(程序未实现功能,不太懂为什么)
bsp_sysytick.c
#include "bsp_systick.h"
#if 0
static __INLINE uint32_t SysTick_Config(uint32_t ticks)
{
//判断tick的值是否大于2^24,如果大于,则不符合规则
if (ticks > SysTick_LOAD_RELOAD_Msk) return (1);
//初始化reload寄存器的值
SysTick->LOAD = (ticks & SysTick_LOAD_RELOAD_Msk) - 1;
//配置中断优先级,配置为15,默认为最低优先级
NVIC_SetPriority (SysTick_IRQn, (1<<__NVIC_PRIO_BITS) - 1);
//初始化counter的值为0
SysTick->VAL = 0;
//配置sysytick的时钟为72M,使能中断,使能systick
SysTick->CTRL = SysTick_CTRL_CLKSOURCE_Msk |
SysTick_CTRL_TICKINT_Msk |
SysTick_CTRL_ENABLE_Msk;
return (0);
}
#endif
void SysTick_Delay_us(uint32_t us)
{
uint32_t i;
SysTick_Config(72);//与系统时钟相关72M