blink-gpio

Blink GPIO — Simplest EoS Application

Toggles an LED on and off every 500ms. This is the "Hello World" of EoS.

What it demonstrates

• HAL initialization with eos_hal_init()
• GPIO output configuration with eos_gpio_init()
• GPIO write with eos_gpio_write()
• Delay with eos_delay_ms()

Modules used

Module	Header	Functions
HAL	eos/hal.h	eos_hal_init, eos_gpio_init, eos_gpio_write, eos_delay_ms

How to build

# Host build (no hardware needed)
cmake -B build -DEOS_PRODUCT=iot
cmake --build build
./build/blink-gpio

# ARM cross-compile
cmake -B build \
  -DCMAKE_TOOLCHAIN_FILE=../../toolchains/arm-none-eabi.cmake \
  -DEOS_PRODUCT=iot
cmake --build build

Expected output

[blink] Starting LED blink on pin 13
[blink] LED ON
[blink] LED OFF
[blink] LED ON
[blink] LED OFF
...

On real hardware, the LED connected to pin 13 will blink at 1 Hz.

Customization

Change LED_PIN in main.c to match your board's LED pin:

• nRF52840-DK: pin 13 (LED1)
• STM32 Nucleo: pin 5 (LD2)
• Raspberry Pi Pico: pin 25