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Adafruit Feather 32U4 RFM95

Introduction

Section titled “Introduction”

Adafruit Industries was founded in 2005 by MIT engineer Limor “Ladyada” Fried.

Over the years, Adafruit has built tons of Arduino-compatible boards, shields, accessories, books and libraries thus expanding the open source ecosystem created around, but not limited to, Arduino world.

LoRa Communication

Section titled “LoRa Communication”

Feather’s radio module works really fine with AirSpayce’s Radiohead library.

On the second sentence of the Main Page there a link with which you can download the library. As an alternative, you can use the wget command. Open a terminal and follow the steps below to install the Arduino library.

Terminal window
cd ~/Downloads


wget http://www.airspayce.com/mikem/arduino/RadioHead/RadioHead-1.121.zip


# uncompress the archive in a directory called RadioHead
unzip RadioHead-1.121.zip


mv RadioHead ~/Arduino/libraries/

Restart the Arduino IDE.

update from there down

This blog post aims to introduce you to the Adafruit world with a powerful LoRa board.

Technical Details

Section titled “Technical Details”

Here is a detailed list of specifications for Adafruit’s Feather 32u4 RFM95 LoRa board:

  • Processor:
    • ATmega32u4 processor clocked at 8MHz,
  • Memory:
    • 32KB of FLASH memory and 2KB of RAM,
    • 2MB SPI Flash chip,
    • No EEPROM memory
  • Logic/Power:
    • 3.3V logic/power,
    • 3.3V regulator with 500mA peak current output
    • built in 100mA lipoly charger (with LED charging status indicator)
  • 20 GPIO pins:
    • n°7 PWM pins,
    • n°10 analog inputs,
  • Communication:
    • Hardware Serial,
    • Hardware I2C,
    • Hardware SPI support,
    • USB native support
  • Other:
    • 51mm x 23mm x 8mm dimension,
    • Weight: 5.5g

This Feather 32u4 LoRa Radio uses the extra space left over to add an RFM9x LoRa 868/915 MHz radio module. These radios are not good for transmitting audio or video but they provide more range than 2.4 GHz (BT, BLE, WiFi). You should only transmit small data packet.

The radio module provides:

  • SX1276 LoRa® based module with SPI interface,
  • ready-to-go Arduino libraries,
  • use license-free ISM bands
    • ITU “Europe” at 433MHz,
    • ITU “Americas” at 900MHz,
  • +5 to +20 dBm up to 100 mW power output capability (selectable in software),
  • ~300uA during full sleep,
  • ~120mA peak during +20dBm transmit,
  • ~40mA during active radio listening,
  • simple wire antenna or spot for uFL connector

Pinout

Arduino IDE

Section titled “Arduino IDE”

To allow your Feather board to work with Arduino IDE you need to start the IDE and navigate to the Preferences menu.

In the Additional Boards Manager URLs, you need to add the following URL:

Terminal window
https://adafruit.github.io/arduino-board-index/package_adafruit_index.json

To find the most up-to-date list of URLs you can add, please visit the list of third party board URLs on the Arduino IDE wiki.

Here’s a short description of each of the Adafruit supplied packages that will be available in the Board Manager when you add the URL:

  1. Adafruit AVR Boards: support for Flora, Gemma, Feather 32u4, Trinket, & Trinket Pro.
  2. Adafruit SAMD Boards: support for Feather M0, Metro M0, Circuit Playground Express, Gemma M0 and Trinket M0
  3. Arduino Leonardo & Micro MIDI-USB: adds MIDI over USB support for the Flora, Feather 32u4, Micro and Leonardo using the arcore project.

If you have multiple boards you want to support, say ESP8266 and Adafruit, have both URLs in the text box separated by a comma.

Once done click OK to save the new preference settings.

Arduino IDE - Preferences

Now that you have added the appropriate URLs, you can open the Boards Manager by navigating to the Tools > Board menu.

Install Adafruit AVR Borads library. You can optionally also install Arduino SAMD Boards and Adafruit SAMD libraries.

Reboot the IDE just to be sure everything has been installed correctly.

You are now able to work with Metro M0 Express board and code in Arduino language!

Arduino IDE - Select the board

Plug the board and select the right Port:

Arduino IDE - Select the port

Since the board has native USB support, some interesting libraries you can work with are:

  1. Keyboard Arduino library
  2. Mouse Arduino library

Conclusion

Section titled “Conclusion”

The journey with Adafruit world is at the very beginning. There will be lots of interesting articles in the future!

Documentation

Section titled “Documentation”

Adafruit Products:

Useful links: