單片機學習筆記————51單片機實現兩片聯級74HC595依次逐個點亮LED之後，再依次逐個熄滅LED的跑馬燈程序

一、使用proteus繪製簡單的電路圖，用於後續仿真

 

二、編寫程序

/********************************************************************************************************************
----	@Project:	LED-74HC595
----	@File:	main.c
----	@Edit:	ZHQ
----	@Version:	V1.0
----	@CreationTime:	20200525
----	@ModifiedTime:	20200525
----	@Description:	第1個至第8個LED燈，先依次逐個亮，再依次逐個滅。第9至第16個LED燈一直滅。
----	單片機：AT89C52
********************************************************************************************************************/
#include "reg52.h"
/*——————宏定義——————*/
#define FOSC 11059200L
#define T1MS (65536-FOSC/12/1000)   /*1ms timer calculation method in 12Tmode*/

#define const_time_level_01_08  400   


/*——————變量函數定義及聲明——————*/
/*定義74HC595*/
sbit Hc595_Sh = P2^3;
sbit Hc595_St = P2^4;
sbit Hc595_Ds = P2^5;

unsigned char ucLED1 = 0;   /*代表16個燈的亮滅狀態，0代表滅，1代表亮*/
unsigned char ucLED2 = 0;
unsigned char ucLED3 = 0;
unsigned char ucLED4 = 0;
unsigned char ucLED5 = 0;
unsigned char ucLED6 = 0;
unsigned char ucLED7 = 0;
unsigned char ucLED8 = 0;
unsigned char ucLED9 = 0;
unsigned char ucLED10 = 0;
unsigned char ucLED11 = 0;
unsigned char ucLED12 = 0;
unsigned char ucLED13 = 0;
unsigned char ucLED14 = 0;
unsigned char ucLED15 = 0;
unsigned char ucLED16 = 0;


unsigned char ucLed_update = 0;  /*刷新變量。每次更改LED燈的狀態都要更新一次。*/

unsigned char ucLedStep_01_08 = 0; /*第1個至第8個LED跑馬燈的步驟變量*/
unsigned int  uiTimeCnt_01_08 = 0; /*第1個至第8個LED跑馬燈的統計定時中斷次數的延時計數器*/

unsigned char ucLedStatus16_09 = 0;   /*代表底層74HC595輸出狀態的中間變量*/
unsigned char ucLedStatus08_01 = 0;   /*代表底層74HC595輸出狀態的中間變量*/

/**
* @brief  定時器0初始化函數
* @param  無
* @retval 初始化T0
**/
void Init_T0(void)
{
	TMOD = 0x01;                    /*set timer0 as mode1 (16-bit)*/
	TL0 = T1MS;                     /*initial timer0 low byte*/
	TH0 = T1MS >> 8;                /*initial timer0 high byte*/
}
/**
* @brief  外圍初始化函數
* @param  無
* @retval 初始化外圍
**/
void Init_Peripheral(void)
{
	ET0 = 1;/*允許定時中斷*/
	TR0 = 1;/*啓動定時中斷*/
	EA = 1;/*開總中斷*/

}

/**
* @brief  初始化函數
* @param  無
* @retval 初始化單片機
**/
void	Init(void)
{
	Init_T0();
}
/**
* @brief  延時函數
* @param  無
* @retval 無
**/
void Delay_Long(unsigned int uiDelayLong)
{
   unsigned int i;
   unsigned int j;
   for(i=0;i<uiDelayLong;i++)
   {
      for(j=0;j<500;j++)  /*內嵌循環的空指令數量*/
          {
             ; /*一個分號相當於執行一條空語句*/
          }
   }
}
/**
* @brief  延時函數
* @param  無
* @retval 無
**/
void Delay_Short(unsigned int uiDelayShort)
{
   unsigned int i;
   for(i=0;i<uiDelayShort;i++)
   {
		 ; /*一個分號相當於執行一條空語句*/
   }
}

