PaPiRus e-Ink display
Use a low-power display to read books, display graphics and more…
Pi Supply ( https://uk.pi-supply.com) has designed a range of cheap e-ink screens that are easy to install and have the puntastic moniker PaPiRus. A number of different screen sizes are available, ranging from a dinky 1.44-inch (suitable for Pi Zero projects) to a large 2.7-inch (264x176). It’s worth noting that the 2.7-inch model overshoots the edge of the HAT board, and hence the edge of the Pi by a few mm. So the whole shebang won’t fit in a standard case. It will sit on top of a Pibow Coupé case or other open case, though.
All models are equipped with a battery-backed
RTC (real time clock). There are also four input buttons that sit along the edge of the board.
Constructing the kit might be a tiny bit fiddly, depending on how fat your fingers are. For full instructions see https://learn.pi-supply.com/make/ papirus-assembly-tips-and-gotchas. The first step is easy: connect the screen to the board with the ribbon cable. Just make sure all the connectors line up nicely. The next step is not so easy, but is also optional. It involves soldering a springy pin, known as a pogo pin, on to one of two positions on the board (depending on which model of Pi you’re using, the RUN pin on the 3 B has moved to the other side of the board, so use CN15 in this case, and CN13 for all other Pis). If you don’t do this, you won’t be able to use the wake-on-alarm facility provided by the RTC, but all e-ink-related functions will work as normal. Next, push the buttons onto the board and solder their feet from the reverse. They’ll work if you don’t solder them, but they’ll rattle around and possibly jump off. They are small enough that you could easily lose them forever in this event. Fix the HAT and screen on to the GPIO pins, place the standoffs in between the board and the Pi, and screw them in place.
It’s software time
Now we need to install the high-level software. Full instructions can be found at https://github.com/ PiSupply/PaPiRus you can choose between an easy
curl -sSL https://pisupp.ly/papiruscode | sudo bash one liner, or you can do things manually. As of press time there’s an issue installing the dateutil python module, so if you see errors you can rectify them with
$ sudo pip3 install dateutil and then rerun the set up script. If the SPI and I2C buses weren’t enabled already, you’ll need to reboot your Pi before you can start playing with it.
Run sudo papirus-config and set the appropriate screen size before you do anything else. These screens are quite fragile, but they also behave like they’re broken (displaying an odd barcode pattern) if you don’t set the dimensions correctly. Now quit the configuration utility and run sudo papirus-test . If you see errors about missing /dev/epd/version, then the paper driver hasn’t loaded. Aside from broken hardware, this could be because the HAT isn’t sitting flush on the GPIO pins, which is an easy fix. It could also be because of insufficient power. You can try reloading the driver with
sudo systemctl start epd-fuse . Hopefully you figure it out. When you do you’ll find a whole bunch more examples by typing papirus- and pressing Tab. Using handy Python APIs, PaPiRus can display text, graphics, or a combination of both.