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如何將單點SHT11溫濕度傳感器測量系統改為多點的?
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單點的原理圖
2017-5-15 19:44 上傳
- /*************端口定義********************
- P1.0------SCK (SHT11)
- P1.1------DATA (SHT11)
- P0------DB0~DB7 (LCD1602)
- P2.0------RS (LCD1602)
- P2.1------RW (LCD1602)
- P2.2------E (LCD1602)
- *****************************************/
- #include <reg52.h>
- #include <intrins.h>
- #include <stdio.h>
- #include <string.h>
- #include <absacc.h>
- #include <math.h>
- #define uchar unsigned char
- #define uint unsigned int
- #define TEMPUP 25 //溫度上限
- #define TEMPDOWN 18 //溫度下限
- #define HUMDOWN 45 //濕度上限
- #define HUMUP 75 //濕度下限
- sbit LcdRs= P2^0; //1602液晶端口定義
- sbit LcdRw= P2^1;
- sbit LcdEn= P2^2;
- sbit led1 =P3^0; //報警燈端口定義
- sbit led2 =P3^4;
- sbit beep =P3^1; //定義蜂鳴器端口
- sbit ACC0 = ACC^0;
- sbit ACC7 = ACC^7;
- /******************************************************************/
- /* 延時函數聲明 */
- /******************************************************************/
- void mdelay(unsigned int t)
- {
- unsigned char n;
- for(;t>0;t--)
- for(n=0;n<125;n++)
- {;}
- }
- bit start;
- uchar str[7];
- //向LCD寫入命令或數據************************************************************
- #define LCD_COMMAND 0 // Command
- #define LCD_DATA 1 // Data
- #define LCD_CLEAR_SCREEN 0x01 // 清屏
- #define LCD_HOMING 0x02 // 光標返回原點
- //設置顯示模式************************************************************
- #define LCD_SHOW 0x04 //顯示開
- #define LCD_HIDE 0x00 //顯示關
- #define LCD_CURSOR 0x02 //顯示光標
- #define LCD_NO_CURSOR 0x00 //無光標
- #define LCD_FLASH 0x01 //光標閃動
- #define LCD_NO_FLASH 0x00 //光標不閃動
- //設置輸入模式************************************************************
- #define LCD_AC_UP 0x02
- #define LCD_AC_DOWN 0x00 // default
- #define LCD_MOVE 0x01 // 畫面可平移
- #define LCD_NO_MOVE 0x00 //default
- unsigned char LCD_Wait(void);
- void LCD_Write(bit style, unsigned char input);
- /***********1602液晶顯示部分子程序****************/
- void delay(uint z) //延時函數
- {
- uint x,y;
- for(x=z;x>0;x--)
- for(y=110;y>0;y--);
- }
- void LCD_Write(bit style, unsigned char input)
- {
- LcdRs=style;
- P0=input;
- delay(5);
- LcdEn=1;
- delay(5);
- LcdEn=0;
- }
- void LCD_SetDisplay(unsigned char DisplayMode) //設置輸出
- {
- LCD_Write(LCD_COMMAND, 0x08|DisplayMode);
- }
- void LCD_SetInput(unsigned char InputMode) //設置輸入
- {
- LCD_Write(LCD_COMMAND, 0x04|InputMode);
- }
- void LCD_Initial() //初始化LCD函數
- {
- LcdEn=0;
- LCD_Write(LCD_COMMAND,0x38); //8位數據端口,2行顯示,5*7點陣
- LCD_Write(LCD_COMMAND,0x38);
- LCD_SetDisplay(LCD_SHOW|LCD_NO_CURSOR); //開啟顯示, 無光標
- LCD_Write(LCD_COMMAND,LCD_CLEAR_SCREEN); //清屏
- LCD_SetInput(LCD_AC_UP|LCD_NO_MOVE); //AC遞增, 畫面不動
- }
- void GotoXY(unsigned char x, unsigned char y) //液晶字符輸入的位置
- {
- if(y==0)
- LCD_Write(LCD_COMMAND,0x80|x);
- if(y==1)
- LCD_Write(LCD_COMMAND,0x80|(x-0x40));
- }
- void Print(unsigned char *str) //將字符輸出到液晶顯示
- {
- while(*str!='\0')
- {
- LCD_Write(LCD_DATA,*str);
- str++;
- }
- }
- void zhuanhuan(float a)//浮點數轉換成字符串函數
- {
- memset(str,0,sizeof(str));
- sprintf (str,"%f", a);
- }
- void welcome() //初始界面函數
- {
- LCD_Initial();
- GotoXY(0,0);
- Print(" Welcome! ");
- GotoXY(0,1);
- Print(" Code of sht11 ");
- delay(200);
- }
- void delay_n10us(uint n) //延時n個10us@12M晶振
- {
- uint i;
- for(i=n;i>0;i--)
- {
- _nop_();_nop_();_nop_();
- _nop_();_nop_();_nop_();
- }
- }
- /*********************第一部分LCD1602設置 END****************************************/
- /*********************第二部分SHT11設置 START**************************************/
- sbit SCK = P1^0; //定義通訊時鐘端口
- sbit DATA = P1^1; //定義通訊數據端口
- typedef union
- { unsigned int i; //定義了兩個共用體
- float f;
- } value;
- enum {TEMP,HUMI}; //TEMP=0,HUMI=1
- #define noACK 0 //用于判斷是否結束通訊
- #define ACK 1 //結束數據傳輸
- //adr command r/w
- #define STATUS_REG_W 0x06 //000 0011 0
- #define STATUS_REG_R 0x07 //000 0011 1
- #define MEASURE_TEMP 0x03 //000 0001 1
- #define MEASURE_HUMI 0x05 //000 0010 1
- #define RESET 0x1e //000 1111 0
- /****************定義函數****************/
- void s_transstart(void); //啟動傳輸函數
- void s_connectionreset(void); //連接復位函數
- char s_write_byte(unsigned char value);//SHT11寫函數
- char s_read_byte(unsigned char ack); //SHT11讀函數
- char s_measure(unsigned char *p_value, unsigned char *p_checksum, unsigned char mode);//測量溫濕度函數
- void calc_dht90(float *p_humidity ,float *p_temperature);//溫濕度補償
- void s_transstart(void) //啟動傳輸函數
- // generates a transmission start
- // _____ ________
- // DATA: |_______|
- // ___ ___
- // SCK : ___| |___| |______
- {
- DATA=1; SCK=0; //Initial state
- _nop_();
- SCK=1;
- _nop_();
- DATA=0;
- _nop_();
- SCK=0;
- _nop_();_nop_();_nop_();
- SCK=1;
- _nop_();
- DATA=1;
- _nop_();
- SCK=0;
- }
- void s_connectionreset(void) //連接復位函數
- // communication reset: DATA-line=1 and at least 9 SCK cycles followed by transstart
- // _____________________________________________________ ________
- // DATA: |_______|
- // _ _ _ _ _ _ _ _ _ ___ ___
- // SCK : __| |__| |__| |__| |__| |__| |__| |__| |__| |______| |___| |______
- {
- unsigned char i;
- DATA=1; SCK=0; //Initial state
- for(i=0;i<9;i++) //9 SCK cycles
- {
- SCK=1;
- SCK=0;
- }
- s_transstart(); //transmission start
- }
- char s_write_byte(unsigned char value) // SHT11寫字節函數
- //----------------------------------------------------------------------------------
- // writes a byte on the Sensibus and checks the acknowledge
- {
- unsigned char i,error=0;
- for (i=0x80;i>0;i/=2) //shift bit for masking
- {
- if (i & value) DATA=1; //masking value with i , write to SENSI-BUS
- else DATA=0;
- SCK=1; //clk for SENSI-BUS
- _nop_();_nop_();_nop_(); //pulswith approx. 3 us
- SCK=0;
- }
- DATA=1; //release DATA-line
- SCK=1; //clk #9 for ack
- error=DATA; //check ack (DATA will be pulled down by DHT90),DATA在第9個上升沿將被DHT90自動下拉為低電平。
- _nop_();_nop_();_nop_();
- SCK=0;
- DATA=1; //release DATA-line
- return error; //error=1 in case of no acknowledge //返回:0成功,1失敗
- }
- /*****SHT11讀函數 reads a byte form the Sensibus
- and gives an acknowledge in case of "ack=1"****/
- char s_read_byte(unsigned char ack)
- {
- unsigned char i,val=0;
- DATA=1; //release DATA-line
- for (i=0x80;i>0;i/=2) //shift bit for masking
- { SCK=1; //clk for SENSI-BUS
- if (DATA) val=(val | i); //read bit
- _nop_();_nop_();_nop_(); //pulswith approx. 3 us
- SCK=0;
- }
- if(ack==1)DATA=0; //in case of "ack==1" pull down DATA-Line
- else DATA=1; //如果是校驗(ack==0),讀取完后結束通訊
- _nop_();_nop_();_nop_(); //pulswith approx. 3 us
- SCK=1; //clk #9 for ack
- _nop_();_nop_();_nop_(); //pulswith approx. 3 us
- SCK=0;
- _nop_();_nop_();_nop_(); //pulswith approx. 3 us
- DATA=1; //release DATA-line
- return val;
- }
- /* 測量溫濕度函數 makes a measurement
- (humidity/temperature) with checksum */
- char s_measure(unsigned char *p_value, unsigned char *p_checksum, unsigned char mode)
- {
- unsigned error=0;
- unsigned int i;
- s_transstart(); //transmission start
- switch(mode){ //send command to sensor
- case TEMP : error+=s_write_byte(MEASURE_TEMP); break;
- case HUMI : error+=s_write_byte(MEASURE_HUMI); break;
- default : break;
- }
- for (i=0;i<65535;i++) if(DATA==0) break; //wait until sensor has finished the measurement
- if(DATA) error+=1; // or timeout (~2 sec.) is reached
- *(p_value) =s_read_byte(ACK); //read the first byte (MSB)
- *(p_value+1)=s_read_byte(ACK); //read the second byte (LSB)
- *p_checksum =s_read_byte(noACK); //read checksum
- return error;
- }
- void calc_sht90(float *p_humidity ,float *p_temperature) //溫濕度補償函數
- // calculates temperature [C] and humidity [%RH]
- // input : humi [Ticks] (12 bit)
- // temp [Ticks] (14 bit)
- // output: humi [%RH]
- // temp [C]
- { const float C1=-4.0; // for 12 Bit
- const float C2=+0.0405; // for 12 Bit
- const float C3=-0.0000028; // for 12 Bit
- const float T1=+0.01; // for 14 Bit @ 5V
- const float T2=+0.00008; // for 14 Bit @ 5V
- float rh=*p_humidity; // rh: Humidity [Ticks] 12 Bit
- float t=*p_temperature; // t: Temperature [Ticks] 14 Bit
- float rh_lin; // rh_lin: Humidity linear
- float rh_true; // rh_true: Temperature compensated humidity
- float t_C; // t_C : Temperature [C]
- t_C=t*0.01 - 40; //calc. temperature from ticks to [C]
- rh_lin=C3*rh*rh + C2*rh + C1; //calc. humidity from ticks to [%RH]
- rh_true=(t_C-25)*(T1+T2*rh)+rh_lin; //calc. temperature compensated humidity [%RH]
- if(rh_true>100)rh_true=100; //cut if the value is outside of
- if(rh_true<0.1)rh_true=0.1; //the physical possible range
- *p_temperature=t_C; //return temperature [C]
- *p_humidity=rh_true; //return humidity[%RH]
- }
- /**************第二部分SHT11設置 END*****************************/
- /***************************主函數************************************/
- void main(void)
- {
- int a,b;
- value humi_val,temp_val;
- unsigned char error,checksum,i;
- LcdRw=0;
- led1=0;
- led2=0;
- beep=1;
- start=0;
- s_connectionreset();
- welcome();//顯示歡迎畫面
- delay(2000);
- LCD_Initial();
- while(1)
- { error=0;
- error+=s_measure((unsigned char*) &humi_val.i,&checksum,HUMI);
- error+=s_measure((unsigned char*) &temp_val.i,&checksum,TEMP);
- if(error!=0)
- s_connectionreset(); //in case of an error: connection reset
- else
- {
- humi_val.f=(float)humi_val.i; //converts integer to float
- temp_val.f=(float)temp_val.i; //converts integer to float
- calc_sht90(&humi_val.f,&temp_val.f); //計算濕度與溫度
- GotoXY(0,0);//
- Print("Tep:");
- GotoXY(0,1);
- Print("Hum:");
- zhuanhuan(temp_val.f); //轉換溫度為uchar方便液晶顯示
- GotoXY(5,0);
- str[5]=0xDF;//℃的符號
- str[6]=0x43;
- str[7]='\0';
- Print(str);
- if( temp_val.f>TEMPUP-1 || temp_val.f<TEMPDOWN-1 )
- {
- //led1=1;
- // beep=1;
- a=1;
- }
- else
- {
- //led1=0;
- // beep=0;
- a=0 ;
- }
- zhuanhuan(humi_val.f);//轉換濕度為uchar方便液晶顯示
- GotoXY(5,1);
- str[5]='%';//%的符號
- str[6]='\0';//字符串結束標志
- Print(str);
- if( humi_val.f>HUMUP-1 || humi_val.f<HUMDOWN-1 )
- // { led2=1;
- // beep2=1;}
- {
- //led2=1;
- // beep=1;
- b=1;
- }
- else
- {
- //led2=0;
- // beep=0;
- b=0;
- }
- if(a==1&&b==1)
- {
- led1=1;
- led2=1;
- beep=0;
- }
- else if(a==1&&b==0)
- {
- led1=1;
- led2=0;
- beep=0;
- }
- else if(a==0&&b==1)
- {
- led1=0;
- led2=1;
- beep=0;
- }
- else if(a==0&&b==0)
- {
- led1=0;
- led2=0;
- beep=1;
- }
- // if(a==1||b==1)
- // beep=1;
- // else
- // beep=0;
- // a=b=0;
- }
- delay_n10us(80000); //延時約0.8s
- }
- }
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