How to write data in Flash data memory?

"So, please send me some guidelines for writing the data in Flash."

Surely, those guidelines are given in the Application Note?!
Re-Check what you've done against the application note, and the Datasheet.

Nobody else can do that for you without seeing your code, can they?!

Dear Sir,

I had read the datasheet and according to that only i wrote one simple program to store the bytes in one page.Here I am sending the function statements to write the bytes in data memory.

void Flash_Mem_Write_Page(void)
{ EADRH=0x00; //Select Address hoiher byte
EADRL=0x01; //Select addres lower byte

EDATA1=0x12; //writing the data
EDATA2=0x13;
EDATA3=0x14;
EDATA4=0x15;

ECON=0x02; //writing the bytes
Sleep(40);
ECON=0x04; //verifying
Sleep(22);

if(!ECON) //match is there it will return 0in ECON
printf("WRITE\n");
else
printf("NOT WRITE\n");
}

Thank you very much for replying.

"I had read the datasheet"

I hope you read it more carefully than the instructions here for posting source code:

www.danlhenry.com/.../keil_code.png

You also, apparently, didn't notice the problem in the 'Preview' - I hope you've reviewed your own code more carefully?

First, you said, "I wrote the routines as mentioned in application note"

Now you say, "I had read the datasheet and according to that only i wrote one simple program" (my emphasis)

So which is it - datasheet or application note?

or both?

or what?

Well, if you wrote the code according to the datasheet, did you also see the note that the bytes in the flash must be erased before new data can be written to them ?

Also, what is the point of the calls to sleep() ?

Seems like the calls to sleep are to allow time for the flash programming operation to occur. Erases are very slow; writes are not that bad, but still slow.

I haven't checked the data sheet, but most flash parts have a way to check to see if an operation is complete, rather than just waiting the worst-case time. I'm usually a little more comfortable with that sort of handshake than a hard-coded delay. But sleeping for longer than the worst-case time spec'd in the datasheet should work.

Seems like the calls to sleep are to allow time for the flash programming operation to occur.

It seems like that to me too, but I was asking for an answer from the OP - if he wrote his code according to the datasheet, then he should have noticed that it is not necessary to manually wait for anything when writing to the flash - the CPU will idle automatically until the write operation finishes. When the next instruction after the write command executes, the write operation is already over.

(Yes, this means that the chip may well spend several milliseconds doing nothing, including not responding to interrupts)

Look at followed example. It works on ADuC847.

// ****************************************************
// save 4 bytes to addr 0x3FF
// ****************************************************
void SaveSetPointToFlash(unsigned char* puc)
{
 EA = 0;          // Disable interrupts before saving
 EADRH = 0x03;    // High byte of page Address
 EADRL = 0xFF;     // Low byte of page Address
 EDATA1 = puc[0]; // Data to flash
 EDATA2 = puc[1]; // Data to flash
 EDATA3 = puc[2]; // Data to flash
 EDATA4 = puc[3]; // Data to flash
 ECON = 0x05;     // Erase Page
 ECON = 0x02;     // Write Page
 ECON = 0x04;     // Verify Page
 EA = 1;          // enable interrupts after saving
}

As notes Christoph you should provide erasing page and remove delays.

chip may well spend several milliseconds doing nothing, including not responding to interrupts

Yes, we should not think about flash like about operational memory. It is hard drive on chip and as hard drive it is slow.