LCD Display Mayfly

Most 16×2 LCD displays require 5v, but there are some that’ll work at 3.3v if you shop around. You could also use a 5v display with the Mayfly because you can use the 5v boost circuit to power it, but remember that you’ll have to do some logic-level shifting on the data pins. You could accomplish that by putting one of these inline between the Mayfly and the 5v display: https://www.sparkfun.com/products/12009

But I really prefer to use one of these OLED displays: https://www.amazon.com/Grove-128×64-Board-Arduino-Raspberry/dp/B01D5GLDJ2

It uses the same SSD1306 library as the Adafruit display you posted, but it’s got twice as many pixels since it’s 128×64 instead of 128×32, and it’s cheaper. And the big advantage is that it doesn’t require the separate RST pin like what’s on the Adafruit version, so instead of 5 pins (PWR, GND, SDA, SCL, and RST), it only requires 4 pins, so it has a standard Grove connector on the display board. All you have to do is connect the display directly to the I2C port on the Mayfly using a Grove cable (not included with the display when you buy it from SwitchDoc Labs on Amazon), load a sketch, and the Mayfly prints right on the display. I can post a sample sketch if you’d like.

Hi Shannon,
I am interested in a sample sketch of how to write the info on the display.

First you have to download the Arduino library for the SSD1306 by following the link on the Amazon listing to the manufacturer’s site which will then let you get to their own product listing: http://store.switchdoc.com/grove-128×64-i2c-oled-board-for-arduino-and-raspberry-pi/
On that page there’s a link to their library on Github:
https://github.com/switchdoclabs/SDL_Arduino_SSD1306
Install that library and run the example sketch that comes with it. Simply connect the OLED display to the I2C port of the Mayfly and the demo text and graphics will be displayed on the screen.