SX1509 I/O Expander Breakout Hookup Guide
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Installing the SparkFun SX1509 Arduino Library
Now that you've got the hardware all mostly figured out, it's time to start programming! To help make using the SX1509 as painless as possible, we've written an Arduino library to help interface with it. Open the Arduino Library Manager and search for SparkFun SX1509. You can also manually install the SparkFun SX1509 Arduino Library from the GitHub repository by clicking on the button below to download the latest version of the library.
For help installing the library, check out our Installing an Arduino Library tutorial. If you downloaded the library as a ZIP, you can use Arduino's Sketch > Include Library > Add .ZIP Library tool to automatically add it to your Arduino sketchbook.
The SparkFun SX1509 Arduino library includes all sorts of examples, which demonstrate specific features of the I/O expander. Navigate to File > Examples > SparkFun SX1509 IO Expander to check them out.
Quickly, we'll walk you through a few quick examples that show off the I/O expander's range of features.