#include <reg52.h>
#include <stdio.h>

void timer0int(void);
char *Puts(char* str);

float read_temp1(void);
float read_temp1_filter(void);


char cputick;
char buffer[24];
char pulseE;

char timer3;
char temp;
char vout;
int x1,x2,x3,x4,x5;

sbit RS=P1^6;
sbit E =P1^4;
sbit RW=P1^5;

sbit CLK=P1^2;
sbit Data=P1^1;
sbit CS=P1^3;

sbit CHG=P3^0;

int readADC(char n)
{
	int k;
	char i,channel;
	k=0;

	CS=0;

	if(n==0) channel= 0x0d;
	else channel=0x0f;

	for (i=0;i<4;i++)
	{
		CLK = 0;

		if(channel&8) Data =1;
		else Data = 0;
		CLK =1;
		channel <<=1;
	}

	Data = 1;
	CLK =0;

	for(i=0; i<12;i++)
	{
		k<<=1;
		CLK =1;
		CLK=0;
		if(Data) k|=1;
		else k &=~1;
	}
		CS =1;

		return k&=0xfff;
}


void timer0int(void) interrupt 1 using 1

{
 TH0 |=0xdc;
 cputick++;
}


pause(int j)
{ int i;
  for (i=0;i<j;i++)
  continue;
}


pulesE()
{
  E =1;
    ;
  E =0;
 }


void delay(int m)
{
	int j;
	for(j=0;j<=m;j++)
	continue;
}

LCDWI (char n)
{   
  RW =0;
  RS=0;
  E =0;
  P0=n;
  E =1;
  E =0;
  pause(50);
}


LCDWD(char n)
{
  RW=0;
  RS=1;
  E=0;
  P0=n;
  E=1;
  E=0;
  pause(50);
}

print_LCD(char a,char *s)
{
LCDWI(a);
while(*s != 0)
LCDWD(*s++);
}


i_LCD()
{
  RS=0;
  E=0;
  P0=0x30;pulesE();delay(10);pulesE();delay(1);pulesE();delay(1);
  P0=0x20;pulesE();pulesE();pulesE();
  LCDWI(0x38);
  LCDWI(0x0c);
  LCDWI(0x06);
  LCDWI(1);
  delay(50);
}

print_ADC()
{
 char buffer[20];
 if(++timer3<50)
 {
  timer3=0;
  sprintf(buffer,"%0.1fC   %0.1fF",read_temp1_filter(),read_temp1_filter()*9/5+32);
  print_LCD(0xc0,buffer);
  }
}

int low_pass_filter1(void)
{
	x5=x4;
	x4=x3;
	x3=x2;
	x2=x1;
	x1=readADC(0);
	return(x1+x2+x3+x4+x5)/5;
}

float read_temp1_filter(void)
{
	return(0.0323*low_pass_filter1()-15.615);
}


void main()
{
 i_LCD();
 print_LCD(0x80,"LCD Thermometer");
 TMOD |= 0x01;
 TR0 = 1;
 cputick = 0;
 EA = 1;
 ET0 = 1;
 
  for(;;)
 {
	while(!TF0)
	continue;
	TF0=0;
	print_ADC();
 }
}