How low did the STM go?

So i set out on my STM low power Alice in Wonderland crusade and slipped quietly into the rabbit hole…

Hang about! Seems Oberon have already been here!!!


Quick and dirty VS project and here are the results with a STM32F401 being powered by a single cell lipo (mA’s measured at the battery)

So thanks to the magic from Oberon i made it out of the rabbit hole with my sanity intact :smiley:

Ok…maybe the end of the video suggests otherwise :whistle:


Yeah!!! Baby! :clap:

“Unfortunately this video is not available in your Country (Germany) because it might contain Music form SME, which bla bla GEMA” :frowning:

Nice work. I assume going “full fit” [sic] is doing some work and snooze is just sitting idle a th a thread.sleep().

The starting power draw is pretty low already.

@ Justin -

BTW, get a better camera, I can barely see the board :wink:

@ Reinhard Ostermeier - what about now?

@ hagster - Full tit id a tight loop - Snooze is Thread.Sleep and Sleep is you guessed it…

And yes the 401’s are pretty good on the Go Juice :slight_smile:

@ Architect - :smiley:

using System;
using System.Threading;
using Microsoft.SPOT.Hardware;
using SmartSensor;

namespace SmartSensorTest
    public class Program
        private static SmartSensor.Hardware.UserLed _led;
        private static InterruptPort _key; 
        public static void Main()
            _key = new InterruptPort(STM32.Pin.PA4, false, Port.ResistorMode.PullDown, Port.InterruptMode.InterruptEdgeHigh);
            _key.OnInterrupt += key_OnInterrupt;
            _led = new Hardware.UserLed();

        static void key_OnInterrupt(uint data1, uint data2, DateTime time)
            int n = 500000;

            while (n > 0) n--;

            PowerState.Sleep(SleepLevel.DeepSleep, HardwareEvent.GeneralPurpose);

No, still the same.

@ Reinhard Ostermeier - i ticked the box…

Your video may include music that is owned by a third party.
Your video is available and playable.
Copyright details:

“Faithless-Insomnia”, sound recording administered by:

Anywho the answer to the question is


@ Reinhard Ostermeier - not a lot to see apart from a multimeter and a pixelated board.

Current goes from about 27mA active to 11mA idle and 1mA sleep.

@ hagster - you can have a pixelated board if you drive down the A1 :wink:

@ Justin - I think we had a race condition there. Forgot to set the Sync Lock.

@ hagster - i have that problem alot :smiley:

I’d love to, but I’m on daddy duty.

In Germany, most of the Videos with Music are not playable, because the GEMA (organization to collect Money for others Music) can not agree with YouTube how much they have to pay per view ::slight_smile: