UPD78F0411GA-GAM-AX Datasheet, PDF (524/564 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

CHAPTER 24 FLASH MEMORY
24.8 Flash Memory Programming by Self-Programming (Under Development)
The 78K0/LC3 supports a self-programming function that can be used to rewrite the flash memory via a user
program. Because this function allows a user application to rewrite the flash memory by using the 78K0/LC3 self-
programming sample library, it can be used to upgrade the program in the field.
If an interrupt occurs during self-programming, self-programming can be temporarily stopped and interrupt
servicing can be executed. To execute interrupt servicing, restore the normal operation mode after self-programming
has been stopped, and execute the EI instruction. After the self-programming mode is later restored, self-
programming can be resumed.
Cautions 1. The self-programming function cannot be used when the CPU operates with the subsystem
clock.
2. Input a high level to the FLMD0 pin during self-programming.
3. Be sure to execute the DI instruction before starting self-programming.
The self-programming function checks the interrupt request flags (IF0L, IF0H, IF1L, and IF1H).
If an interrupt request is generated, self-programming is stopped.
4. Self-programming is also stopped by an interrupt request that is not masked even in the DI
status. To prevent this, mask the interrupt by using the interrupt mask flag registers (MK0L,
MK0H, MK1L, and MK1H).
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User’s Manual U18698EJ1V0UD