原创 AD7705应用又C51源程序

 2007-10-25 09:55  4679 6 7 分类: 汽车电子

#include<reg52.h>
#include<absacc.h>
#include<intrins.h>
#include<math.h>

sbit Number_BIT0 = P2^7;
sbit Number_BIT1 = P2^6;
sbit Number_BIT2 = P2^5;
sbit Number_BIT3 = P2^4;
sbit BUZZER = P2^3;

sbit AD7705_DATA=P3^0; // AD7705 input & output data
sbit AD7705_CLK=P3^1; // AD7705 CLK

sbit AD7705_DRDY=P1^2; // AD7705 data ready
sbit AD7705_CS =P1^3; // AD7705 CS

unsigned char Counter,dis_index,dis_digit;
float T_Voltage;
unsigned char MSB_Data,LSB_Data,temp0,temp1,temp2,temp3,temp4,temp5;

unsigned char code Display_code[11]=
//{0xa0,0xF9,0xc4,0xd0,0x99,0x92,0x82,0xF8,0x80,0x90,0xFF,};
{0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90,0xFF};

void Delayms(unsigned char ms);
void AD7705_Start();
void AD7705_Read ();
void AD7705_Write_Reg(unsigned char Data_byte);
unsigned char AD7705_Read_Reg();

main()
{
TMOD = 0x11;
IT0 = 1;
PCON=0X00;
ET0 = 1;
TH1 = 0xFC;
TL1 = 0x17;
    TR0 = 1;

EA = 1;
P0 = 0xff; P1 = 0xff; P2 = 0xf7; P3 = 0xff;
dis_digit = 0x77;
dis_index = 0;
Counter = 0;
AD7705_Start();

while(1)
{
while(AD7705_DRDY);
    AD7705_Read();
Delayms(50);
}
}

void Delayms(unsigned char ms)
// relay ms
{ unsigned char i;
while(ms--)
{
for(i = 0; i < 120; i++);
}
}

void AD7705_Start()
{
AD7705_Write_Reg(0x20);
AD7705_Write_Reg(0x0c);
AD7705_Write_Reg(0x10);
AD7705_Write_Reg(0x44);
}
/*****************************************/
void AD7705_Read()
{
AD7705_Write_Reg(0x38);
MSB_Data = AD7705_Read_Reg();
LSB_Data = AD7705_Read_Reg();
T_Voltage =(float)MSB_Data;
T_Voltage = T_Voltage*100;
T_Voltage = T_Voltage + (float)LSB_Data;

temp0 = T_Voltage/100000;
temp1 = ((T_Voltage-temp0*100000)/10000);
temp2 = ((T_Voltage-temp0*100000-temp1*10000)/1000);
temp3 = ((T_Voltage-temp0*100000-temp1*10000-temp2*1000)/100);
temp4 = (T_Voltage-temp0*100000-temp1*10000-temp2*1000-temp3*100)/10;
temp5 = (T_Voltage-temp0*100000-temp1*10000-temp2*1000-temp3*100-temp4*10);

}
/*******************************************/

void AD7705_Write_Reg(unsigned char Data_byte)
{
unsigned char i;
AD7705_CS = 0;
AD7705_CLK = 1;
        _nop_();
  _nop_();
for(i = 0; i < 8; i++)
{
     AD7705_DATA = (bit)(Data_byte & 0x80);
  AD7705_CLK = 0;
        _nop_();
  _nop_();
  _nop_();
  AD7705_CLK = 1;

     Data_byte <<= 1;
}
  _nop_();
  AD7705_CS = 1;
}
unsigned char AD7705_Read_Reg()
{
unsigned char i,Data_read;
AD7705_CS = 0;
AD7705_CLK = 1;
     _nop_();
for(i = 0; i < 8; i++)
{
     AD7705_CLK = 0;
        _nop_();
     _nop_();
  Data_read <<= 1;
  Data_read |= (unsigned char)AD7705_DATA;
  _nop_();
  _nop_();
        AD7705_CLK = 1;
        _nop_();
     _nop_();
}
_nop_();
  AD7705_CS = 1;
  AD7705_DRDY = 1;
  return(Data_read);
}

void time0(void) interrupt 1
{
TR0 = 0;
P2 = dis_digit;   //P2.7 --DS8
P0 = Display_code[dis_index];

TH0 = 0xFC;
TL0 = 0x17;
Counter++;
if(Counter==1)
{
dis_digit = 0x77;
  dis_index = temp5;
    }else if(Counter==2)
{
dis_digit = 0xb7;
  dis_index = temp4;
}else if(Counter==3)
{
dis_digit = 0xd7;
  dis_index = temp3;
}else if(Counter==4)
{
dis_digit = 0xe7;
  dis_index = temp2;
Counter = 0;
}

    TR0 = 1;
}