External eeprom Interfacing using I2C..showing Data in LCD

[thunaivendan]

Hi guys Have a problem on my code..data is not trasmitting in external eeprom and in LCD..I attach my code for I2C and LCD..kindly..check it reply for me guys

 

[babar_ali]

Hi,

Ist the hardware: SDA and SCL lines are not pulled up. See the files attached for I2C and LCD (4-bit). When you are writting to an EEPROM care must be taken during the write procedure. The EEPROM takes about 5ms of write time if i remember correctly. Also try to write in the in the following fashion.

void EEPROM_Write(char Data, unsigned char Address)
{
	I2C_Start();
	I2C_Write(SlavewriteAddress);
	I2C_Write(Address);					// Address to write data
	I2C_Write(Data);
	I2C_Stop();
        TDelayms(5);
}
char EEPROM_Read(unsigned char Address)
{
	I2C_Start();
	I2C_Write(SlavewriteAddress);
	I2C_Write(Address);						// Address to write data
	I2C_Restart();
	I2C_Write(SlaveReadAddress);
	EEPROMREAD = I2C_Read();
	I2C_ACK(0);								// NACK
	I2C_Stop();
}

Enjoy

 

[g_shyam1682]

Hello friend,

I have seen your whole code, i think you have one mistake in i2c_address function of your code

My suggestion is:

Change this line of code

l_address=address<<1; Here, address = 0xA0, after code execute, l_address = 0x40
l_address+=mode; Here, l_address = 0x41 or 0x40 according to mode.

With

l_address = address | mode; Here, l_address = 0xA1 or 0xA0 according to mode.


Hope this is help you,

Regards,
Ghanshyam

 

[thunaivendan]

Hello friend,

I have seen your whole code, i think you have one mistake in i2c_address function of your code

My suggestion is:

Change this line of code

l_address=address<<1; Here, address = 0xA0, after code execute, l_address = 0x40
l_address+=mode; Here, l_address = 0x41 or 0x40 according to mode.

With

l_address = address | mode; Here, l_address = 0xA1 or 0xA0 according to mode.


Hope this is help you,

Regards,
Ghanshyam

Thank u guy...just knnow found the simulation mistake..how to transfer string same the i2c_write function guys

- - - Updated - - -

thank u for best approach surely check it reply soon.....guys

- - - Updated - - -

Sir tell me logic and operation of 4-bit mode lcd in ur attached CODE..MsB send first and LSB...

 

[g_shyam1682]

Hi,

For external eeprom interfacing using i2c, i suggest you, please read complete datasheet of AT24C04 IC as reference. This datasheet contain detail read/write process for EEPROM and you can find some sample code for AT24c04 read/write in ASM language which can be converted in C which is exactly match to your EEPROM.

Please use complete English in post write, I don't understand your shorts.

Regards,

 

[thunaivendan]

Sure..i will correct it...
Eventhough i changed logic in address function...data is not shown guy..and i doubt in disp_data() ,i2c_read() function please verify it

void i2c_address(unsigned char,unsigned char);
void disp_data(unsigned char *);
unsigned char i2c_read(unsigned char);
void main()
{
TRISE=0;
PORTE=0;
TRISD=0;
PORTD=0;
TRISC=0xff;
PORTC=0;
ADCON1=0x06;
lcd_init();
i2c_init();
i2c_start();
i2c_address(0xa0,0);
// i2c_ack();
i2c_restart();
i2c_address(0xa0,0);
//i2c_ack();
//i2c_address(0x00,0);
// i2c_ack();
i2c_write(0x05);
//i2c_ack();
i2c_stop();
i2c_ack();
// i2c_wait();
i2c_start();
i2c_address(0xa1,1);
i2c_restart();
i2c_address(0xa1,1);
i2c_read(0);

*value=i2c_read(0);
disp_data((value));
//delay_ms(10);
}


void i2c_address(unsigned char address, unsigned char mode)
{
unsigned char l_address;
l_address=address|mode;
//l_address+=mode;
i2c_wait();
SSPBUF = l_address;
}
unsigned char i2c_read(unsigned char ack)
{
// Read data from slave
// ack should be 1 if there is going to be more data read
// ack should be 0 if this is the last byte of data read
unsigned char i2c_read_data;

i2c_wait();
RCEN=1;
while(RCEN);
while(!BF);
i2c_wait();
if ( ack ) ACKDT=0; // Ack
else ACKDT=1; // NAck
ACKEN=1; // send acknowledge sequence
// i2c_read_data = SSPBUF;
//i2c_wait();
return(SSPBUF);
}
Above function are doubt..and also how to pass data as argument in write function

these are above function doubted..

 

[g_shyam1682]

Hi,

In your code, you write 0x05 value at Memory location 0x00, as you pass 0x00 address. but i doubt in reading process, you don't pass 0x00 address from which data read.
I again suggest you, please read complete and carefully datasheet of AT24C04. it has all need sequence for write and read process.

Regards,