25 lines
506 B
C
25 lines
506 B
C
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#include "delay.h"
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/*
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@ brief 延时函数
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@ param
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@ return
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@ note 2022-5-23
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*/
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void delay_us(int us)
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{
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uint32_t start, now, delta, reload, us_tick;
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start = SysTick->VAL;
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reload = SysTick->LOAD;
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us_tick = SystemCoreClock / 1000000UL;
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do
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{
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now = SysTick->VAL;
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delta = start > now ? start - now : reload + start - now;
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} while (delta < us_tick * us);
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}
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void delay_ms(int ms)//封装了，不能直接替换，不知道为什么
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{
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rt_thread_mdelay(ms);
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}
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