Overview

epaper_featherwing_front.jpg
Monochrome ePaper display running the quote display sketch

Build this quote display using the Adafruit HUZZAH32 Feather and ePaper FeatherWing. Add a LiPo battery and you have a portable quote display.

The great thing about ePaper displays is they keep their display even when power is disconnected. Combine that with the HUZZAH 32 Feather, which can power itself off and wake up at a specified interval, and you have a great symbiotic relationship. A battery powered ePaper display and HUZZAH Feather can continuously display an image for weeks and even months, depending on the battery size and how frequently the HUZZAH powers up to update the display. 

However, there are a few shortcomings in this relationship. An ePaper display is limited to black and white (and red for some ePaper displays), and it can not display fast moving graphics like those used in games and videos, since the refresh rate can be several seconds to display a static image. So ePaper displays work best with static images that update infrequently. This quote display is a great use of an ePaper display with its static image.

Another shortcoming with an ePaper display is that it requires a memory area for drawing text and graphics before it is shown on the display. With an Adafruit 2.13 ePaper display, this will take 7.6 KB of memory (250 x 122 pixels x 2 colors), leaving less memory available for your sketch to run in.  Also, the larger the display, the more memory needed, making large ePaper displays impracticable for most microcontrollers.

Fortunately, Adafruit has come up with an answer to this shortcoming. By adding display memory to the ePaper Featherwing, graphics memory is offloaded from the microcontroller to the display module, making more memory available to your sketch.

Parts

Building the quote display is actually very easy and requires just 3 parts: an ePaper FeatherWing display, a HUZZAH32 Feather and a battery for portable use. Pick one of the 2 ePaper FeatherWings Adafruit currently offers: a monochrome 2.13" display and a tri-color 2.13" display.

There are also a couple of choices of HUZZAH32 Feathers. If you want a quick, no solder project, save some time and go with the pre-soldered version. If you don't mind soldering and save a little bit of money, go with the loose headers version.

The battery makes this project portable and with the low-power features of both the HUZZAH32 and ePaper display, this display can show quotes for weeks or even months on a single charge. The length of time will depend on the size of the battery and how often the HUZZAH32 wakes up to show a new quote.

If you are interested in ePaper displays for other projects, check out the entire line of Adafruit's ePaper displays.

Adafruit 2.13" Tri-Color eInk / ePaper Display FeatherWing

PRODUCT ID: 4128
Easy e-paper finally comes to your Feather, with this breakout that's designed to make it a breeze to add a tri-color eInk display. Chances are you've seen one of those...
$24.95
IN STOCK

Adafruit 2.13" Monochrome eInk / ePaper Display FeatherWing

PRODUCT ID: 4195
Easy e-paper finally comes to your Feather, with this breakout that's designed to make it a breeze to add a monochrome eInk display. Chances are you've seen one of those...
OUT OF STOCK

Adafruit HUZZAH32 – ESP32 Feather Board (pre-soldered)

PRODUCT ID: 3591
Aww yeah, it's the Feather you have been waiting for, this time with pre-assembled headers! The HUZZAH32 is our ESP32-based Feather, made with the...
OUT OF STOCK

Lithium Ion Polymer Battery - 3.7v 1200mAh

PRODUCT ID: 258
Lithium ion polymer (also known as 'lipo' or 'lipoly') batteries are thin, light and powerful. The output ranges from 4.2V when completely charged to 3.7V. This battery...
$9.95
IN STOCK
This guide was first published on Apr 19, 2019. It was last updated on Apr 19, 2019. This page (Overview) was last updated on Sep 17, 2019.