/**
* @brief  595驅動函數
* @param  無
* @retval * 兩個聯級74HC595的工作過程：
* 每個74HC595內部都有一個8位的寄存器，兩個聯級起來就有兩個寄存器。ST引腳就相當於一個刷新
* 信號引腳，當ST引腳產生一個上升沿信號時，就會把寄存器的數值輸出到74HC595的輸出引腳並且鎖存起來，
* DS是數據引腳，SH是把新數據送入寄存器的時鐘信號。也就是說，SH引腳負責把數據送入到寄存器裏，ST引腳
* 負責把寄存器的數據更新輸出到74HC595的輸出引腳上並且鎖存起來。
**/
void HC595_Drive(unsigned char ucLedStatusTemp16_09, unsigned char ucLedStatusTemp08_01)
{
	unsigned char i;
	unsigned char ucTempData;
	Hc595_Sh = 0;
	Hc595_St = 0;	
	
	ucTempData = ucLedStatusTemp16_09;	/*先送高8位*/
	for(i = 0; i < 8; i ++)
	{
		if(ucTempData >= 0x80)
		{
			Hc595_Ds = 1;
		}
		else
		{
			Hc595_Ds = 0;
		}
		Hc595_Sh = 0;	/*SH引腳的上升沿把數據送入寄存器*/
		Delay_Short(15); 
		Hc595_Sh = 1;
		Delay_Short(15); 	
			
		ucTempData = ucTempData <<1;
	}
	ucTempData = ucLedStatusTemp08_01;	/*再先送低8位*/
	for(i = 0; i < 8; i ++)
	{
		if(ucTempData >= 0x80)
		{
			Hc595_Ds = 1;
		}
		else
		{
			Hc595_Ds = 0;
		}
		Hc595_Sh = 0;	/*SH引腳的上升沿把數據送入寄存器*/
		Delay_Short(15); 
		Hc595_Sh = 1;
		Delay_Short(15); 	
			
		ucTempData = ucTempData <<1;
	}
	
	Hc595_St = 0;	/*ST引腳把兩個寄存器的數據更新輸出到74HC595的輸出引腳上並且鎖存起來*/
	Delay_Short(15);
	Hc595_St = 1;
	Delay_Short(15);
	
