The LCD display with an I2C backpack works well in Trinket projects as an informational display. It only requires two of the five Trinket pins.
Sensor monitoring is very common for Internet of Things (IoT) projects. This project can be placed in a very small enclosure and used anywhere sensing is needed. The code and concepts may be used in a number of your own projects.
To maximize the functionality of software on Trinket, new libraries need to be installed. See the All About Arduino Libraries tutorial for details on how to download and install thee liquidcrystal library.
- The Arduino internal Wire library for I2C communications
- The Adafruit_LiquidCrystal library
No library is needed for the ultrasonic sensor.