E.getPowerUsage to estimate power consumption

gfwilliams commented 5 months ago

We don't know exactly how much power is being used by certain things, but on some devices we do have an idea, and we could expose that to the user.

Check the bluetooth connection state / connection / advertising interval and guess on BLE power usage
Compare SYSTICK (system clock ticks) against RTC to figure out how many cycles we executed (on nRF52 it's roughly 4mA if running all the time)
Are LEDs on? 8mA per LED/etc
On Puck.js/Bangle/etc we will know if certain peripherals are powered on and roughly how much they draw

So it could report:

>E.getPowerUsage()
={
 usage : 5.5, // mA
 d : [
  code : 2,
  BLE : 1,
  accel : 0.5,
  LCD : 2,
  // ...
 ]
}

We could implement something using build_jswrapper.py so it's easy to extend for different devices.

Any thoughts? It feels like a good feature as users often don't have a way to easily check power usage.

halemmerich commented 5 months ago

I like this, it would reduce the code of the powermanager widget by a lot. Backlight power use on the bangles depending on current brightness would be nice too as it is a huge draw.

gfwilliams commented 5 months ago

Fixed with fa73e3103165573bf18f75a8e40e46dee6189ccc

espruino / Espruino

E.getPowerUsage to estimate power consumption #2492