Welcome to the first part in a two part series about using an LCD Character display with Android Things. In this part we’ll collect, partially explain, and wire together the hardware. In the next part we’ll setup the project in Android Studio and write some clever messages to the display.
The Android things I2C API enables you to communicate with I2C devices, such as the PCF8574, using java in an Android project. The PCF8574 is a port expander that lets you connect to peripherals over a relatively high speed serial bus to a controller. This reduces the wire count and pin usage. Common usage includes interfaces to buttons, keypads and displays. We will use the PCF8574 to connect a Raspberry Pi to an LCD Character display.