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#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wstrict-aliasing"
#include <stm32f1xx.h>
#pragma GCC diagnostic pop
#include <system_stm32f1xx.h>
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include <unistd.h>
/* Part number: STM32F030F4C6 */
static volatile unsigned int sys_time;
uint32_t get_tick() {
return SysTick->VAL;
}
int main(void) {
/* External crystal: 8MHz */
RCC->CR |= RCC_CR_HSEON;
while (!(RCC->CR&RCC_CR_HSERDY));
/* Sysclk = HCLK = 48MHz */
RCC->CFGR = (RCC->CFGR & (~RCC_CFGR_PLLMULL_Msk & ~RCC_CFGR_SW_Msk & ~RCC_CFGR_PPRE1_Msk & ~RCC_CFGR_PPRE2_Msk & ~RCC_CFGR_HPRE_Msk))
| (10<<RCC_CFGR_PLLMULL_Pos) | RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLSRC | (4<<RCC_CFGR_PPRE1_Pos) | (4<<RCC_CFGR_PPRE2_Pos);
RCC->CR |= RCC_CR_PLLON;
while (!(RCC->CR&RCC_CR_PLLRDY));
/* Switch to PLL */
RCC->CFGR |= (2<<RCC_CFGR_SW_Pos);
//RCC->CFGR = (RCC->CFGR & (~RCC_CFGR_PPRE1_Msk & ~RCC_CFGR_PPRE2_Msk))
// | (4<<RCC_CFGR_PPRE1_Pos) | (4<<RCC_CFGR_PPRE2_Pos);
SystemCoreClockUpdate();
RCC->APB2ENR |= RCC_APB2ENR_IOPAEN | RCC_APB2ENR_IOPBEN | RCC_APB2ENR_IOPCEN;
GPIOA->CRL =
(0<<GPIO_CRL_CNF6_Pos) | (1<<GPIO_CRL_MODE6_Pos) /* PA6 - Channel 1 low side */
| (0<<GPIO_CRL_CNF7_Pos) | (1<<GPIO_CRL_MODE7_Pos); /* PA7 - Channel 2 low side */
GPIOB->CRL =
(0<<GPIO_CRL_CNF0_Pos) | (1<<GPIO_CRL_MODE0_Pos) /* PB0 - Channel 1 high side */
| (0<<GPIO_CRL_CNF1_Pos) | (1<<GPIO_CRL_MODE1_Pos); /* PB1 - Channel 2 high side */
GPIOC->CRH =
(0<<GPIO_CRH_CNF13_Pos) | (1<<GPIO_CRH_MODE13_Pos); /* PC13 - LED */
/* Turn all outputs off */
GPIOA->BRR |= 1<<6 | 1<<7;
GPIOB->BRR |= 1<<0 | 1<<1;
while (42) {
#define FOO 100000
for (int i=0; i<FOO; i++) ;
GPIOA->BRR |= 1<<6 | 1<<7;
GPIOB->BRR |= 1<<0 | 1<<1;
GPIOA->BSRR |= 1<<6;
GPIOB->BSRR |= 1<<1;
for (int i=0; i<FOO; i++) ;
GPIOA->BRR |= 1<<6 | 1<<7;
GPIOB->BRR |= 1<<0 | 1<<1;
GPIOA->BSRR |= 1<<7;
GPIOB->BSRR |= 1<<0;
GPIOC->ODR ^= 1<<13;
}
}
void NMI_Handler(void) {
}
void HardFault_Handler(void) __attribute__((naked));
void HardFault_Handler() {
asm volatile ("bkpt");
}
void SVC_Handler(void) {
}
void PendSV_Handler(void) {
}
void SysTick_Handler(void) {
sys_time++;
}
void _init(void) {
}
void MemManage_Handler(void) __attribute__((naked));
void MemManage_Handler() {
asm volatile ("bkpt");
}
void BusFault_Handler(void) __attribute__((naked));
void BusFault_Handler() {
asm volatile ("bkpt");
}
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