A battery powered Mysensors node from an Arduino Pro Mini clone

10 Sep 2018

It is not very difficult to build a reasonably nice MySensors node based on very affordable hardware. This is a reminder for myself in order to be able to reproduce one.

A basic battery powered Mysensors node

Based on: the documentation by MySensors and a 3.3V 8MHz Arduino (clone) Pro Mini from the usual sources (Banggood, AliExpress).

Handy pinout guide

Perform the hardware mods from above link:

Make an Arduino ISP programmer

In order to reflash the bootloader, we need an In-System Programmer (ISP). It is possible to use another Arduino as the ISP, and I like to use another Pro Mini.

Hardware

I follow the following schematic: Fritzing schematic of Pro Mini ISP

And in reality on a breadboard, it looks like this (with a LED added to pin 9):

Breadboard Pro Mini ISP

Flash the ISP firmware

Install boot loader:

In order to get a lower Brown Out voltage, we need to flash a new bootloader. Actually that's not strictly required, but it's the easiest way. I am using Optiboot bootloaders compiled by Gert Sanders, so many thanks to him.

Test

Upload the real script

I use platformio to run my projects, so uploading is pretty easy: