#define SysTick_CTRL_TICKINT_Pos 1U
#define SysTick_CTRL_TICKINT_Msk (1UL << SysTick_CTRL_TICKINT_Pos)
#define DRV_SYS_TICK_USE_SYS_CLK (SysTick_CTRL_CLKSOURCE_Msk|SysTick_CTRL_ENABLE_Msk)
对系统时钟进行初始化:
drv_sys_tick_init(DRV_SYS_TICK_USE_SYS_CLK | SysTick_CTRL_TICKINT_Msk