The Things Node - Quick 40uA How-To

End Devices (Nodes)
1

Hi there

I had to spend quite some time getting The Things Node running with 40uA sleep current, so I thought I could give you a quick How-To what you have to do.

There is a forum thread that contains a lot of info on this topic, but it is rather long and not well structured.

The Things Node 40uA HowTo

  1. Open Arduino IDE (v1.8.13) and install TheThingsNetwork (V2.0.6) and TheThingsNode (V2.0.6) via Tools/Manage Libraries

  2. If you have a Node with rather old LoRa module RN2483 firmware version (e.g. V 1.0.1), you need to update this firmware to version 1.0.5 according to this forum post.

  3. Open the File/Examples/TheThingsNode/BatteryMonitorLPP. (Paste in the AppEui and appKey and freqPlan for your gateway/application). When you download the sketch at this point, you would measure approximately 400uA sleep current.

  4. Open the library file /Users/XYZ/Documents/Arduino/libraries/TheThingsNode/src/TheThingsNode.cpp with a text editor and add both lines commented with +++ in the appropriate places.

    void TheThingsNode::deepSleep(void)
    {
    ADCSRA &= ~_BV(ADEN);
    set_sleep_mode(SLEEP_MODE_PWR_DOWN);
    MCUCR |= (1 << JTD);
    USBCON |= (1 << FRZCLK);
    UHWCON &= ~_BV(UVREGE); // +++ disable the USB regulator
    //USBCON &= ~_BV(USBE);
    PLLCSR &= ~_BV(PLLE);
    sleep_enable();
    sleep_mode(); //Sweet dreams!

    //wake up, after ISR we arrive here ->
    sleep_disable();
    PLLCSR |= (1 << PLLE);
    power_all_enable();
    //USBCON |= (1 << USBE);
    UHWCON |= UVREGE; // +++ enable the USB regulator
    USBCON &= ~_BV(FRZCLK);
    ADCSRA |= (1 << ADEN);
    }

Compile, download and enjoy 40uA sleep current. Now if you change the connection interval (which is 5 minutes per default) to e.g. 6 hours, you can run The Things Node from 3x AAA batteries for approximately 2 years now!

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