ADS7825 INTERFACING WITH P89V51RD2

#include <stdlib.h>
#include <p89v51rd2.h>
#include <stdio.h> 				// sprint function requires this stdio.h lib	
#include <intrins.h>		    // to use nop instruction in c
#include <math.h>
#include <string.h>	
//#include <lcd.h>
#define databus P3

sfr16 RCAP2= 0xCA;				// timer 2 address defined

sbit an0=P0^6;
sbit an1=P0^7;
//sbit ext_int= P1^0;
sbit busy=P1^1;
sbit readconvt=P1^2;
sbit sclk=P1^7;
sbit ss = P1^4;
sbit miso = P1^6;
sbit parser =P3^0;
 
//lcd bits--------
sbit rs = P0^1;
sbit rw = P0^2;
sbit en = P0^0;
//------------------------------------------
char AsciiData1[12];


void lcd_init();
void lcd_cmdwrite(unsigned int dat);
void lcd_datawrite(unsigned char dat);
void lcd_delay(int x);
void lcd_displaystring(char *string_ptr);

//-------------------------------------------

void lcd_delay(int x)
{
	int i,j;
	for(i=0;i<x;i++)
	for(j=0;j<1275;j++);
}
void lcd_cmdwrite(unsigned int dat)
{
	databus=dat;
	rs = 0;
	rw = 0;
	en = 0;
	en = 1;
	lcd_delay(1);
	en = 0;
	lcd_delay(1);
}
void lcd_datawrite(unsigned char dat)
{
	databus=dat;
	rs = 1;
	rw = 0;
	en = 0;
	en = 1;
	lcd_delay(1);
	en = 0;
	lcd_delay(1);
}
void lcd_init()
{
	P2=0x00;
lcd_cmdwrite(0x30);
lcd_cmdwrite(0x30);
lcd_cmdwrite(0x30);
lcd_cmdwrite(0x0E);
lcd_cmdwrite(0x01);
lcd_cmdwrite(0x06);		   //CLEAR DISPLAY
lcd_cmdwrite(0x80);		   //ENTRY MODE
}
//char lcd_displaystring(unsigned char *string_ptr)
//{
//	while (*string_ptr)
//		lcd_datawrite(*string_ptr++);
//}
//char display(const char *a)    //string display
//{
//	while(*a!='\0')
//	lcd_datawrite(*a++);	
//}
void Serial_Config(unsigned int baud_rate)
{
   RCAP2 = -(11059200/32/baud_rate); 
   
   SCON = 	0x50; //mode 1 receive enabled

   RCLK = 1; //Timer2 in baud rate
   TCLK = 1; //Disable Tx clock	, Enable only when required

}
void SerialOut1(char AsciiData1)
{	TR2=1;
		 SBUF = AsciiData1;
		 while(!TI);
		 TI=0;
	TR2=0;
} 
void dq1(char *AsciiData1, float dev)
{
	 sprintf( AsciiData1, "%4.8f",dev);  // string printf		
}

//--------------------------------------------
void spi_config()
{  
 SPCTL=0x53; //SPI enable bit=1; MSTR bit=1 (to configure it as master) and frequency for SPI comm. = (F)osc/8
 //SPCFG=0X00; 
 //SPDAT=0X00;    //initialize the SPI data register to 0X00
}
void send_value_flt(float vl)
{
unsigned int j,tmp;
unsigned char buff[5]={0,0,0,0,0},k=0;
float tmp_vl=0;
 
j=(int)vl;         //vl=11.256  tmp=11
 
      k=0;
       while(j!=0)
            {
                buff[k++]=(j%10);
                j/=10;
                
            }
 
             //lcd_datawrite( (buff[3]+'0') );
            // lcd_datawrite( (buff[2]+'0') );
             lcd_datawrite( (buff[1])+0x30 );
             lcd_datawrite( (buff[0])+0x30 );
 
tmp=(int)vl;        //11.25 -> 11
tmp_vl=(float)tmp;  //11 -> 11.00
vl=(vl-tmp_vl);   //11.250-11.000 => .250
j=(int)(vl*1000);   // (11.256-11.000)  = 250  
 
lcd_datawrite('.');
 
buff[0]=0;
buff[1]=0;
buff[2]=0;
buff[3]=0;
buff[4]=0;
k=0;
 while(j!=0)
        {
                buff[k++]=(j%10);
                j/=10;
        }  
 
              lcd_datawrite( (buff[2])+0x30 );
              lcd_datawrite( (buff[1])+0x30 );
              lcd_datawrite( (buff[0])+0x30 );
           
