Writing a single byte or an array in EEPROM

Question: Can we write EEPROM one byte once?

 

Answer:

EEPROM architecture doesn’t allow partial writes. It only supports writing into an entire row (16 bytes). Hence in order to modify only one byte or an array, follow the steps given below-

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       Find the address of the concerned byte (starting address in case of an array).

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       Calculate the row in which the byte or array is located.

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        Read back the entire row (Read back can be done in same way as reading SRAM).

  •  

        Modify only the required locations.

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        Program the entire row with only the concerned locations modified (using EEPROM API’s).

 

Note: in case of an array of size more than 16 bytes or if the array spans over two rows, the steps mentioned above should be repeated for the remaining rows also.