22’s ADC.

You can expect your battery to hover at or near 3 volts for the first few months of use. After a while it will start to decline. This is normal, and you can continue using your watch as it declines. As it declines to, say, 2.6 volts, you may also note that the voltage sags when the buzzer beeps or when you light the LED, but then recovers. This too is normal.

Once the battery voltage is at a steady reading of ~2.4 volts, it’s likely your battery’s demise is days away.