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:
- 1.Load the starting address of the
row to be modified.
- 2.Read the existing data from the
row into a RAM image.
- 3.Modify the RAM image to contain
the new data to be written into program memory.
- 4.Load the starting address of the
row to be rewritten.
- 5.Erase the program memory row.
- 6.Load the write latches with data
from the RAM image.
- 7.Initiate a programming
operation.
Figure 1. Program Flash Memory Modify Sequence