/* * systick_blink.c * * Copyright 2017 Edward V. Emelianoff * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, * MA 02110-1301, USA. */ #include "stm32f3.h" static volatile uint32_t blink_ctr = 0; void sys_tick_handler(void){ ++blink_ctr; } static void gpio_setup(void){ RCC->AHBENR |= RCC_AHBENR_GPIOAEN | RCC_AHBENR_GPIOBEN; GPIOA->MODER = GPIO_MODER_MODER8_O | GPIO_MODER_MODER6_O; GPIOA->ODR = 0; GPIOB->MODER = GPIO_MODER_MODER0_O | GPIO_MODER_MODER1_O; GPIOB->ODR = 3; } int main(void){ if(!StartHSE()) StartHSI(); SysTick_Config((uint32_t)72000); // 1ms gpio_setup(); //while(blink_ctr < 9); uint32_t ctr = blink_ctr; while(1){ if(blink_ctr - ctr > 499){ ctr = blink_ctr; pin_toggle(GPIOA, 1<<8|1<<6); pin_toggle(GPIOB, 3); } } }