restructuring

F3:F303/blink/blink.c

@@ -0,0 +1,51 @@
+/*
+ * systick_blink.c
+ *
+ * Copyright 2017 Edward V. Emelianoff <eddy@sao.ru, edward.emelianoff@gmail.com>
+ *
+ * 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);
+        }
+    }
+}