数字温湿度变送器自动标定仪设计论(6)

BYTE readdata_555() //555握手

{ P3M1 = 0XFF; P3M0 = 0XFF; date = 0; delaytime(300); //延时*us

date = 1;

delaytime(2); // *us P3M1 = 0XFF; P3M0 = 0X00; TH0 = 0; TL0 = 0;

while(date); // 等待拉低 TR0 = 1;

_nop_ ();

_nop_ ();

_nop_ ();

_nop_ (); while(!date); // 约31us TR0 = 0;

if(TL0<34&&TL0>28) return 1;

else

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return 0;

}

//--------------------------------------------------------------- void conmu_555() { BYTE che; BYTE jiao,check; BYTE th,tl; WORD temp; che = readdata_555(); if(che) { while(date); th = read_byte(); tl = read_byte(); hum = read_byte(); jiao = read_byte(); temp = th<<8;

tem = temp|tl;

} check = th^tl; check = check^hum; if(jiao != check)

hum = 5;

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P3M1 = 0X00; P3M0 = 0X00;

}

//-------------------------------------------------------------- void lcd_555()

//显示字

{ char i; LCD_send_command(0x80); for(i=0;i<4;i++) { LCD_send_data(t[i]); delay(15);

}

LCD_send_command(0x80+10); for(i=0;i<4;i++)

{ LCD_send_data(rt[i]);

delay(15);

} }

//---------------------------------------------- void UartInit(void)

//9600bps@12MHz

{ PCON &= 0x7f; //波特率不倍速 SCON = 0x50;

//8位数据,可变波特率

BRT = 0xD9;

//设定独立波特率发生器重装值- 28 -

AUXR |= 0x04; //独立波特率发生器时钟为Fosc,即1T

AUXR |= 0x01;//串口1选择独立波特率发生器为波特率发生器 AUXR |= 0x10;

//启动独立波特率发生器

}

void UART_T(unsigned char UART_data) { //定义串口发送数据变量 // ES=0; //禁止穿行中断 SBUF = UART_data; //将接收的数据发送回去 while(TI == 0); //检查发送中断标志位

TI = 0; //令发送中断标志位为0（软件清零）

// ES=1; //打开穿行中断 // delay(100); }

//-------------频率----------------------------- sbit checkFre = P3^3; //检测频率脚 double

Frequency;

//Hz

double F55;

double gain = (3.35272e-3);

WORD calculateFrequency() //计时25个周期 { BYTE t_num = 25; TH0 = 0;

TL0 = 1;

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EA = 0;

while(checkFre==0); _nop_ ();_nop_ (); while(1)

{ if(checkFre==0) break;

} TR0=1;

//等待负跳变开始计时 while(t_num--) { while(1)

{ if(checkFre==1) break;

} while(1)

{ if(checkFre==0) break;

} }

TR0=0; //下次负跳变停止计时 EA = 1;

return((300000.0/(TH0*256+TL0))*1000);

}

void calFre()

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