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Program to write and read a byte between P89V51RD2 and ST M24C64

Hello All,

I am finding it really hard to perform write and read operations on the EEPROM connected to the MCU by two wires using the I2C Protocol.

I've read the data sheets, written the code exactly matching the datasheet info, but it was of no avail.

Please help me out.

My code looks something like this

void Write_Start(void)
        {
                E2P_SDA = 1;
                E2P_SCL = 1;
                delay_i2c();
                E2P_SDA = 0;
                delay_i2c();
                E2P_SCL = 0;
                delay_i2c();
        }

void Write_to_E2P(void)
        {
                unsigned char DEV_SEL_CODE = 0x0A0;
                unsigned char ADDR_MSB = 0x50;
                unsigned char ADDR_LSB = 0x05;
                unsigned char i;

                Write_Start();

                for(i=7;i>=0;i--)
                        {
                                E2P_SDA = DEV_SEL_CODE^i;
                                E2P_SCL = 0;
                                delay_i2c();
                                E2P_SCL = 1;
                                delay_i2c();
                        }

                E2P_SDA = 1;
                E2P_SCL = 0;
                delay_i2c();
                E2P_SCL = 1;
                delay_i2c();
                delay_i2c();
                E2P_SCL = 0;
                delay_i2c();

                if(E2P_SDA == 0)
                        LED1=1;

                for(i=7;i>=0;i--)
                        {
                                E2P_SDA = ADDR_MSB^i;
                                E2P_SCL = 0;
                                delay_i2c();
                                E2P_SCL = 1;
                                delay_i2c();
                        }

                E2P_SDA = 1;
                E2P_SCL = 0;
                delay_i2c();
                E2P_SCL = 1;
                delay_i2c();
                delay_i2c();
                E2P_SCL = 0;
                delay_i2c();

                if(E2P_SDA == 0)
                        LED2=1;

                for(i=7;i>=0;i--)
                        {
                                E2P_SDA = ADDR_LSB^i;
                                E2P_SCL = 0;
                                delay_i2c();
                                E2P_SCL = 1;
                                delay_i2c();
                        }

                E2P_SDA = 1;
                E2P_SCL = 0;
                delay_i2c();
                E2P_SCL = 1;
                delay_i2c();
                delay_i2c();
                E2P_SCL = 0;
                delay_i2c();

                if(E2P_SDA == 0)
                        LED3=1;

                for(i=7;i>=0;i--)
                        {
                                E2P_SDA = current_channel^i;
                                E2P_SCL = 0;
                                delay_i2c();
                                E2P_SCL = 1;
                                delay_i2c();
                        }

                E2P_SDA = 1;
                E2P_SCL = 0;
                delay_i2c();
                E2P_SCL = 1;
                delay_i2c();
                delay_i2c();
                E2P_SCL = 0;
                delay_i2c();

                if(E2P_SDA == 0)
                        LED4=1;


        }