	Hc595_Sh = 0;	/*拉低，抗干擾就增強*/
	Hc595_St = 0;
	Hc595_Ds = 0;
}
/**
* @brief  LED更新函數
* @param  無
* @retval 
* 把74HC595驅動程序翻譯成類似單片機IO口直接驅動方式的過程。
* 每次更新LED輸出，記得都要把ucLed_update置1表示更新。
**/
void LED_Update()
{
	if(ucLed_update == 1)
	{
		ucLed_update = 0;	/*及時清零，讓它產生只更新一次的效果，避免一直更新。*/
		if(ucLED1 == 1)
		{
			ucLedStatus08_01 = ucLedStatus08_01 | 0x01;
		}
		else
		{
			ucLedStatus08_01 = ucLedStatus08_01 & 0xfe;
		}
		if(ucLED2 == 1)
		{
			ucLedStatus08_01 = ucLedStatus08_01 | 0x02;
		}
		else
		{
			ucLedStatus08_01 = ucLedStatus08_01 & 0xfd;
		}
		if(ucLED3 == 1)
		{
			ucLedStatus08_01 = ucLedStatus08_01 | 0x04;
		}
		else
		{
			ucLedStatus08_01 = ucLedStatus08_01 & 0xfb;
		}
		if(ucLED4 == 1)
		{
			ucLedStatus08_01 = ucLedStatus08_01 | 0x08;
		}
		else
		{
			ucLedStatus08_01 = ucLedStatus08_01 & 0xf7;
		}		
		if(ucLED5 == 1)
		{
			ucLedStatus08_01 = ucLedStatus08_01 | 0x10;
		}
		else
		{
			ucLedStatus08_01 = ucLedStatus08_01 & 0xef;
		}
		if(ucLED6 == 1)
		{
			ucLedStatus08_01 = ucLedStatus08_01 | 0x20;
		}
		else
		{
			ucLedStatus08_01 = ucLedStatus08_01 & 0xdf;
		}
		if(ucLED7 == 1)
		{
			ucLedStatus08_01 = ucLedStatus08_01 | 0x40;
		}
		else
		{
			ucLedStatus08_01 = ucLedStatus08_01 & 0xbf;
		}
		if(ucLED8 == 1)
		{
			ucLedStatus08_01 = ucLedStatus08_01 | 0x80;
		}
		else
		{
			ucLedStatus08_01 = ucLedStatus08_01 & 0x7f;
		}
		if(ucLED9 == 1)
		{
			ucLedStatus16_09 = ucLedStatus16_09 | 0x01;
		}
		else
		{
			ucLedStatus16_09 = ucLedStatus16_09 & 0xfe;
		}
		if(ucLED10 == 1)
		{
			ucLedStatus16_09 = ucLedStatus16_09 | 0x02;
		}
		else
		{
			ucLedStatus16_09 = ucLedStatus16_09 & 0xfd;
		}
		if(ucLED11 == 1)
		{
			ucLedStatus16_09 = ucLedStatus16_09 | 0x04;
		}
		else
		{
			ucLedStatus16_09 = ucLedStatus16_09 & 0xfb;
		}
		if(ucLED12 == 1)
		{
			ucLedStatus16_09 = ucLedStatus16_09 | 0x08;
		}
		else
		{
			ucLedStatus16_09 = ucLedStatus16_09 & 0xf7;
		}		
		if(ucLED13 == 1)
		{
			ucLedStatus16_09 = ucLedStatus16_09 | 0x10;
		}
		else
		{
			ucLedStatus16_09 = ucLedStatus16_09 & 0xef;
		}
		if(ucLED14 == 1)
		{
			ucLedStatus16_09 = ucLedStatus16_09 | 0x20;
		}
		else
		{
			ucLedStatus16_09 = ucLedStatus16_09 & 0xdf;
		}
		if(ucLED15 == 1)
		{
			ucLedStatus16_09 = ucLedStatus16_09 | 0x40;
		}
		else
		{
			ucLedStatus16_09 = ucLedStatus16_09 & 0xbf;
		}
		if(ucLED16 == 1)
		{
			ucLedStatus16_09 = ucLedStatus16_09 | 0x80;
		}
		else
		{
			ucLedStatus16_09 = ucLedStatus16_09 & 0x7f;
		}
		HC595_Drive(ucLedStatus16_09, ucLedStatus08_01);
	}
}
/**
* @brief  LED閃爍函數
* @param  無
* @retval 無
**/
void LED_Flicker_01_08(void)
{
	switch(ucLedStep_01_08)
	{
		case 0:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED1 = 1;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 1;
			}
		break;
		case 1:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED2 = 1;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 2;
			}
		break;
		case 2:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED3 = 1;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 3;
			}
		break;
		case 3:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED4 = 1;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 4;
			}
		break;
		case 4:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED5 = 1;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 5;
			}
		break;
		case 5:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED6 = 1;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 6;
			}
		break;
		case 6:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED7 = 1;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 7;
			}
		break;	
		case 7:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED8 = 1;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 8;
			}
		break;
		case 8:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED8 = 0;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 9;
			}
		break;
		case 9:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED7 = 0;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 10;
			}
		break;
		case 10:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED6 = 0;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 11;
			}
		break;
		case 11:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED5 = 0;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 12;
			}
		break;	
		case 12:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED4 = 0;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 13;
			}
		break;
		case 13:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED3 = 0;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 14;
			}
		break;
		case 14:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED2 = 0;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 15;
			}
		break;
		case 15:
			if(uiTimeCnt_01_08 >= const_time_level_01_08)
			{
				uiTimeCnt_01_08 = 0;	/*時間計數器清零*/
				
				ucLED1 = 0;	
				
				ucLed_update = 1;  /*更新顯示*/
				ucLedStep_01_08 = 0;
			}
		break;				
	}
}
/**
* @brief  定時器0中斷函數
* @param  無
* @retval 無
**/
void ISR_T0(void)	interrupt 1
{
	TF0 = 0;  /*清除中斷標誌*/
  TR0 = 0; /*關中斷*/
	
	if(uiTimeCnt_01_08 < 0xffff)	/*設定這個條件，防止uiTimeCnt超範圍。*/
	{
		uiTimeCnt_01_08 ++;		
	}
	
	TL0 = T1MS;                     /*initial timer0 low byte*/
	TH0 = T1MS >> 8;                /*initial timer0 high byte*/
  TR0 = 1; /*開中斷*/	
}

/*——————主函數——————*/
/**
* @brief  主函數
* @param  無
* @retval 實現LED燈閃爍
**/
void main()
{
	/*單片機初始化*/
	Init();
	/*延時，延時時間一般是0.3秒到2秒之間，等待外圍芯片和模塊上電穩定*/
	Delay_Long(100);
	/*單片機外圍初始化*/	
	Init_Peripheral();
	while(1)
	{
		/*按鍵服務函數*/
		LED_Flicker_01_08();
		/*LED更新函數*/
		LED_Update(); 
	}
}

三、仿真實現