manigr8
Newbie level 2
Hi, I'm facing problem interfacing ADC and 89c51. I'm giving an analog voltage to ADC 0804 from 0-5 volts and the output is connected to port 1 of 89c51. the port 2 of microcontroller is connected to 8 bit LCD. I want to callibrate, when i change the voltage from 0-5 the LCD displays from 0-100. Vref/2 is open, step size is 19.53mV. I've trid a lot but there is nothing on the Lcd except a cursor that shifts towads right three time. I would be very thankful if someone help me trace out the fault.
#include <reg51.h>
#define output P2
#define cmdport P3
#define input P1
sbit read = P3^5;
sbit write =P2^2;
sbit INTR =P2^7;
sbit rs= cmdport^0; //lcd instruction
sbit rw=cmdport^1;
sbit e = cmdport^6;
void delay(unsigned int);
void lcdcmd(unsigned int);
void lcd();
void lcddata(unsigned int);
void main ()
{
unsigned char temp,x,a,b,c,y;
INTR=1;
read=1;
write=1;
while (1)
{
lcd();
write=0;
write=1;
while(INTR==1);
read=1;
y=input;
temp=y/2.55;
x=temp/10;
a=temp%10;
b=x%10;
c=x/10;
lcddata(c);
lcddata(b);
lcddata(a);
read=0;
}
}
void lcd()
{
delay(10);
lcdcmd(0x38); //lcd command
delay(10);
lcdcmd(0x0E); //lcd command
delay(10);
lcdcmd(0x01);
delay(10);
lcdcmd(0x06);
delay(10);
}
// DELAY
void delay(unsigned int msec )
{
unsigned int i;
for (i=0; i<msec; i++)
{
TMOD=0x01;
TH0=0x00;
TL0=0x0f;
TR0=1;
while(TF0==0);
TR0=0;
TF0=0;
}
}
// LCD instructions
void lcdcmd(unsigned int item)
{
P2 = item;
rs=0;
rw=0;
e=1;
delay(1);
e=0;
}
// Display Value
void lcddata(unsigned char j)
{
rs=1;
rw=0;
P2 =j;
e=1;
delay(1);
e=0;
}
#include <reg51.h>
#define output P2
#define cmdport P3
#define input P1
sbit read = P3^5;
sbit write =P2^2;
sbit INTR =P2^7;
sbit rs= cmdport^0; //lcd instruction
sbit rw=cmdport^1;
sbit e = cmdport^6;
void delay(unsigned int);
void lcdcmd(unsigned int);
void lcd();
void lcddata(unsigned int);
void main ()
{
unsigned char temp,x,a,b,c,y;
INTR=1;
read=1;
write=1;
while (1)
{
lcd();
write=0;
write=1;
while(INTR==1);
read=1;
y=input;
temp=y/2.55;
x=temp/10;
a=temp%10;
b=x%10;
c=x/10;
lcddata(c);
lcddata(b);
lcddata(a);
read=0;
}
}
void lcd()
{
delay(10);
lcdcmd(0x38); //lcd command
delay(10);
lcdcmd(0x0E); //lcd command
delay(10);
lcdcmd(0x01);
delay(10);
lcdcmd(0x06);
delay(10);
}
// DELAY
void delay(unsigned int msec )
{
unsigned int i;
for (i=0; i<msec; i++)
{
TMOD=0x01;
TH0=0x00;
TL0=0x0f;
TR0=1;
while(TF0==0);
TR0=0;
TF0=0;
}
}
// LCD instructions
void lcdcmd(unsigned int item)
{
P2 = item;
rs=0;
rw=0;
e=1;
delay(1);
e=0;
}
// Display Value
void lcddata(unsigned char j)
{
rs=1;
rw=0;
P2 =j;
e=1;
delay(1);
e=0;
}
