/* * This file is part of the libopencm3 project. * * Copyright (C) 2009 Uwe Hermann * Copyright (C) 2011 Fergus Noble * * This library is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this library. If not, see . */ #include #include void gpio_setup(void) { /* Enable GPIOC clock. */ rcc_peripheral_enable_clock(&RCC_AHB1ENR, RCC_AHB1ENR_IOPCEN); /* Set GPIO3 and GPIO4 (in GPIO port C) to 'output push-pull'. */ gpio_mode_setup(GPIOC, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO3 | GPIO4); } int main(void) { int i; gpio_setup(); gpio_set(GPIOC, GPIO3); gpio_clear(GPIOC, GPIO4); /* Blink the LEDs (PC3, PC4) on the board. */ while (1) { /* Using API function gpio_toggle(): */ gpio_toggle(GPIOC, GPIO3); gpio_toggle(GPIOC, GPIO4); for (i = 0; i < 800000; i++) /* Wait a bit. */ __asm__("nop"); } return 0; }