hello-world-sysmodule/src/main.cpp

extern "C"
{
#include <3ds.h>
#include "miscdef.h"
#include "MCU/Mcu.h"

	int main()
	{
		mcuInit();
		ledReset();

		while (true) {
			ledStay(0xFF00);
			svcSleepThread(5e8);
			ledStay(0xFF0000);
			svcSleepThread(5e8);
		}
	}
}