}
//-----------------------------------
float read_adc()
{
	unsigned int i;
  unsigned  char d1,n;
  unsigned  int d4;
	long float sum1=0;
float averaged_adcout1=0,adcout1=0;

//long float sum1=0;
//float adcout1=0;


//		ss=1;
//		lcd_delay(1);
//		ss=0;
//		lcd_delay(1);

readconvt = 1;
	for (n=0;n<100;n++)
	{
	sclk=0;
	lcd_delay(1);

//ext_int=1;   // make ext/int bar high to enable external data clk
                    
readconvt = 0;	
//lcd_delay(1);	//falling edge of r/c
//check busy
while (busy!=0);
//imp** make readconvt high here AFTER .04 TO 12uSEC VVIMP
readconvt = 1;
//lcd_delay(1);
while (busy==0);
//readconvt = 1;
//lcd_delay(1);
SPDAT = 0xE7;
for(i=0;i<3;i++); 
//lcd_delay(1);
//while(SPCFG!=0x80);

// if SPIF set indicating end of 8 bits of data, make it 0 and transfer data elsewhere. // make chip select go high to stop transmission of further data.
d4=0x0000;
d1=SPDAT;
d4=d1;
d4=d4<<8;	     // making d1 occupy the MS Byte
d4= d4 & 0xFF00; // making lower byte of d4 zero
SPCFG=0x00;

SPDAT= 0xCA;
//lcd_delay(1);
//while(SPCFG!=0x80);
for(i=0;i<3;i++); 
//SPCFG=0x00;
d1=SPDAT;	 
d4= d4 | d1;
d4=d4<<1;	  	 // LEFTshifting d4 to make space for last bit
SPCFG=0x00;

SPDAT= 0xF8;
////lcd_delay(1);
////while(SPCFG!=0x80);
for(i=0;i<2;i++); 
d1=SPDAT;		 
d1=d1 & 0x80;    // anding to make 0, all other bits of d1 except the MSB 
d1=d1>>7;		 // making the MSB of d1, its LSB
d1= d1&0x01;	 // to confirm only the last bit is 1;
d4= d4|d1;       // adding the last bit;
SPCFG=0x00;
//if d2 is MSB is 1, then invert all bits and add 1. and the corresponding decimal 
// will start with a negative sign.
if ((d4 & 0x8000)==0x8000)
{
	d4=~d4;
	d4=d4+1;
	adcout1=-(d4/32767.0f)*10.0f;
	//lcd_datawrite("-");
}
else {
	adcout1=(d4/32767.0f)*10.0f;
	sum1=sum1+adcout1;
}
//send_value_flt(adcout1);
}
averaged_adcout1=(sum1/100.0f);
return averaged_adcout1;
}
void main()
{
// P0=0XFF;
 //P1=0xFF;
 //P3=0XFF;
 //P2=0XFF;
	float A=0.00;
	unsigned int j;

	//char AsciiData1;
	//busy = 1;
	//miso = 1;
	lcd_init();
	
 spi_config(); 
Serial_Config(9600);  //setup the master configuration
	//parser=0;
			an0= 0;   
		an1= 0;
while(1)
    {
			lcd_cmdwrite(0x02);
			A=read_adc();
//			send_value_flt(A);
			dq1(AsciiData1, A);
//			

			//SerialOut1(AsciiData1[1]);
		//SerialOut1(AsciiData1[2]);
			for(j=0;j<9;++j)	
{	lcd_datawrite(AsciiData1[j]);
	//SerialOut1(AsciiData1[j]);
	}
SerialOut1(A);

//		lcd_datawrite(AsciiData1[4]);
//		lcd_datawrite(AsciiData1[5]);
		SerialOut1(0x0a);
		SerialOut1(0x0D);
//lcd_delay(1000);			
		}
		while(1);
}