E-ink display technology has slowly come down in price since its introduction to the market in the early 2000s. For a long time, only manufacturers of ebook readers could buy enough of them in bulk to make the price worthwhile. However, it’s now possible to get decently-sized epaper displays for under $20. So, Joey of Oddly Specific Projects decided to create a DIY ebook reader with all the bells and whistles you’d expect from a commercial product. Just to be clear up front: this is not a kit. The listing is for the (absolutely gorgeous) PCBs, a printed BOM, excellent documentation, and instructions on how to source the parts and build one yourself.
A big key to this project is the availability of e-ink displays for a reasonable price. The recommended display is from GoodDisplay, but is also available from WaveShare for a little bit more. They also have multi-coloured e-ink displays, which are super neat.
Making e-readers available for hackers to play with is a huge step forward in the adoption of the display technology for smaller projects. The OpenBook has a lot more than just the e-reader parts — it has an Adafruit Feather header ready to be populated, as well as debug access to the main SAMD51 ARM microcontroller. This allows it to be hacked to do just about anything you can imagine with an e-ink display. By default, the SAM is running CircuitPython, but also has a powerful C++ library to handle all the interfacing with the e-ink display.
Various different cases are possible. The incredibly detailed documentation has a section devoted to enclosures. The above photo shows a beautiful basswood frame that was laser-cut and assembled as a basic case. Of course, it still allows access to the PCB for hacking, meaning it’s not fully protected. A complete enclosure wouldn’t be too hard to make, based off of the measurements and 3D print data included in the documentation.
Another important part of this project is the ability to display text in almost any language. One of the on-board flash chips (appropriately named the Babel Chip) simply contains the Unifont glyphs for the entire basic multilingual plane of Unicode. Unifont is a GNU project that aims to create a standard font with a glyph for every code point that is a written letter, diacritic, or accent. This project alone is a huge undertaking, and is worth taking a look at. The inclusion of this font allows books to be viewed in hundreds of different languages, which is a really nice touch.
There is a simpler version of this project, also by the same designer, that is called the E-Book Wing PCB. That version is powered entirely by an Adafruit Feather M4 Express. It has a simpler Bill of Materials, and is generally easier to assemble.
I hope that assembled boards will eventually be available to purchase. In the meantime, this author is going to set some time aside this fall to build one!
The OpenBook PCB next to its younger sibling, the E-Book Wing PCB
