MoteinoMEGA based Data Logger

Ed Mallon runs the Cave Pearl Project which is all about “developing a data logging platform from inexpensive pre-made breakout boards, and are using this at the heart of new environmental sensors that anyone can build.” Ed is also a contributor in the forum, and has posted a great in-depth tutorial that steps through making a submersible data logger. From the blog’s own summary:

In this tutorial, a logger is built using a 3.3v Moteino MEGA with a 1284p CPU @ 16Mhz, w 4K eeprom,16K SRAM for variables & 128K program space. Considerably more than the 328’s 1K eeprom, 2K ram & 32K progmem. Also has a spare serial port for GPS/NEMA sensors.

MoteinoMEGA based Cave Pearl in ‘Prototyping Trim’ with I2C OLED screen & ADS1115 ADC. INT1 & Aref jumpered. The built also includes an RTC backed up by a coin cell.


It’s great to see Moteinos being put to serious work in such interesting and niche projects. While a custom PCB could be built to reduce the amount of wiring and make for a more compact logger/breakout solution, this tutorial is targeted and perfect for those who want to learn the skill of building data loggers or similar projects using off the shelf components. Thanks Ed and the Cave Pearl Project!

MoteinoMEGA with trace antenna

Over the past few months a friend has helped me create a MoteinoMEGA variant with a trace antenna tuned for between 768Mhz to 1.16GHz. So this should be great for 868-915mhz. I’ve tested this variant myself (915mhz) and I was surprised how well it performs compared to a wire monopole (which will still be better given the type of antenna). I did not do extensive testing but I am pretty confident this turned out as a great antenna and I am offering the remainder of this batch for those eager to have one and perhaps do more testing on their own. Depending on the response I may or may not ever make more of these, we shall see. The same antenna could be used with any other Moteino but I want to see the response of the users before I invest too much capital in new batches of Moteinos. The ANT pad and u.FL footprint are still there if for some reason the user wants to cut off the trace antenna and use one of those instead with a monopole or different antenna. Otherwise everything else is the same, well, except the yellow soldermask which has a nice orange hue from my new PCB supplier. I will offer these with RFM69W/HW in 868/915mhz or without a transceiver, your choice. Enjoy.

New product: MoteinoMEGA-USB with LoRa footprint

There is a new variant of Moteino available: MoteinoMEGA with LoRa footprint and onboard FTDI USB-serial converter. This is the first MEGA USB variant. It will also work with RFM69HCW radios if you want a MEGA-USB with RFM69, but for now you will need to source your RFM69HCW from somewhere else. Otherwise all sketches and examples should work as before. I have yet to create a pinout diagram for this variant but it’s pretty much the same as the MoteinoMEGA. Here is a shot of both sides, shown with a RFM95 LoRa transceiver soldered on the bottom:

MoteinoMEGA available now!

UPDATE: Library/Eagle files/MEGA Arduino Core/Example update notes are here.

It’s alive and it’s BLUE!

After long PCB manufacturing delays and a lot of headaches, the PCBs finally arrived, and I assembled the first batch of MoteinoMEGAs today and they are available in the shop.

Other news:

  • MoteinoUSB is also back in stock now.
  • Worth noting that all Moteinos have started to ship with MCP1703 regulator which allows up to 16V input.
  • MightyBoost is being worked on and should become available in a few days if all is well.
  • There is a major release of patches coming to the RFM69 library, wireless programming library, SPIFlash library, along with the new MoteinoMEGA arduino core that will be released soon.
  • DualOptiboot is will also be upgraded to V5 and is compatible with Moteino, MoteinoUSB and MoteinoMEGA. All these boards are wirelessly programmable via DualOptiboot and the FLASH chip. The MEGA board will have a limit of 64kb wireless image upload even though the total flash available is 127/128KB (DualOptiboot takes 1K).

Documentation and product pages are being worked on, so stay tuned for all these releases. Here is the pinout diagram for MoteinoMEGA: