save data in pic

[mister_e]

I can't believe it's impossible.. just post your code here first!

[ErnieM]

and how can i give signal for write data to eeprom before power supply off.

Well... keep a copy of the data in a register, and compare your new value in the loop to the existing register value.

When and only when you have a new value, send the new value to the EEPROM, and update your register value too. Don't do it too often, as there is a limited number of cycles on that memory.