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John M. Wargo edited this page May 3, 2020 · 14 revisions

The project is the latest version of the Pi Remind project, a Raspberry Pi-based project for notifying users of upcoming appointments in their Google Calendar.

an enhancement to the Pi Remind HD project enabling it to work with the Remote Notify project.

Multiple Remind projects:

  • Pi Remind
  • Pi Remind Blinkit
  • Pi Remind HD (archived, point to this one)
  • Pi Remind HD Notify

The Pi Remind project connects to a user's Google Calendar, then displays appointment reminders on a Unicorn HAT HD. In this project, the status of the user's Google Calendar is also sent to the Remote Notify device, lighting a LED Red when the user is busy (based on the calendar), Yellow for tentative, and Green for free/available.

Raspberry Pi Appointment Reminder (HD)

I often find myself missing appointments because I'm engrossed in my work or because I've switched to a different computer and can't hear the reminder ping on my work laptop. I created this project to give me a visual reminder, an obnoxious, silent countdown timer I can set on my desk to flash lights at me as a warning before my next meeting starts.

The project uses a network connected Raspberry Pi and a Pimoroni Unicorn HAT HD to flash the reminder. The project was originally built using the Pimoroni Unicorn HAT, and published in Make Magazine (makezine.com): Get a Flashing Meeting Reminder with a Raspberry Pi. For this version, I upgraded the Unicorn HAT to the High Definition (HD) version which will allow me to display much cleaner and more interesting color patterns. The HD version of the Unicorn HAT has 256 LEDs vs the original Unicorn HAT's 64, for much higher pixel resolution.

One of the things I wanted to do in the original project was display the meeting description/subject on the Unicorn HAT. I could have done it, but because of the low pixel resolution of the Unicorn HAT, it would have looked clunky. The Unicorn HAT HD has a higher pixel resolution, so I've added the feature here.

Alerts

The Pi connects to Google Calendar and checks every minute for upcoming appointments then flashes the Unicorn HAT's LEDs for following alerts:

  • White @ 10 minutes until 5 minutes
  • Yellow @ 5 minutes until 2 minutes
  • Multi-color swirl @ 2 minutes

If you're feeling adventurous, you can change the code to use any of the sample patterns included with the Unicorn HAT HD Sample Code. I'm personally a big fan of the star field example, but that's not very useful as an alerting mechanism.

Indicator LED

The project displays a single indicator LED to let you know the app is working. It will illuminate a single LED along the bottom row of the Unicorn HAT and move the LED across the display every time it connects to Google to obtain calendar information. The color of the LED indicates status of the app as well:

  • Blue - The app is connecting to the Google Calendar API
  • Green - The app received data from the Google Calendar API, but there are no pending appointments within the next 10 minutes
  • Red - The app encountered an error connecting to the Google Calendar API
  • White - There is an appointment beginning within 10 minutes
  • Yellow - There is an appointment beginning within the next 5 minutes
  • Orange - There is an appointment beginning within the next 2 minutes

This way, even if you miss the flashing lights, you can glance at the display and still determine if you have an upcoming appointment.

Required Components

For this project, I used the following components: