basicGpio.c

#include “hal.h”
#include “ch.h”

int main(void) {
  halInit(); // initializes hardware abstraction layer
  chSysInit(); // initializes ChibiOS kernel
  // configures GPIOC pin 1 as output pushpull
  palSetPadMode(GPIOC, 1, PAL_MODE_OUTPUT_PUSHPULL);
  while(1) {
    palSetPad(GPIOC, 1); // sets GPIOC 1 high
    chThdSleepMilliseconds(500); // sleeps for 500ms
    palClearPad(GPIOC, 1); // sets GPIOC 1 low
    chThdSleepMilliseconds(500); // sleeps for 500ms
  }
}