If you’ve watched the forum, it’s been suggested to develop a new Moteino board featuring new/more powerful/more flexible or even ARM microcontrollers. Mentioned candidates were the Atmega328PB, STM32, SAMD from Microchip and perhaps others were mentioned over time as well.
Say hello to MoteinoM0 – it features the popular SAMD21G ARM Cortex M0+ 32bit processor (48Mhz, 256kb FLASH, 32kb SRAM). It’s quite an awesome bit of silicon brains and after months of playing with it, tweaking libraries and sketches, testing peripherals and designing add-ons for it, and developing an Arduino package for it that is oriented on LowPowerLab‘s most important points of interest, it is now available to the public.
But SAMD21 has been offered by others for years you say. How is this exciting and why did this take so long? I didn’t want to spam the market with a new clone and claim this is the best thing since Arduino Zero. Here are a few highlights that I think will make MoteinoM0 different and interesting:
- long range wireless programming enabled just like all the other current AVR Moteinos!
- Got low power? You bet! How about 6µA in standby sleep? MoteinoM0 yields the real low power mode achievable by the SAMD21, 7µA in watchdog periodic sleep, +1µA for the external 4MBIT FLASH-MEM chip and radio module
- supports RFM69HCW and LoRa radios, plus secondary radios and add-ons, see below
- a modular design enables compact platform for I2C/SPI/GPIO add-ons, just a few examples to mention:
- break out as many useful and Arduino supported pins as possible in a symmetric and compact board layout
- ease of side castellated mounts allow these add-ons to be mounted directly flat on the PCB without additional headers, here’s a simple weather-node add-on board that only requires one sided soldering and can be easily removed and reused:

- you may also stack above/below using extra headers or solder extension wiring to the side half-holes for quick removal and re-use later:

Here is a quick pin reference and schematic:
A few things about similarity to the standard Arduino Zero:
- this board was designed to be as compatible with Arduino Zero as possible in terms of available MCU functionality
- GPIO and core package is adapted from Arduino Zero, all GPIO is accessible the same way, except PA28 (USB_HOST_EN) which is not connected
- as seen in the reference above, some pins are hardwired to the radio transceiver and SPIFlash (A2/SS for radio, D8 for FLASH-MEM) and used by these modules
- you should be able to use most Arduino examples with MoteinM0 without a lot of hassle. If you’re already familiar with Arduino Zero this board should feel right at home
Read below for why this took “so long”.
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