一、基本知識

（1）鎖存

鎖存芯片的作用：保存上一狀態值先給他賦值1，【使能端為高】，讓我們要顯示的數值通過，再給他賦值0，【使能端為低】，就可以鎖住數值

（2）電路圖看段選和位選

在BSTV51單片機中 P2^6 這個串口是段選，控制那一個數字的具體顯示，可根據字形表對應輸出 P2^7 是位選，選擇控制要哪一位亮燈

（3）共陽極數碼管與共陰極數碼管

• 共陰極–輸出低電平0，點亮
• 共陽極–輸出高電平點亮
• 共有十個引腳，2個接地GND
  

二、靜態數碼管

• 靜態顯示的連接方式、靜態顯示的優缺點（優點：不需要動態重繪；缺點：占用IO口線多）
• 動態顯示的連接方式（所有位數碼管的段選線并聯在一起，由 位選線控制是哪一位數碼管有效）、動態顯示的優缺點（缺點：需要動態重繪；優點：占用IO口線少）

#include<reg52.h>

sbit DUAN = P2^6;
sbit WEI  = P2^7;



void main()
{
	P0 = 0x7d; // 1111 1110
	DUAN = 1;
	DUAN = 0;

	P0 = 0x00; 
	WEI = 1;
	WEI = 0;

/*	P0 = 0x7c; // 1111 1110
	DUAN = 1;
	DUAN = 0;

	P0 = 0xfd; 
	WEI = 1;
	WEI = 0;	  */
	 
}

三、動態數碼管

用延遲函式

#include<reg52.h>
sbit DUAN = P2^6;
sbit WEI  = P2^7;

void delay(unsigned int xms)
{
	unsigned int i,j;
	for(i=xms;i>0;i--)
		for(j=112;j>0;j--);
}

unsigned code sz[17] = { 0x3f,0x06,0x5b,0x4f,0x66,0x6d,
  						 0x7d,0x07,0x7f,0x6f,0x77,0x7c,
						 0x39,0x5e,0x79,0x71,0x00
};
void main()
{
	while(1)
	{
		P0 = sz[1];		// 數字1
		DUAN = 1;		// 一端上電
		DUAN = 0;		//	 斷開
		P0 = 0xfe;
		WEI  = 1;		//	另一端上高電平
		WEI  = 0;		//	另一端斷開
		delay(200);

		P0 = sz[2];		// 數字2
		DUAN = 1;
		DUAN = 0;
		P0 = 0xfd;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[3];		// 數字3
		DUAN = 1;
		DUAN = 0;
		P0 = 0xfb;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[4];		// 數字4   
		DUAN = 1;
		DUAN = 0;
		P0 = 0xf7;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[5];		// 數字5
		DUAN = 1;
		DUAN = 0;
		P0 = 0xef;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[6];		// 數字6	 
		DUAN = 1;
		DUAN = 0;
		P0 = 0xdf;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[7];		// 數字7
		DUAN = 1;
		DUAN = 0;
		P0 = 0xbf;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[8];		// 數字8
		DUAN = 1;
		DUAN = 0;
		P0 = 0x7f;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[8];		// 數字8
		DUAN = 1;
		DUAN = 0;
		P0 = 0x7f;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[7];		// 數字7
		DUAN = 1;
		DUAN = 0;
		P0 = 0xbf;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[6];		// 數字6	 
		DUAN = 1;
		DUAN = 0;
		P0 = 0xdf;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[5];		// 數字5
		DUAN = 1;
		DUAN = 0;
		P0 = 0xef;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[4];		// 數字4   
		DUAN = 1;
		DUAN = 0;
		P0 = 0xf7;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[3];		// 數字3
		DUAN = 1;
		DUAN = 0;
		P0 = 0xfb;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[2];		// 數字2
		DUAN = 1;
		DUAN = 0;
		P0 = 0xfd;
		WEI  = 1;
		WEI  = 0;
		delay(200);

		P0 = sz[1];		// 數字1
		DUAN = 1;
		DUAN = 0;
		P0 = 0xfe;
		WEI  = 1;
		WEI  = 0;
		delay(200);

	
	
	}
}

不用延遲函式

#include<reg52.h>
sbit DUAN = P2^6;
sbit WEI  = P2^7;



unsigned code sz[17] = { 0x3f,0x06,0x5b,0x4f,0x66,0x6d,
  						 0x7d,0x07,0x7f,0x6f,0x77,0x7c,
						 0x39,0x5e,0x79,0x71,0x00
};
void main()
{
	while(1)
	{
		P0 = sz[1];		// 數字1
		DUAN = 1;		// 一端上電
		DUAN = 0;		//	 斷開
		P0 = 0xfe;
		WEI  = 1;		//	另一端上高電平
		WEI  = 0;		//	另一端斷開
		P0 = 0xff;		// 不用延遲函式需要開一個關一個才能保證不亂碼
		WEI  = 1;
		WEI  = 0;
		

		P0 = sz[2];		// 數字2
		DUAN = 1;
		DUAN = 0;
		P0 = 0xfd;
		WEI  = 1;
		WEI  = 0;
		P0 = 0xff;
		WEI  = 1;
		WEI  = 0;

		

		P0 = sz[3];		// 數字3
		DUAN = 1;
		DUAN = 0;
		P0 = 0xfb;
		WEI  = 1;
		WEI  = 0;
		P0 = 0xff;
		WEI  = 1;
		WEI  = 0;

		P0 = sz[4];		// 數字4   
		DUAN = 1;
		DUAN = 0;
		P0 = 0xf7;
		WEI  = 1;
		WEI  = 0;
		P0 = 0xff;
		WEI  = 1;
		WEI  = 0;

		P0 = sz[5];		// 數字5
		DUAN = 1;
		DUAN = 0;
		P0 = 0xef;
		WEI  = 1;
		WEI  = 0;
		P0 = 0xff;
		WEI  = 1;
		WEI  = 0;

		P0 = sz[6];		// 數字6	 
		DUAN = 1;
		DUAN = 0;
		P0 = 0xdf;
		WEI  = 1;
		WEI  = 0;
		P0 = 0xff;
		WEI  = 1;
		WEI  = 0;

		P0 = sz[7];		// 數字7
		DUAN = 1;
		DUAN = 0;
		P0 = 0xbf;
		WEI  = 1;
		WEI  = 0;
		P0 = 0xff;
		WEI  = 1;
		WEI  = 0;

		P0 = sz[8];		// 數字8
		DUAN = 1;
		DUAN = 0;
		P0 = 0x7f;
		WEI  = 1;
		WEI  = 0;
		P0 = 0xff;
		WEI  = 1;
		WEI  = 0;
	}
}