Interactive Board Visualisation

See an EoS Program Run
Without Hardware

An illustrative, in-browser visualisation of small EoS programs: toggle GPIO pins and watch console output. It does not compile or execute EoS. To boot the real kernel without hardware, use ebuild sim on QEMU (see Getting Started).

View EoSim on GitHub Documentation

PCB Signal TracesSTM32F4 Discovery

OscilloscopeLED Blink

Target Board

Program

STM32F4 Discovery

STM32F407VGT6

ARM Cortex-M4

Clock

168 MHz

Flash

1 MB

RAM

192 KB

GPIO Pins

Click OUTPUT pins to toggle

led_blink.c

Toggles an output pin at 1 Hz

// EoS LED Blink — written against the real EoS HAL (eos/hal.h)
#include <eos/hal.h>
#include <stdio.h>

int main(void) {
    eos_hal_init();
    eos_gpio_config_t led = { .pin = 0, .mode = EOS_GPIO_OUTPUT };
    eos_gpio_init(&led);
    printf("LED blink started\n");

    while (1) {
        eos_gpio_write(0, true);
        printf("PIN_0 -> HIGH\n");
        eos_delay_ms(500);

        eos_gpio_write(0, false);
        printf("PIN_0 -> LOW\n");
        eos_delay_ms(500);
    }
}

UART / Serial Output

IDLE

Press Run to start simulation…

83 Supported Boards

STM32, ESP32, Raspberry Pi Pico, RISC-V, nRF52, i.MX RT and more, shown as board views. This is a visualisation, not an emulator.

Real Kernel on QEMU

For real execution, ebuild sim builds your code with the EoS kernel and boots it on QEMU's Cortex-M3 machine.

HIL Bridge Support

Connect EoSim to real hardware via the HIL bridge for hardware-in-the-loop testing workflows.

See an EoS Program RunWithout Hardware

See an EoS Program Run
Without Hardware