NVIC_SetPriority (SysTick_IRQn, (1UL << __NVIC_PRIO_BITS) - 1); SysTick->VAL = 0UL; SysTick->CTRL = (1<<2) |(1<<1) | 1;//配置时钟源,使能定时器,开启中断 return (0UL); } void TickInterruptDelay(__IO u32 nTime) { TimingDelay = nTime; while(TimingDelay != 0); } vo...
return (1UL); /* 无法重新加载值*/ } SysTick->LOAD = (uint32_t)(ticks - 1UL); /* 设置重载寄存器 */ /* 设置Systick中断的优先级 */ NVIC_SetPriority (SysTick_IRQn, (1UL << __NVIC_PRIO_BITS) - 1UL); SysTick->VAL = 0UL; /* 清空SysTick当前值 */ /...
大于该值返回错误 { return (1); } SysTick->LOAD = (uint32_t)(ticks - 1);//计数到0，ticks值应减1 NVIC_SetPriority (SysTick_IRQn, (1UL << __NVIC_PRIO_BITS) - 1); SysTick->VAL = 0UL; SysTick->CTRL = (1<<2) |(1<<1) ...
__STATIC_INLINE void NVIC_SetPriority(IRQn_Type IRQn, uint32_t priority){if ((int32_t)IRQn < 0) {SCB->SHP[(((uint32_t)(int32_t)IRQn) & 0xFUL)-4UL] =(uint8_t)((priority << (8 - __NVIC_PRIO_BITS)) & (uint32_t)0xFFUL);}else {NVIC->IP[((uint32_t)(int32_t)IRQn...
NVIC_SetPriority(SysTick_IRQn, (1UL<<__NVIC_PRIO_BITS)-1UL); // 设置当前数值寄存器 SysTick->VAL=0UL; // 设置系统定时器的时钟源为 AHBCLK=180M // 使能系统定时器中断 // 使能定时器 SysTick->CTRL=SysTick_CTRL_CLKSOURCE_Msk|
15 SysTick->VAL = 0UL; 16 17 // 设置系统定时器的时钟源为 AHBCLK=168M 18 // 使能系统定时器中断 19 // 使能定时器 20 SysTick->CTRL = SysTick_CTRL_CLKSOURCE_Msk | 21 SysTick_CTRL_TICKINT_Msk | 22 SysTick_CTRL_ENABLE_Msk; ...
SysTick->VAL = 0; //写当前值寄存器使其清零 SysTick->CTRL |= (1<<0); //启动定时器,选择半系统时钟 while(!(SysTick->CTRL & 0x10000)); //循环查询,等待定时时间到 SysTick->CTRL &= ~(1<<0); //关闭定时器 } 在程序中,通过“while(!(SysTick ->CTRL & 0x10000));”这句来等待定...
return (0UL); } 第2024 行,函数的形参用于配置滴答定时器LOAD寄存器的数值,由于滴答定时器是一个递减计数器,启动后是将LOAD寄存器的数值赋给VAL寄存器,然后VAL寄存器做递减操作,等递减到 0 的时候重新加载LOAD寄存器的数值继续做递减操作。函数的形参表示内核时钟多少个周期后触发一次 Systick 定时中断,比如形参配置...
11 // 设置中断优先级12 NVIC_SetPriority (SysTick_IRQn, (1UL << __NVIC_PRIO_BITS) - 1UL);13 14 // 设置当前数值寄存器15 SysTick->VAL = 0UL;16 17 // 设置系统定时器的时钟源为AHBCLK=180M18 // 使能系统定时器中断19 // 使能定时器20 SysTick->CTRL = SysTick_CTRL_CLKSOURCE_Msk |...
- 1UL); /* set Priority for Systick Interrupt */ SysTick->VAL = 0UL; /* Load the SysTick Counter Value */ SysTick->CTRL = SysTick_CTRL_CLKSOURCE_Msk | SysTick_CTRL_TICKINT_Msk | SysTick_CTRL_ENABLE_Msk; /* Enable SysTick IRQ and SysTick Timer */ return (0UL); /* Functio...