STM32 GPIO: Pins, Modes, and Configuration

GPIO is where almost every STM32 project starts. Before UART, timers, or any other peripheral comes into the picture, a project usually begins with a pin being configured to read a button or drive an LED. This page is a starting point for everything related to STM32 GPIO, pulled together in one place.

If you are new to STM32 GPIO, start with the STM32 GPIO Complete Guide, which covers ports and pins, how a pin works internally, the four GPIO modes, registers, and a working LED and button example. From there, each topic has its own dedicated guide: GPIO modes, push-pull versus open-drain outputs, pull-up and pull-down resistors, output speed, GPIO registers, and alternate function pins.

These guides are written to be worked through in order, but each one also stands on its own, so feel free to jump straight to whichever topic you are stuck on.