A couple of years ago I saw that a store sold Kobo eInk readers relativly cheap and a quick google showed that it was possible to root them and do what you wanted, so I bought one, and rooted it.

Unfortunately there were no ready made scripts or programs to display weather information on the screen so I made my own.

The first version

At this time I used Domoticz to control lights and collect sensor data from my house so the solution was to write a python-script that would use the API from yr.no together with the outdoor and indoor temperatures i measured myself.

I created a simple “template” SVG file that the Python script used as a base and inserted the correct icons for upcoming weather and temperatures. The complete SVG was converted to a PNG and then converted again to a raw 1-bit image that was uploaded to the Kobo reader and displayed by feeding it to the built in binary pickle.

The result looked quite basic but it was easy to read.

The second version

I switched from Domoticz to HomeAssistant in 2017 and I needed to rewrite the scripts to fetch the local data from HASS instead of Domoticz but that was boring so it took quite a while.

A bit prettier

When I got around to it I decided to to a total rewrite, use Javascript instead of Python and make it look better, without much effort. The solution was to create a dashboard in HASS that looked good in the right proportions. The built in web-browser in the Kobo didn’t cut it tho so I still needed to create a raw 1-bit image to display. That was solved by periodically running a headless chrome instance that one every five minutes loads the dashboard and takes a screenshot. That screenshot is then cropped and converted to the 1-bit raw file and uploaded and displayed on the Kobo.

Other “useful” stuff.

The new version also enabled interaction via the front button. Pressing it allows the viewer to cycle through a set of predefined “pages”, i.e. images. So instead of just having a single page it now can show the pain page (displayed above), temperature and moisture details around the house and other useful stuff.

Try it yourself

If you’re brave, you can download it and try it yourself here: https://github.com/the-louie/kobo-yr2 .