The EnviroDIY™ Mayfly Data Logger is an Arduino-framework microcontroller board designed specifically for environmental Internet of Things (IoT) applications with the goal to facilitate professional-quality, do-it-yourself (DIY) environmental science and monitoring.
This EnviroDIY_Mayfly_Logger Github repository provides hardware design files and example code sketches, the EnviroDIY community provides support via project posts and forums, and the Mayfly Logger board is available for purchase on on Amazon for user convenience.
- ATmega1284p processor
- 128kB program (flash) memory, 16kB RAM
- 2 UART, 1 I2C, 1 SPI connection
- 32 total I/O pins
- 3.3V, 8MHz operating frequency
- Integrated 6V solar lipo battery charger
- Precise real time clock (RTC, DS3231) with separate power supply
- Auxillary 16 bit ADC (TI ADS1115)
- FTDI chip for USB communication
- microSD memory card socket
- XBee radio/wifi/cellular module socket
- 6 Grove connectors with access to I2C, auxillary ADC, and digital pins
- 0.5A switchable power supply for sensors at either 3.3V or 5V
- On-board power switch
- Two controllable LED's, red and green
- One programmable push-button
- Option of using external power supply at 5-12V
| Pin Number[s] | Function | Access | Notes |
|---|---|---|---|
| D0/D1 | Serial Rx/Tx (UART) | Connected to FTDI for USB programming | Also accessible via programming port, 20 pin header, and XBee socket via SJ8/9 |
| D2/D3 | Serial1 Rx/Tx (UART) | XBee socket Din/Dout (pins 2/3) | Also accessible via 20 pin header, can be disconnected from XBee socket via SJ8/9 |
| D19 | XBee CTS | XBee socket CTS (pin 12) | Also accessible via 20 pin header |
| D20 | XBee RTS | XBee socket RTS (pin 16) | Also accessible via 20 pin header |
| D23 | XBee DTR | XBee socket DTR (pin 9) | Also accessible via 20 pin header |
| A5=D29* | XBee Assoc or RI | XBee socket Assoc or RI (pin 15 or 20) | Not connected to XBee socket by default, use SJ7 to connect; Also accessible via 20 pin header |
| D16/D17 | I2C SCL/SDA ("Wire") | Grove connector | Also accessible via 20 pin header |
| D13/D14/D15 | SPI MOSI/MISO/SCK | microSD card slot & SPI header | |
| D12 | microSD chip select | microSD card slot & SPI header | |
| D18 | SD card detect OR RTC 32KHz | 20 pin header | Not connected to either SD or RTC by default, use SJ6 for RTC or SJ10 for SD, do not use both |
| A7=D31 or D10 | RTC Interrupt | 20 pin header | A7 is connected to RTC interrupt by default; Use SJ1 to disconnect A7 and/or to connect D10 |
| D22 | Switched power/LED4 | Switched power on all Grove ports | Pin is not directly accessible, only switched power; Cut SJ3 to disconnect LED4 (red) |
| D21 | user push button | 20 pin header | Cut SJ to disconnect button |
| D8 | LED1 (green) | 20 pin header | |
| D9 | LED2 (red) | 20 pin header | |
| A6=D30 | Battery measurement | None | Connected via voltage divider - for v0.4 and newer, use multiplier of 1.27; for v0.3 and older, use multiplier of 1.47 |
| D4-7, D10-11 | General Purpose I/O | Grove connector; 20 pin header | |
| AA0-AA3 | Auxilliary ADC | Grove connector; 20 pin header | Connected to Auxillary adc (TI ADS1115), not to Mayfly analog pins |
| Number | Function | Default Connection |
|---|---|---|
| SJ1 | Connect to interrupt from RTC | Pin A7 connected to RTC interrupt |
| SJ2 | Disconnect D21 from user button | Pin D21 is connected to button (closed) |
| SJ3 | Disconnect D22 from LED3 | Pin D22 is connected to LED3 (closed) |
| SJ4 | Disconnect LED4 from solar | LED4 indicates solar charging status (closed) |
| SJ5* | 5V Boost enable | Boost enabled |
| SJ6** | Connect D18 to RTC RST/32kHz | Not connected (open) |
| SJ7 | Pin A5 to XBee ASSOC or RI | Not connected (all pads open) |
| SJ8 | XBee Din to TX0/TX1 | XBee Din connected to TX1 |
| SJ9 | XBee Dout to RX0/RX1 | XBee Dout connected to RX1 |
| SJ10** | Connect D18 to SD card detect | Not connected (open) |
| SJ11 | USB FTDI programming enable | FTDI enabled (closed) |
| SJ12 | D10 external pull-up | D10 (INT2) is not pulled up externally (open) |
* SJ5 has been removed in versions newer than v0.4 ** SJ6 and SJ10 should not both be closed at the same time
Mayfly Data Logger can be programmed using standard Aruduino code and community libraries via the Arduino Integrated Development Environment (IDE) software or the more powerful PlatformIO extensions for Visual Studio Code or Atom.
To use the Mayfly with the Arduino IDE you must add "EnviroDIY ATmega Boards" using the Tools > Board > Boards Manager as described in the Mayfly Data Logger Software post
No addition set-up is required to use the PlatformIO. The proper enviroment settings for the Mayfly in a platformio.ini file are:
[env:mayfly]
platform = atmelavr
board = mayfly
framework = arduino- Read the Getting Started With the Mayfly Data Logger page on the EnviroDIY community website for guidance for beginners with the Mayfly, sensor station maintence, and data management.
- Make use of the The EnviroDIY Mayfly Data l=Logger Forum to ask and answer questions about the Mayfly
- Learn Mayfly basics following our Mayfly Data Logger Software post and running the example and workshop code sketches, using the Arduino IDE (from File > Sketchbook), from our EnviroDIY_Mayfly_Logger > examples or EnviroDIY_Mayfly_Logger > workshop folders.
- Advance your capabilities to deploy solar-powered environmental monitoring stations with our LearnEnviroDIY tutorial
- Utilize the ModularSensors code library and other EnviroDIY libraries on GitHub for datalogging built around the Mayfly
- Find and attend a training workshop for do-it-yourself environmental monitoring built around the Mayfly by contacting the Stroud Water Research Center's citizen science outreach or education departments.
We share our EnviroDIY Mayfly logger hardware design files and documentation in this repository's Hardware Design Files pages and Documentation pages.
Software sketches and code are released under the BSD 3-Clause License -- See LICENSE.md file for details.
Documentation is licensed as Creative Commons Attribution-ShareAlike 4.0 (CC-BY-SA) copyright.
Hardware designs shared are released, unless otherwise indicated, under the CERN Open Hardware License 1.2 (CERN_OHL).
EnviroDIY™ is presented by the Stroud Water Research Center, with contributions from a community of enthusiasts sharing do-it-yourself ideas for environmental science and monitoring.
Shannon Hicks is the primary developer of the EnviroDIY Mayfly Data Logger hardware, with input from many other contributors.
The Mayfly was developed based on the SODAQ Mbili board hardware and the SODAQ Mbili bootloader software, designed by Gregory Knauff (GKNFF).
This project has benefited from the support from the following funders:
- William Penn Foundation
- US Environmental Protection Agency (EPA)
- National Science Foundation, awards EAR-0724971, EAR-1331856, ACI-1339834
- Stroud Water Research Center endowment