15.1.2.5 Modifying Flash Program Memory
When modifying existing data in a program memory, data within the memory row
            must be read and saved in a RAM image. Program memory is modified using the following
            steps: 
    - Load the starting address of the row to be modified.
 - Read the existing data from the row into a RAM image.
 - Modify the RAM image to contain the new data to be written into program memory.
 - Load the starting address of the row to be rewritten.
 - Erase the program memory row.
 - Load the write latches with data from the RAM image.
 - Initiate a programming operation.
 
Note: 
                    
            - See Figure 15-1.
 - See Figure 15-3.
 - See Figure 15-5.
 
