stm32 系統(tǒng)嘀嗒(SysTick) 定時器

/* ################################## SysTick function ############################################ */

#if (!defined (__Vendor_SysTickConfig)) || (__Vendor_SysTickConfig == 0)

/* SysTick constants */

#define SYSTICK_ENABLE 0 /* Config-Bit to start or stop the SysTick Timer */

#define SYSTICK_TICKINT 1 /* Config-Bit to enable or disable the SysTick interrupt */

#define SYSTICK_CLKSOURCE 2 /* Clocksource has the offset 2 in SysTick Control and Status Register */

#define SYSTICK_MAXCOUNT ((1<<24) -1) /* SysTick MaxCount */

/**

* @brief Initialize and start the SysTick counter and its interrupt.

*

* @param uint32_t ticks is the number of ticks between two interrupts

* @return none

*

* Initialise the system tick timer and its interrupt and start the

* system tick timer / counter in free running mode to generate

* periodical interrupts.

*/

static __INLINE uint32_t SysTick_Config(uint32_t ticks)

{

if (ticks > SYSTICK_MAXCOUNT) return (1); /* Reload value impossible */

SysTick->LOAD = (ticks & SYSTICK_MAXCOUNT) - 1; /* set reload register */

NVIC_SetPriority (SysTick_IRQn, (1<<__NVIC_PRIO_BITS) - 1); /* set Priority for Cortex-M0 System Interrupts */

SysTick->VAL = (0x00); /* Load the SysTick Counter Value */

SysTick->CTRL = (1 << SYSTICK_CLKSOURCE) | (1<

return (0); /* Function successful */

}

#endif

老的庫文件的是6個函數(shù)

1.void SysTick_CLKSourceConfig(uint32_t SysTick_CLKSource)

下面的這幾個的功能都已經(jīng)被SysTick_Config() 所替代

2.voidSysTick_SetReload(void)

3.voidSysTick_CounterCmd(void)

4.voidSysTick_ITConfig(void)

5.voidSysTick_GetCounter(void)

6.voidSysTick_GetFlagStatus(void)