orbit assistant

A portable personal assistance built using the TI Tiva and Orbit Booster Pack. Made for our SE101 final project.

See it in action here!

By Aiden Benner and Lawrence Pan

Features

• Display current time
• Display current weather depending on your location
• Reddit client
• Email client (read and reply to emails)
• Virtual keyboard
• Personal settings

How does it work?

1. Two components: Raspberry PI and Ti Tiva.
2. A Python server that runs on the Raspberry PI listens to the Serial port
3. Ti Tiva prints events to Serial to request for information. eg. GET_WEATHER:CA:Waterloo
4. The Python server extracts the event_name and the options.
5. Depending on the two parameters mentioned above, the server does a certain series of operations.
6. If it is a GET event, python server will fetch data from the internet then send it back to Ti Tiva as a JSON string.
7. If it is an event with side effects (eg. SET_NAME, SEND_MAIL), the python server will simply return a status code.

State management

• Inspired by the redux library.
• Single source of truth, read-only state
• See state.cpp

Possible improvements

• Support asynchronous operations
  • Unfortunately, the board we are using does not support multi-threading. However, if we have a more powerful board, here is what we will do.
  • We supply an unique ID to the event we dispatch from Ti Tiva and then add the ID to a vector. eg. GET_WEATHER:1fe3:CA:WATERLOO
  • We dispatch a python asyncio coroutine to fetch the information
  • When we send the JSON string back to the Ti Tiva, we supply the ID as one of the fields.
  • On Ti Tiva, we have one thread constantly polling on the serial.
  • When it receives JSON, depending on the ID, we update the corresponding state variable (eg. g_weather)

Challenges we ran into

• Parsing JSON
  • Hydrating JSON string on an embedded device is a little harder than just JSON.parse in JavaScript
• Working with the OLED library