SH7052 Datasheet, PDF (784/919 Pages) Renesas Technology Corp – SuperHTM RISC engine

21.6.2 User Program Mode
After setting FWE, the user should branch to, and execute, the previously prepared
programming/erase control program.
The Flash memory cannot be read while the flash memory is being written/erased. Execute the
control program for programming or erasing using the on-chip RAM, external memory, or flash
memory outside the address areas.
Use the following procedure (figure 21.12) to execute the programming control program that
writes to flash memory (when transferred to RAM).
Write FWE assessment program
1
and transfer program
FWE = 1
2
(user program mode)
3
Transfer programming/erase
control program to RAM
Execute programming/
4 ^{erase control program in RAM}
(flash memory rewriting)
Execute user application
5
program
Figure 21.12 User Program Mode Execution Procedure
Note: When programming and erasing, start the watchdog timer so that measures can be taken to
prevent program runaway, etc. Memory cells may not operate normally if
overprogrammed or overerased due to program runaway.
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