本帖最后由 151huh 于 2019-12-26 11:41 編輯
使用的元件有stc89c52，npn三極管，四位一體共陰數(shù)碼管，DHT11.
仿真
代碼文件 - #include <reg52.h>
- #define duanxuan P0
- #define weixuan P2
- sbit Data = P1^0;[/align][align=left]
- void delay_us(int num)//us延時函數(shù)
- {
- int cnt = 0;
- TMOD = 0x01;
- TH0 = 0xFF; //設置延時1us
- TL0 = 0xFF;
- TR0 = 1;
- while(1)
- {
- if(TF0 == 1)
- {
- TF0 = 0;
- TH0 = 0xFF;
- TL0 = 0XFF;
- cnt++;
- if(cnt >= num)
- break;
- }
- }
-
- }void delay_ms(int shuzhi)//ms延時函數(shù)
- {
- int cnt = 0;
- TMOD = 0x01;
- TH0 = 0x03; //設置延時1ms
- TL0 = 0xE8;
- TR0 = 1;
- while(1)
- {
- if(TF0 == 1)
- {
- TF0 = 0;
- TH0 = 0x03;
- TL0 = 0XE8;
- cnt++;
- if(cnt >= shuzhi)
- break;
- }
- }
- }
- void Xianshi(int a, d)//數(shù)碼管顯示函數(shù)
- {
- unsigned char code wxcode[4] = {0xfe,0xfd,0xfb,0xf7};//位選編碼表
- unsigned char code dxcode[10] = {0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f}; //段選編碼表
- unsigned char i;
- unsigned int g, s, b, q, j;
-
- g = a%10;//個位
- s = a/10%10; //十位
- b = b%10; //百位
- q = b/10%10; //千位
-
- for(i=0;i<4;i++)
- {
- weixuan = wxcode[i];
- duanxuan = 0x00;
- if(i==3)
- duanxuan = dxcode[g];
- if(i==2)
- duanxuan = dxcode[s];
- if(i==1)
- duanxuan = dxcode[b];
- if(i==0)
- duanxuan = dxcode[q];
- }
- j = 100;
- while(j--);
- }
- [align=left]void DHT_star()//溫濕度讀取函數(shù)
- {
- Data = 1;
- delay_us(20);
- Data = 0;
- delay_ms(20); //主機發(fā)送起始信號
- Data = 1;
- delay_us(30);
- }
- unsigned char DHT_code() //DHT11接受一個字節(jié)
- {
- unsigned char i;
- unsigned char dat = 0;
- for(i=0;i<8;i++)
- {
- while(!Data); //等待50us的低電平過去
- delay_us(60); //延時60us如果還為高電平則數(shù)據(jù)為1
- dat <<= 1; //數(shù)據(jù)為0時直接執(zhí)行移位操作
- if(Data==1) //數(shù)據(jù)為1時，加1
- dat += 1;
- while(Data); //等待數(shù)據(jù)線拉低
- }
- return dat;
- }[/align][align=left]void DHT_receive()
- {
- unsigned char R_H, R_L, T_H, T_L, RH=0, RL, TH=0, TL, revise;
- DHT_star();
- if(Data==0)
- {
- while(Data == 0); //等待數(shù)據(jù)線拉高
- delay_us(80);
- R_H = DHT_code(); //接受8位濕度整數(shù)數(shù)據(jù)
- R_L = DHT_code(); //接受8位濕度小數(shù)數(shù)據(jù)
- T_H = DHT_code(); //接受8位溫度整數(shù)數(shù)據(jù)
- T_L = DHT_code(); //接受8位溫度小數(shù)數(shù)據(jù)
- revise = DHT_code(); //接受檢驗數(shù)據(jù)[/align][align=left] delay_us(30);[/align][align=left] if((R_H+R_L+T_H+T_L)==revise) //校驗數(shù)據(jù)是否正確
- {
- RH = R_H;
- RL = R_L;
- TH = T_H;
- TL = T_L;
- }
- }
- Xianshi(RH, TH); //顯示濕度整數(shù)，溫度整數(shù)
- }[/align][align=left]void main()//主函數(shù)
- {
- while(1)
- {
- delay_ms(1500); //DHT11上電后等待超過1s以越過不穩(wěn)定狀態(tài)
- DHT_receive();
- }
- }
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