56 lines
1.0 KiB
C
56 lines
1.0 KiB
C
//SYSCLK 初始化及延时函数
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#include "delay.h"
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static uint32_t fac_us = 0; //us 延时倍乘数
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/**
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* @brief 初始化延迟函数
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* @param SYSCLK: 系统时钟频率
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*/
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void SYSCLK_Init(uint16_t SYSCLK)
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{
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HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);
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fac_us = SYSCLK;
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}
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/**
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* @brief us 延迟函数
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* @param nus: us 数，不可超过 1000
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*/
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void Delay_us(uint32_t nus)
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{
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uint32_t ticks, told, tnow;
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uint32_t tcnt = 0;
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uint32_t reload = SysTick->LOAD; //LOAD 的值
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ticks = nus * fac_us; //需要的节拍数
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told = SysTick->VAL; //当前计数器值
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while (1)
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{
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tnow = SysTick->VAL;
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if (tnow != told)
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{
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if (tnow < told)
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tcnt += told - tnow;
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else
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tcnt += reload - tnow + told;
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told = tnow;
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if (tcnt >= ticks)
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break;
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}
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};
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}
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/**
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* @brief ms 延迟函数
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* @param nms: ms 数
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*/
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void Delay_ms(uint16_t nms)
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{
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uint32_t i;
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for (i = 0; i < nms; i++)
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Delay_us(1000);
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}
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