Calendars

Where to find the iCal link for each calendar service, and how to tell them apart.

The display reads iCal feeds, the format every calendar service can share. Add up to eight. At every refresh the drawing service fetches each one fresh on the display’s behalf, merges them, and draws the week.

Finding the link

• Google Calendar: on the web, open the calendar’s settings, scroll to Integrate calendar, and copy the Secret address in iCal format. The public address only works for calendars you have made public.
• Outlook and Microsoft 365: Settings → Calendar → Shared calendars → Publish a calendar, then copy the ICS link.
• iCloud: in the Calendar app, share the calendar as a Public Calendar and copy the webcal:// link. It is pasted as is.
• Nextcloud, Fastmail, Proton and others: look for export, subscribe or share link on the calendar; the link ends in .ics or starts with webcal://.

webcal:// links and Google’s browser links are both understood, so paste whatever you were given.

Telling calendars apart

Every calendar can carry a marker: a circle, square or triangle, filled or hollow, in one of five inks, drawn before each of its events. Three shapes, two fills and five inks are enough to tell eight calendars apart at a glance.

A new calendar has no marker until you choose one. A calendar can also colour the titles of its events instead: easier to read across a room, but each calendar spends a whole ink on it, and titles are black anyway unless you change them, so only four calendars stand out that way.

Keeping your calendars private

The display sends your calendar links to the drawing service at each refresh, the service fetches them, draws the week and answers with the picture. It keeps no copy of the links or the events: there is no database and nothing is written between requests. If you ever want to revoke access, reset the secret address in your calendar service; the display will show a notice until you paste the new one.