c51單片機03數(shù)碼管

1、第3講 LED數(shù)碼管顯示,,HOT-51增強型開發(fā)板數(shù)碼管接口,,共陰極數(shù)碼管,僅當段位接高電平，陰極接低電平時，相應位的LED才導通發(fā)光,a b c d e f g bp,共陽極數(shù)碼管,僅當段位接低電平，陽極接高電平時，相應位的LED才導通發(fā)光,,a b c d e f g bp,Vcc,七段數(shù)碼管的段位控制,,,,,

2、,,,,a,g,d,b,c,e,f,,dp,dp g f e d c b a 0 0 1 1 1 1 1 1,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,b,c,e,f,,dp,dp g f e d c b a 0 0 0 0 0 1 1 0,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,b,c,e,f,,dp,dp g f e d c b a

3、 0 1 0 1 1 0 1 1,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,b,c,e,f,,dp,dp g f e d c b a 0 0 1 1 1 1 1 1,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,b,c,e,f,,dp,dp g f e d c b a 0 1 1 0 0 1 1 0,七段數(shù)碼管的段位控制,,,,,,,,,a

4、,g,d,b,c,e,f,,dp,dp g f e d c b a 0 1 1 0 1 1 0 1,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,b,c,e,f,,dp,dp g f e d c b a 0 1 1 1 1 1 0 1,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,b,c,e,f,,dp,dp g f e d c b a 0

5、 0 0 0 0 1 1 1,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,b,c,e,f,,dp,dp g f e d c b a 0 1 1 1 1 1 1 1,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,b,c,e,f,,dp,dp g f e d c b a 0 1 1 0 0 1 1 1,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,

6、b,c,e,f,,dp,dp g f e d c b a 0 1 1 1 0 1 1 1,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,b,c,e,f,,dp,dp g f e d c b a 0 1 1 1 1 1 0 0,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,b,c,e,f,,dp,dp g f e d c b a 0 0 1

7、 1 1 0 0 1,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,b,c,e,f,,dp,dp g f e d c b a 0 1 0 1 1 1 1 0,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,b,c,e,f,,dp,dp g f e d c b a 0 1 1 1 1 0 0 1,七段數(shù)碼管的段位控制,,,,,,,,,a,g,d,b,c,e

8、,f,,dp,dp g f e d c b a 0 1 1 1 0 0 0 1,,七段數(shù)碼管與段位控制代碼,,鎖存器,,上升沿寫入,,段位控制碼,鎖存器,,下降沿鎖存,段位控制碼,,3－8線譯碼器選擇數(shù)碼管,,,選擇數(shù)碼管,,接數(shù)碼管陰極,74HC138是3－8線譯碼器，任何時候Y7~Y0只能有一個輸出為“0”,數(shù)碼管的靜態(tài)顯示,#includevoid Main(void){P2=0;

9、//選擇最左邊的數(shù)碼管P0=0x6d;//顯示數(shù)字“5”},P2端口只有低三位可以用來選擇數(shù)碼管,練習與思考,練習：在最右邊的數(shù)碼管上顯示數(shù)字“9”思考：在本電路中，按照靜態(tài)顯示方法，有沒有可能讓兩個數(shù)碼管同時顯示相同的數(shù)字？,74HC138是3－8線譯碼器，任何時候Y7~Y0只能有一個輸出為“0”,,練習,在8個LED數(shù)碼管上，按從左到右的順序，循環(huán)滾動顯示數(shù)字“5”，每次滾動延時500ms,數(shù)碼管的滾動顯示,#in

10、cludeunsigned char LED;void Delay(unsigned int milisec)//延時1ms{unsigned int i,j;for(i=milisec;i>0;i--)//雙重for循環(huán)實現(xiàn)延時1msfor(j=110;j>0;j--);}void Main(void){P0=0x6d;//顯示數(shù)字“5”while(1){for(

11、LED=0; LED<=7; LED++){P2=LED;//選擇LED，實現(xiàn)滾動顯示Delay(500);//延時500ms}}},觀察,對于上一個練習，逐步減少每次滾動的延時，直到減為2ms，觀察到什么現(xiàn)象？,數(shù)碼管的動態(tài)顯示,任務：在8個LED上穩(wěn)定地顯示“01234567”分析：8個LED的對應段位是并聯(lián)在一起的，只能通過控制陰極電位來選擇允許哪個LED發(fā)光t1時刻允許L

12、ED0顯示“0”t2時刻允許LED1顯示“1”……8個LED輪流顯示，只要切換速度足夠快，看上去就是8個LED都在穩(wěn)定地顯示,數(shù)碼管的動態(tài)顯示（數(shù)據(jù)準備）,#includeunsigned char code table[10] = {0x3f,0x06,0x5b,0x4f,0x66, 0x6d,0x7d,0x07,0x7f,0x6f};unsigned char code LED[8] = {0,1,2,3,4,

13、5,6,7};void Delay(unsigned int milisec) //延時1ms{unsigned int i,j;for(i=milisec;i>0;i--)for(j=110;j>0;j--);},數(shù)碼管的動態(tài)顯示（主函數(shù)）,void Main(void){unsigned char i = 0;while(1){P0 = table[i]; // 取一個

14、數(shù)的段位碼P2 = LED[i]; //點亮一個數(shù)碼管Delay(2);//延時2msi++;//移位if(i == 8)i = 0;//重新開始}},定義數(shù)組,unsigned char code table[10] = {0x3f,0x06,0x5b,0x4f,0x66, 0x6d,0x7d,0x07,0x7f,0x6f};使用code，程序編譯后，則將數(shù)組tab

15、le[]保存到程序存儲器(FLASH)，否則就會保存到數(shù)據(jù)存儲器（RAM）RAM是單片機的“緊缺資源”，能省則省,練習,在8個LED當中，選擇靠右邊的4個LED顯示數(shù)字“3210”,void Main(void){unsigned char i = 7;while(1){P0 = table[7-i]; P2 = LED[i];Delay(2);i--;if(i == 3)i = 7;

16、}},練習,在8個LED上顯示計算機教研室的電話號碼“68752219”,顯示計算機教研室的電話號碼,#includeunsigned char code table[10] = {0x3f,0x06,0x5b,0x4f,0x66, 0x6d,0x7d,0x07,0x7f,0x6f};unsigned char code Number[8] = {6,8,7,5,2,2,1,9};void Delay(unsig

17、ned int milisec) //延時1ms{unsigned int i,j;for(i=milisec;i>0;i--)for(j=110;j>0;j--);},顯示計算機教研室的電話號碼,void Main(void){unsigned char i = 0,j;while(1){j = Number[i];//取一個待顯示的數(shù)P0 = table[j];

18、// 取一個數(shù)的段位碼P2 = i;//點亮一個數(shù)碼管Delay(2);//延時2msi++;//移位if(i == 8)i = 0;//重新開始}},顯示“HELLO”或“PASS”,#include//unsigned char code table[8] = //{0x00,0x00,0x00,0x76,0x79,0x38,0x38,0x3f};//HELLOuns

19、igned char code table[8]={0x00,0x00,0x00,0x00,0x73,0x77,0x6d,0x6d};//PASSvoid Delay(unsigned int milisec) //延時1ms{unsigned int i,j;for(i=milisec;i>0;i--)for(j=110;j>0;j--);}void Main(void){unsi