This small project is based on this article by Anders Holmberg, in which he describes how to call C functions defined in the Pico SDK from Zig. This program only reads the signal input from GPIO 15 on a Raspberry Pi Pico (W) and prints out if GPIO 15 is set or not. I made a personal addition to the build.zig file to get the Pico SDK path environment variable from an .env file.

# .env PICO_SDK_PATH=/path/to/your/pico-sdk

The GPIO 15 pin can be connected an removed to see the output difference in the program.