Problem on Interfacing 8051 with 24c02

I was trying to write some values to 24c02 and read back the same value from that location.But in the serial window
I m only getting a black space in the place of data.Can any one help me regarding this problem.The code that i written was
pre>
#include <reg52.h>
#include <string.h>

#define HIGH 0x01 // Value representing ON
#define LOW 0x00 // Value representing OFF

sbit SDATA= P1^0; // Define the individual bit;
sbit SCLK= P1^1; // Define the individual bit

char readchar_EE(char location);
void writechar_EE(char location,char val);
void i2c_write (unsigned char output_data);
char i2c_read (void);
void i2c_start (void);
void i2c_stop (void);
void i2c_ack (void);
void DelayMs(unsigned int number);

char readchar_EE(char location)
{ unsigned char data_in;

i2c_start(); // Send I2C Start Transfer i2c_write(0xA0); // Send identifier I2C address - Write i2c_write(location); // SEND START LOCATION in RTC (last 2 bits is the channel) i2c_stop(); // Send I2C Stop Transfer

i2c_start(); // Send I2C Start Transfer i2c_write(0xA1); // Send identifier I2C address - Read data_in = i2c_read(); i2c_stop(); return data_in;

}

void writechar_EE(char location,char val)
{

i2c_start(); // Send I2C Start Transfer i2c_write(0xA0); // Send identifier I2C address - Write i2c_write(location); // SEND START LOCATION in RTC (last 2 bits is the channel) i2c_write(val); // SEND START LOCATION in RTC (last 2 bits is the channel) i2c_stop();

}

void i2c_write (unsigned char output_data)
{ unsigned char index;

for(index = 0; index < 8; index++) // Send 8 bits to the I2C Bus { // Output the data bit to the I2C Bus SDATA = ((output_data & 0x80) ? 1 : 0); output_data <<= 1; // Shift the byte by one bit SCLK = HIGH; // Clock the data into the I2C Bus SCLK = LOW; }

index = SDATA; // Put data pin into read mode SCLK = HIGH; // Clock the ACK from the I2C Bus SCLK = LOW; SDATA=HIGH;
}

char i2c_read (void) { char index, input_data;

index = SDATA; // Put data pin into read mode

input_data = 0x00; for(index = 0; index < 8; index++) // Send 8 bits to the I2C Bus { input_data <<= 1; // Shift the byte by one bit SCLK = HIGH; // Clock the data into the I2C Bus input_data |= SDATA; // Input the data from the I2C Bus SCLK = LOW; } return input_data; }

void i2c_start (void)
{

SDATA = HIGH; // Set data line high SCLK = HIGH; // Set clock line high SDATA = LOW; // Set data line low (START SIGNAL) SCLK = LOW; // Set clock line low
}

void i2c_stop (void)
{ unsigned char input_var;

SCLK = LOW; // Set clock line low SDATA = LOW; // Set data line low SCLK = HIGH; // Set clock line high SDATA = HIGH; // Set data line high (STOP SIGNAL) input_var = SDATA; // Put port pin into HiZ
}

void i2c_ack (void)
{ char in_var; SDATA=LOW; SCLK = HIGH; // Clock the ACK from the I2C Bus SCLK = LOW; SDATA = HIGH; // Set data line high (STOP SIGNAL) in_var = SDATA; // Put port pin into HiZ
}

void DelayMs(unsigned int number)
{ unsigned char temp;
for(;number!=0;number--)
{ for(temp=112;temp!=0;temp--) ;
} }
void main()
{ unsigned char inputvalue,readvalue=0x00; inputvalue='A';

TMOD=0X20; //timer 1 auto reload TH1=0XFD; //9600 baud rate SCON=0X50; TR1=1;

writechar_EE(0x02,inputvalue); DelayMs(10); readvalue=readchar_EE(0x02);

SBUF=readvalue; while(TI==0); TI=0;

SBUF='B'; while(TI==0); TI=0;

while(1);
}